Cell Membranes Chapt 5. The Cell Membrane. Cell Membrane: At Very High Magnification & in color

Size: px
Start display at page:

Download "Cell Membranes Chapt 5. The Cell Membrane. Cell Membrane: At Very High Magnification & in color"

Transcription

1 Cell Membranes Chapt 5 The Cell Membrane Cell Membrane: At Very High Magnification & in color 1

2 Membrane Structure Cell Membrane Every cell is encircled by a membrane and most cells contain an extensive intracellular membrane system. Membranes fence off the cell's interior from its surroundings. Membranes let in water, certain ions and substrates and they excrete waste substances. They act to protect the cell. Without a membrane the cell contents would diffuse into the surroundings, information containing molecules would be lost and many metabolic pathways would cease to work: The cell would die! Cell Membranes: Surround all cells Fluid-like composition like soap bubbles Composed of: Lipids in a bilayer Proteins embedded in lipid layer (called transmembrane proteins) And, Proteins floating within the lipid sea (called integral proteins) And Proteins associated outside the lipid bilayer (peripheral). 2

3 Membrane Lipids Composed largely of phospholipids Phospholipids composed of.glycerol and two fatty acids + PO 4 group P-Lipids are polar molecules P-Lipids are represented like this Text pg. 81 Membrane Lipids form a Bilayer Outside layer Inside Layer Quiz If Phospholipids are polar, which end seeks out water and which avoids water? 3

4 Phospholipid Molecule Model phosphate (hydrophilic) glycerol fatty acids (hydrophobic) Membrane Proteins Integral: embedded within bilayer Peripheral: reside outside hydrophobic region of lipids Text pg. 80 Membrane Proteins Text pg 80 4

5 Integral membrane proteins Peripheral membrane proteins Integral Membrane Models Fluid Mosaic Model - lipids arranged in bilayer with proteins embedded or associated with the lipids. 5

6 Fluid Mosaic Membrane Text pg 80 Evidence for the Fluid Mosaic Model (Cell Fusion) More Evidence for the Fluid Mosaic Model 6

7 Membrane Functions allows for different conditions between inside and outside of cell subdivides cell into compartments with different internal conditions allows release of substances from cell via vesicle fusion with outer membrane: Membrane Permeability Biological membranes are physical barriers..but which allow small uncharged molecules to pass And, lipid soluble molecules pass through Big molecules and charged ones do NOT pass through How to get other molecules across membranes?? There are two ways that the molecules typically move through the membrane: passive transport and active transport Active transport requires that the cell use energy that it has obtained from food to move the molecules (or larger particles) through the cell membrane. Passive transport does not require such an energy expenditure, and occurs spontaneously. 7

8 Membrane Transport Mechanisms I. Passive Transport Diffusion- simple movement from regions of high concentration to low concentration Osmosis - diffusion of water across a semipermeable membrane Facilitated diffusion- protein transporters which assist in diffusion Text pg 89 Membrane Transport Mechanisms II. Active Transport Active transport- proteins which transport against concentration gradient. Requires energy input Text pg 89 Diffusion Movement generated by random motion of particles. Caused by internal thermal energy. Movement always from region of high free energy(high concentration) to regions of low free energy (low conc.) Text pg 86 8

9 Movement of water across a semi-permeable barrier. Osmosis Example: Salt in water, cell membrane is barrier. Salt will NOT move across membrane, water will. Text pg 87 Osmosis in Hypertonic medium cell Hypertonic solutions- shrink cells 9

10 Osmosis in Hypotonic medium Hypotonic solutions- swell cells Endocytosis Transports macromolecules and large particles into the cell. Part of the membrane engulfs the particle and folds inward to bud off. Fig

11 Endocytosis Putting Out the Garbage Vesicles (lysosomes, other secretory vesicles) can fuse with the membrane and open up the the outside Exocytosis (Cellular Secretion) 11

12 Movies! Membrane Permeability 1) lipid soluble solutes go through faster 1) smaller molecules go faster 1) uncharged & weakly charged go faster 2) Channels or pores may also exist in membrane to allow transport 1 2 Cellular Membranes REVIEW Importance of Membranes Membrane Structure Proteins Fluid Mosaic model Permeability Types of Transport Passive and Active 12

13 Types of Protein Transporters: Ion Channels work by facilitated diffusion No E! deal with small molecules... ions open pores are gated - Can change shape. How? How much gets in? important in cell communication Ion Channels Work fast: No conform. changes needed Not simple pores in membrane: specific to different ions (Na, K, Ca...) gates control opening Toxins, drugs may affect channels saxitoxin, tetrodotoxin cystic fibrosis Toxins how they work 13

14 Cystic Fibrosis Fatal genetic disorder Mucus build-up results in lung and liver failure Patients die between 4 and 30 yrs. Single gene defect 1 in 25 Caucasians carry 1 bad gene copy 1 in 2500 kids has it in Canada Testing CF Cont ~Proteins for diffusion of salt into the airways don't work. ~Less salt in the airways means less water in the airways. ~ Less water in the airways means mucus layer is very sticky (viscous). ~Sticky mucus cannot be easily moved to clear particles from the lungs. ~Sticky mucus traps bacteria and causes more lung infections. Transport Proteins Facilitated Diffusion & Active Transport move solutes faster across membrane highly specific to specific solutes can be inhibited by drugs 14

15 Types of Protein Transporters A. Facilitated Diffusion Assist in diffusion process. Solutes go from High conc to Low conc. Examples: Glucose transporters Text pg 88 Facilitated Diffusion The Glucose Transporters Transport of glucose into cells mediated by proteins in the GLUT (GLUcose Transport) family of transporters. There are 7 different, but related, proteins. But, only four (GLUT1-4) are known to be involved in glucose transport. All GLUT proteins share a set of similar structural features and are all about 500 amino acids in length (giving them a predicted molecular weight of about 55,000 Daltons) Glucose uptake shows saturation and glucose uptake can be inhibited by drugs A classic Membrane Transport protein Glucose Transporter Characteristics: integral protein: spans the membrane 12 alpha helices woven into membrane 55,000 mol. wt. Text pg

16 Glucose Transporter: How it works.. glucose binds to outside of transporter (exterior side with higher glucose conc.) glucose binding causes a conform. change in protein glucose drops off inside cell protein reassumes 1st configuration Types of Protein Transporters: Active Transport carrier proteins go against the concentration gradients Low to High require Energy to function (ATP, PEP, light energy, electron transport) Membrane Transport: Active transport Movement from region of low free energy(low concentration) to regions of high free energy (high conc.) Requires energy input 16

17 Active Transport: Sodium-Potassium Pump Na+ high Na+ low K+ low K+ high Balance of the two ions goes hand-in-hand ATP required for maintenance of the pump The sodium/potassium pump All nerve and muscle cells have a high internal potassium ion concentration and a low internal sodium ion concentration. [Ki=166 mm; Ko=5 mm; Nai=18 mm; Nao=135 mm]. Early on, it was thought that the nerve and muscle membranes were relatively impermeable to these ions and that the difference in ionic concentration was set up in early development of the cells. The membrane then became impermeable. The later availability and use of radioactive Na and K ions showed that this was not true and that there was a metabolic pump that pumped Na out of the cell and K in; the ratio being 3 Na pumped out of the cell for every 2 K pumped into the cell. Is a Protein Involved? Experiments showed a dependency of both Na and K ions for pump to work Pump was inhibited by ouabain (a drug) 1957: an ATPaseenzyme was found to be associated with Na/K pumping Studies showed this ATPase capable of pumping Na/K ions Text pg 90 17

18 Sodium/Potassium ATPase Protein Made of 2 large and 2 small subunits 2 large units span membrane inside region: contains ATP binding site inside: binding sites for Na outside: binding site for K How does it work?? Sodium-Potassium Pump Text pg. 90 Na-K Pump Model: Part I 3 Na+ bind to inner region of protein Na+ binding triggers phosphorylation of protein. ATP ADP + Pi Phosphorylation causes conformation change and Na+ binding site faces outside 3 Na+ released to outside 18

19 Na-K Active Pump: Part II 2 K+ ions on outside are able to bind K+ binding causes dephosphorylation and new conformation change 2K+ ions exposed to inside and released Cyclic process uses ATP energy to drive Na & K ion transport againstconc. Gradient Cell Junctions Allow specific types of cells to stay together to perform special jobs Layers of these types of cells Line body cavities Cover body surfaces 3 Types of Cell Junctions 1. Tight Junctions 2. Desmosomes 3. Gap Junctions 19

20 Seal tissues and prevent leaks Link epithelial cells together Prevent things from moving through the intercellular space Restrict migration of proteins and phospholipids Tight Junctions Like spot welds! Desmosomes Dense plaques with fibers attached- Anchor cells together from one side to the other. These cells withstand lots of abuse! Cell to cell communication. Gap Junctions Protein channels- (what type?) connexons Plasmodesmata 20

21 Put Them All Together Membrane Structure The cell is highly organized with many functional units or organelles inside. Most of these units are limited by one or more membranes. To perform the functions of an organelle, the membrane is specialized in that it contains speci fic proteins and lipid components that enable it to perform its unique roles. In essence membranes are essential for the integrity and function of the cell. Membrane functions: be protective regulate transport in and out of cell or organelle allow selective receptivity and signal transduction by providing transmembrane receptors that bind signaling molecules allow cell recognition provide anchoring sites for cytoskeletal components. This allows the cell to maintain its shape and perhaps move to distant sites. provide a stable site for the binding and catalysis of enzymes. regulate the fusion of the membrane with other membranes in the cell via specialized junctions provide a passageway across the membrane for certain molecules allow directed cell or organelle motility 21

The structure and function of the plasma membrane

The structure and function of the plasma membrane The structure and function of the plasma membrane Our current view of membrane structure is based on the fluid mosaic model. This model proposes that membranes are not rigid, with molecules locked into

More information

1. The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called.

1. The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called. Cell Membranes 1. The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called. 2. Due to the repellent nature of the polar water molecules, the tails of the phospholipids

More information

Transport Across Cell Membranes

Transport Across Cell Membranes Transport Across Cell Membranes CELL MEMBRANE STRUCTURE A phospholipid bilayer makes up the main part of the cell membrane Each phospholipid molecule contains a charged polar head (H 2 O-loving) and non-polar,

More information

Membrane Structure and Function

Membrane Structure and Function Membrane Structure and Function -plasma membrane acts as a barrier between cells and the surrounding. -plasma membrane is selective permeable -consist of lipids, proteins and carbohydrates -major lipids

More information

Chapter 8. Movement across the Cell Membrane. AP Biology

Chapter 8. Movement across the Cell Membrane. AP Biology Chapter 8. Movement across the Cell Membrane More than just a barrier Expanding our view of cell membrane beyond just a phospholipid bilayer barrier phospholipids plus Fluid Mosaic Model In 1972, S.J.

More information

4. Biology of the Cell

4. Biology of the Cell 4. Biology of the Cell Our primary focus in this chapter will be the plasma membrane and movement of materials across the plasma membrane. You should already be familiar with the basic structures and roles

More information

CELL MEMBRANES, TRANSPORT, and COMMUNICATION. Teacher Packet

CELL MEMBRANES, TRANSPORT, and COMMUNICATION. Teacher Packet AP * BIOLOGY CELL MEMBRANES, TRANSPORT, and COMMUNICATION Teacher Packet AP* is a trademark of the College Entrance Examination Board. The College Entrance Examination Board was not involved in the production

More information

CHAPTER 5.1 5.2: Plasma Membrane Structure

CHAPTER 5.1 5.2: Plasma Membrane Structure CHAPTER 5.1 5.2: Plasma Membrane Structure 1. Describe the structure of a phospholipid molecule. Be sure to describe their behavior in relationship to water. 2. What happens when a collection of phospholipids

More information

Six major functions of membrane proteins: Transport Enzymatic activity

Six major functions of membrane proteins: Transport Enzymatic activity CH 7 Membranes Cellular Membranes Phospholipids are the most abundant lipid in the plasma membrane. Phospholipids are amphipathic molecules, containing hydrophobic and hydrophilic regions. The fluid mosaic

More information

1.1.2. thebiotutor. AS Biology OCR. Unit F211: Cells, Exchange & Transport. Module 1.2 Cell Membranes. Notes & Questions.

1.1.2. thebiotutor. AS Biology OCR. Unit F211: Cells, Exchange & Transport. Module 1.2 Cell Membranes. Notes & Questions. thebiotutor AS Biology OCR Unit F211: Cells, Exchange & Transport Module 1.2 Cell Membranes Notes & Questions Andy Todd 1 Outline the roles of membranes within cells and at the surface of cells. The main

More information

Cell Membrane Structure and Function. Prof. Dr. Turgut Ulutin

Cell Membrane Structure and Function. Prof. Dr. Turgut Ulutin Cell Membrane Structure and Function Prof. Dr. Turgut Ulutin Why do we need the plasma membrane? Keeping the goods concentrated Keeping harmful materials out Transports substances in and out of the cell

More information

Modes of Membrane Transport

Modes of Membrane Transport Modes of Membrane Transport Transmembrane Transport movement of small substances through a cellular membrane (plasma, ER, mitochondrial..) ions, fatty acids, H 2 O, monosaccharides, steroids, amino acids

More information

AP Biology. The Cell Membrane

AP Biology. The Cell Membrane The Cell Membrane Phospholipids Phosphate head hydrophilic Fatty acid tails hydrophobic Arranged as a bilayer Phosphate attracted to water Fatty acid repelled by water Aaaah, one of those structure function

More information

Transmembrane proteins span the bilayer. α-helix transmembrane domain. Multiple transmembrane helices in one polypeptide

Transmembrane proteins span the bilayer. α-helix transmembrane domain. Multiple transmembrane helices in one polypeptide Transmembrane proteins span the bilayer α-helix transmembrane domain Hydrophobic R groups of a.a. interact with fatty acid chains Multiple transmembrane helices in one polypeptide Polar a.a. Hydrophilic

More information

BSC 2010 - Exam I Lectures and Text Pages. The Plasma Membrane Structure and Function. Phospholipids. I. Intro to Biology (2-29) II.

BSC 2010 - Exam I Lectures and Text Pages. The Plasma Membrane Structure and Function. Phospholipids. I. Intro to Biology (2-29) II. BSC 2010 - Exam I Lectures and Text Pages I. Intro to Biology (2-29) II. Chemistry of Life Chemistry review (30-46) Water (47-57) Carbon (58-67) Macromolecules (68-91) III. Cells and Membranes Cell structure

More information

FIGURE 2.18. A. The phosphate end of the molecule is polar (charged) and hydrophilic (attracted to water).

FIGURE 2.18. A. The phosphate end of the molecule is polar (charged) and hydrophilic (attracted to water). PLASMA MEMBRANE 1. The plasma membrane is the outermost part of a cell. 2. The main component of the plasma membrane is phospholipids. FIGURE 2.18 A. The phosphate end of the molecule is polar (charged)

More information

Ch. 8 - The Cell Membrane

Ch. 8 - The Cell Membrane Ch. 8 - The Cell Membrane 2007-2008 Phospholipids Phosphate head hydrophilic Fatty acid tails hydrophobic Arranged as a bilayer Phosphate attracted to water Fatty acid repelled by water Aaaah, one of those

More information

Cell Membrane Structure (and How to Get Through One)

Cell Membrane Structure (and How to Get Through One) Cell Membrane Structure (and How to Get Through One) A cell s membrane is a wall of sorts that defines the boundaries of a cell. The membrane provides protection and structure for the cell and acts as

More information

BIOLOGICAL MEMBRANES: FUNCTIONS, STRUCTURES & TRANSPORT

BIOLOGICAL MEMBRANES: FUNCTIONS, STRUCTURES & TRANSPORT BIOLOGICAL MEMBRANES: FUNCTIONS, STRUCTURES & TRANSPORT UNIVERSITY OF PNG SCHOOL OF MEDICINE AND HEALTH SCIENCES DISCIPLINE OF BIOCHEMISTRY AND MOLECULAR BIOLOGY BMLS II / B Pharm II / BDS II VJ Temple

More information

Biological cell membranes

Biological cell membranes Unit 14: Cell biology. 14 2 Biological cell membranes The cell surface membrane surrounds the cell and acts as a barrier between the cell s contents and the environment. The cell membrane has multiple

More information

Division Ave High School AP Biology

Division Ave High School AP Biology The Cell Membrane https://youtu.be/y31dlj6ugge Journal Diagrams Shark book pg. 82 Wolves book pg. 88-89 Membrane Proteins Copy table Cell Membrane Proteins Fluid Mosaic Model Cell Membrane Phospholipids

More information

Unit 2: Cells, Membranes and Signaling CELL MEMBRANE. Chapter 5 Hillis Textbook

Unit 2: Cells, Membranes and Signaling CELL MEMBRANE. Chapter 5 Hillis Textbook Unit 2: Cells, Membranes and Signaling CELL MEMBRANE Chapter 5 Hillis Textbook HOW DOES THE LAB RELATE TO THE NEXT CHAPTER? SURFACE AREA: the entire outer covering of a cell that enables materials pass.

More information

Cells Need to Exchange Materials with the Extracellular Fluid. Membrane Transport. Plasma Membrane. Cells Must Control Movements of Materials

Cells Need to Exchange Materials with the Extracellular Fluid. Membrane Transport. Plasma Membrane. Cells Must Control Movements of Materials Membrane Transport Chapter 6 Cells Need to Exchange Materials with the Extracellular Fluid Take in nutrients O 2 energy substrates building materials cofactors Dispose of wastes CO 2 Urea Cells Must Control

More information

IB104 - Lecture 9 - Membranes

IB104 - Lecture 9 - Membranes There have been many magnificent boats built to try to reach 50 knots. This was the creation of an Australian team that held the record for more than a decade, from 1993 till 2005, at 46.5 knots with their

More information

What will you learn?

What will you learn? What will you learn? Cell Membrane and Transport PLO B9 B10 It is expected that students will analyse the structure and function of the cell membrane explain why cells divide when they reach a particular

More information

The light comes from a set of chemical reactions, the luciferin-luciferase system Fireflies make light energy from chemical energy

The light comes from a set of chemical reactions, the luciferin-luciferase system Fireflies make light energy from chemical energy Cool Fires Attract Mates and Meals Fireflies use light instead of chemical signals to send a message to potential mates Females can also use light to attract males of other firefly species, as meals not

More information

The human respiratory system includes the nose, the larynx, and the lungs. This body system helps maintain homeostasis by

The human respiratory system includes the nose, the larynx, and the lungs. This body system helps maintain homeostasis by Study Island 1. During heatstroke, the body can't dispose of excess heat. As a result, the homeostatic balance is disturbed, and internal body temperatures can reach as much as 110. Heatstroke is dangerous

More information

Cell Biology - Part 2 Membranes

Cell Biology - Part 2 Membranes Cell Biology - Part 2 Membranes The organization of cells is made possible by membranes. Membranes isolate, partition, and compartmentalize cells. 1 Membranes isolate the inside of the cell from the outside

More information

Mammalian Physiology. Cellular Membranes Membrane Transport UNLV. PHYSIOLOGY, Chapter 1 Berne, Levy, Koeppen, Stanton UNIVERSITY OF NEVADA LAS VEGAS

Mammalian Physiology. Cellular Membranes Membrane Transport UNLV. PHYSIOLOGY, Chapter 1 Berne, Levy, Koeppen, Stanton UNIVERSITY OF NEVADA LAS VEGAS Mammalian Physiology Cellular Membranes Membrane Transport UNLV 1 UNIVERSITY OF NEVADA LAS VEGAS PHYSIOLOGY, Chapter 1 Berne, Levy, Koeppen, Stanton Objectives Describe the structure of the cell membrane

More information

Osmosis, Diffusion and Cell Transport

Osmosis, Diffusion and Cell Transport Osmosis, Diffusion and Cell Transport Types of Transport There are 3 types of transport in cells: 1. Passive Transport: does not use the cell s energy in bringing materials in & out of the cell 2. Active

More information

Cell Membrane & Tonicity Worksheet

Cell Membrane & Tonicity Worksheet NAME ANSWER KEY DATE PERIOD Cell Membrane & Tonicity Worksheet Composition of the Cell Membrane & Functions The cell membrane is also called the PLASMA membrane and is made of a phospholipid BI-LAYER.

More information

Cell Membrane Coloring Worksheet

Cell Membrane Coloring Worksheet Cell Membrane Coloring Worksheet Composition of the Cell Membrane & Functions The cell membrane is also called the plasma membrane and is made of a phospholipid bilayer. The phospholipids have a hydrophilic

More information

Chapter 5: The Working Cell

Chapter 5: The Working Cell Chapter 5: The Working Cell SOME BASIC ENERGY CONCEPTS Energy makes the world go around, but what is energy? Energy is defined as the capacity to perform work. Kinetic energy is the energy of motion. Potential

More information

7. A selectively permeable membrane only allows certain molecules to pass through.

7. A selectively permeable membrane only allows certain molecules to pass through. CHAPTER 2 GETTING IN & OUT OF CELLS PASSIVE TRANSPORT Cell membranes help organisms maintain homeostasis by controlling what substances may enter or leave cells. Some substances can cross the cell membrane

More information

The Lipid Bilayer Is a Two-Dimensional Fluid

The Lipid Bilayer Is a Two-Dimensional Fluid The Lipid Bilayer Is a Two-Dimensional Fluid The aqueous environment inside and outside a cell prevents membrane lipids from escaping from bilayer, but nothing stops these molecules from moving about and

More information

Chapter 5 The Plasma Membrane and Transport

Chapter 5 The Plasma Membrane and Transport Chapter 5 The Plasma Membrane and Transport State Standard Standard 1.a. Membrane Function 1, Forms a boundary between living cells and their surroundings. 2. Controls the movement of molecules into and

More information

BIOLOGY 12 - Cell Membrane and Cell Wall Function: Chapter Notes

BIOLOGY 12 - Cell Membrane and Cell Wall Function: Chapter Notes BIOLOGY 12 - Cell Membrane and Cell Wall Function: Chapter Notes The cell membrane is the gateway into the cell, and must allow needed things such as nutrients into the cell without letting them escape.

More information

Chapter 3. Cellular Structure and Function Worksheets. 39 www.ck12.org

Chapter 3. Cellular Structure and Function Worksheets. 39 www.ck12.org Chapter 3 Cellular Structure and Function Worksheets (Opening image copyright by Sebastian Kaulitzki, 2010. Used under license from Shutterstock.com.) Lesson 3.1: Introduction to Cells Lesson 3.2: Cell

More information

Section 7-3 Cell Boundaries

Section 7-3 Cell Boundaries Note: For the past several years, I ve been puzzling how to integrate new discoveries on the nature of water movement through cell membranes into Chapter 7. The Section below is a draft of my first efforts

More information

Cells and Their Housekeeping Functions Cell Membrane & Membrane Potential

Cells and Their Housekeeping Functions Cell Membrane & Membrane Potential Cells and Their Housekeeping Functions Cell Membrane & Membrane Potential Shu-Ping Lin, Ph.D. Institute of Biomedical Engineering E-mail: splin@dragon.nchu.edu.tw Website: http://web.nchu.edu.tw/pweb/users/splin/

More information

Anatomy and Physiology Placement Exam 2 Practice with Answers at End!

Anatomy and Physiology Placement Exam 2 Practice with Answers at End! Anatomy and Physiology Placement Exam 2 Practice with Answers at End! General Chemical Principles 1. bonds are characterized by the sharing of electrons between the participating atoms. a. hydrogen b.

More information

Ch 1 - The Cell & Cell Processes

Ch 1 - The Cell & Cell Processes Ch 1 - The Cell & Cell Processes P All cells have Cell membrane - phospholipid bilayer surrounding cell parts Cytoplasm - everything between cell membrane + nucleus P Most cells have Nucleus - brain of

More information

Membrane Structure and Function

Membrane Structure and Function Membrane Structure and Function Part A Multiple Choice 1. The fluid mosaic model describes membranes as having A. a set of protein channels separated by phospholipids. B. a bilayer of phospholipids in

More information

Date: Student Name: Teacher Name: Jared George. Score: 1) A cell with 1% solute concentration is placed in a beaker with a 5% solute concentration.

Date: Student Name: Teacher Name: Jared George. Score: 1) A cell with 1% solute concentration is placed in a beaker with a 5% solute concentration. Biology Keystone (PA Core) Quiz Homeostasis and Transport - (BIO.A.4.1.1 ) Plasma Membrane, (BIO.A.4.1.2 ) Transport Mechanisms, (BIO.A.4.1.3 ) Transport Facilitation Student Name: Teacher Name: Jared

More information

Keystone Review Practice Test Module A Cells and Cell Processes. 1. Which characteristic is shared by all prokaryotes and eukaryotes?

Keystone Review Practice Test Module A Cells and Cell Processes. 1. Which characteristic is shared by all prokaryotes and eukaryotes? Keystone Review Practice Test Module A Cells and Cell Processes 1. Which characteristic is shared by all prokaryotes and eukaryotes? a. Ability to store hereditary information b. Use of organelles to control

More information

Transporting molecules across cell membranes. Nutrients, wastes, hormones, ions

Transporting molecules across cell membranes. Nutrients, wastes, hormones, ions Transporting molecules across cell membranes Nutrients, wastes, hormones, ions Recall phospholipid bilayer It s a barrier! Only a small subset of molecules may pass through without help Cell membrane Sense

More information

PASSIVE TRANSPORT PROCESSES

PASSIVE TRANSPORT PROCESSES BIOZONE Assignment #2 Cell Membrane Transport PASSIVE TRANSPORT PROCESSES 1. Describe two properties of an exchange surface that would facilitate rapid diffusion rates*: (a) thin membrane (b) porous membrane

More information

Keystone Study Guide Module A: Cells and Cell Processes

Keystone Study Guide Module A: Cells and Cell Processes Keystone Study Guide Module A: Cells and Cell Processes Topic 1: Biological Principles Cells and the Organization of Life Characteristics of Life all living things share the following characteristics:

More information

Cell membrane. Multiple Choice Identify the choice that best completes the statement or answers the question.

Cell membrane. Multiple Choice Identify the choice that best completes the statement or answers the question. Cell membrane Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Which of the following types of molecules are the major structural components of the cell

More information

PART I: Neurons and the Nerve Impulse

PART I: Neurons and the Nerve Impulse PART I: Neurons and the Nerve Impulse Identify each of the labeled structures of the neuron below. A. B. C. D. E. F. G. Identify each of the labeled structures of the neuron below. A. dendrites B. nucleus

More information

Membrane Transport. Extracellular Concentration of X

Membrane Transport. Extracellular Concentration of X Use the following graph to answer questions 1 and 2. Rate of diffusion of X into the cell 1. Which of the following processes is represented by the above graph? c. Active transport 2. Molecule X is most

More information

Absorption of Drugs. Transport of a drug from the GI tract

Absorption of Drugs. Transport of a drug from the GI tract Absorption of Drugs Absorption is the transfer of a drug from its site of administration to the bloodstream. The rate and efficiency of absorption depend on the route of administration. For IV delivery,

More information

BIO.2 a) water chemistry and its impact on life processes; b) the structure and function of macromolecules BIO.3 d) the cell membrane model

BIO.2 a) water chemistry and its impact on life processes; b) the structure and function of macromolecules BIO.3 d) the cell membrane model Membrane Transport Lesson Plan Topic: Membrane Structure and Passive Transport NSES: Content Standard A: Students will learn the abilities necessary to do and understand scientific inquiry SOLs: Date:

More information

Biol 101 Exam 2: Cells & Cell Membranes Fall 2008

Biol 101 Exam 2: Cells & Cell Membranes Fall 2008 MULTIPLE CHOICE. There are 60 questions on this exam. All answers go on the Scantron. Choose the one alternative that best completes the statement or answers the question. 1. The cell theory is one of

More information

Basic Characteristics of Cells. Cell Structure and Function. Each Cell Has Three Primary Regions. Basic Characteristics of Cells. The Plasma Membrane

Basic Characteristics of Cells. Cell Structure and Function. Each Cell Has Three Primary Regions. Basic Characteristics of Cells. The Plasma Membrane Basic Characteristics of Cells Cell Structure and Function Chapter 3 Smallest living subdivision of the human body Diverse in structure and function Small Basic Characteristics of Cells Each Cell Has Three

More information

PSI Biology Membranes & Enzymes

PSI Biology Membranes & Enzymes Membranes Membranes, Diffusion Classwork 1. How does a phospholipid membrane create an isolated internal environment? 2. Draw and label a phospholipid. 3. In what way do the screen on a window and a cell

More information

MEMBRANE STRUCTURE AND FUNCTION

MEMBRANE STRUCTURE AND FUNCTION Chapter 5 The Working Cell: Membranes, Energy, and s Chapter 5: Big Ideas Cellular respiration Membrane Structure and Function Energy and the Cell How s Function MEMBRANE STRUCTURE AND FUNCTION Membranes

More information

Homeostasis and Transport Module A Anchor 4

Homeostasis and Transport Module A Anchor 4 Homeostasis and Transport Module A Anchor 4 Key Concepts: - Buffers play an important role in maintaining homeostasis in organisms. - To maintain homeostasis, unicellular organisms grow, respond to the

More information

Test Booklet. Subject: SC, Grade: 9- Quiz: Cell Processes. Student name:

Test Booklet. Subject: SC, Grade: 9- Quiz: Cell Processes. Student name: Test Booklet Subject: SC, Grade: 9- Quiz: Cell Processes Student name: Author: Jennifer Holm School: Lincoln High School Printed: Tuesday February 09, 2016 1 Which describes the cell theory? A Cells are

More information

Total body water ~(60% of body mass): Intracellular fluid ~2/3 or ~65% Extracellular fluid ~1/3 or ~35% fluid. Interstitial.

Total body water ~(60% of body mass): Intracellular fluid ~2/3 or ~65% Extracellular fluid ~1/3 or ~35% fluid. Interstitial. http://www.bristol.ac.uk/phys-pharm/teaching/staffteaching/sergeykasparov.htmlpharm/teaching/staffteaching/sergeykasparov.html Physiology of the Cell Membrane Membrane proteins and their roles (channels,

More information

Chapter 7: Membrane Structure and Function

Chapter 7: Membrane Structure and Function Name Period Concept 7.1 Cellular membranes are fluid mosaics of lipids and proteins 1. The large molecules of all living things fall into just four main classes. Name them. 2. Explain what is meant when

More information

Cell membranes and transport. Learning Objective:

Cell membranes and transport. Learning Objective: Cell membranes and transport Content Fluid mosaic model of membrane structure Movement of substances into and out of cells Learning Objective: a. Describe and explain the fluid mosaic model of membrane

More information

Cell Membrane Properties

Cell Membrane Properties Cell Membrane Properties Purpose of the lab: review the structure and function of the cell membrane understand the three types of transport across a membrane, and the special case of osmosis using Elodea

More information

Connexions module: m46021 1. The Cell Membrane. OpenStax College. Abstract. By the end of this section, you will be able to:

Connexions module: m46021 1. The Cell Membrane. OpenStax College. Abstract. By the end of this section, you will be able to: Connexions module: m46021 1 The Cell Membrane OpenStax College This work is produced by The Connexions Project and licensed under the Creative Commons Attribution License 3.0 By the end of this section,

More information

CELL MEMBRANE & CELL TRANSPORT (PASSIVE and ACTIVE) Webquest

CELL MEMBRANE & CELL TRANSPORT (PASSIVE and ACTIVE) Webquest Name: Period: CELL MEMBRANE & CELL TRANSPORT (PASSIVE and ACTIVE) Webquest PART I: CELL MEMBRANES WEBSITE #1: http://www.wisc-online.com/objects/index_tj.asp?objid=ap1101 1. What is the BASIC UNIT of LIFE?

More information

BR #5. What part of the cell controls whether or not a virus or nutrient enters? a) Mitochondria b) Nucleus c) Plasma membrane d) Chloroplast

BR #5. What part of the cell controls whether or not a virus or nutrient enters? a) Mitochondria b) Nucleus c) Plasma membrane d) Chloroplast BR #5 What part of the cell controls whether or not a virus or nutrient enters? a) Mitochondria b) Nucleus c) Plasma membrane d) Chloroplast Schedule: Notes: Membrane physiology Microscope Lab Essentials

More information

Todays Outline. Metabolism. Why do cells need energy? How do cells acquire energy? Metabolism. Concepts & Processes. The cells capacity to:

Todays Outline. Metabolism. Why do cells need energy? How do cells acquire energy? Metabolism. Concepts & Processes. The cells capacity to: and Work Metabolic Pathways Enzymes Features Factors Affecting Enzyme Activity Membrane Transport Diffusion Osmosis Passive Transport Active Transport Bulk Transport Todays Outline -Releasing Pathways

More information

Biological Membranes. Impermeable lipid bilayer membrane. Protein Channels and Pores

Biological Membranes. Impermeable lipid bilayer membrane. Protein Channels and Pores Biological Membranes Impermeable lipid bilayer membrane Protein Channels and Pores 1 Biological Membranes Are Barriers for Ions and Large Polar Molecules The Cell. A Molecular Approach. G.M. Cooper, R.E.

More information

Human Anatomy & Physiology I with Dr. Hubley. Practice Exam 1

Human Anatomy & Physiology I with Dr. Hubley. Practice Exam 1 Human Anatomy & Physiology I with Dr. Hubley Practice Exam 1 1. Which definition is the best definition of the term gross anatomy? a. The study of cells. b. The study of tissues. c. The study of structures

More information

Cell Structure and Function

Cell Structure and Function Bio 100 - Cells 1 Cell Structure and Function Tenets of Cell Theory 1. All living things are made up of one or more cells 2. Cells are the basic living units within organisms, and the chemical reactions

More information

Membranes very thin films of molecules that enclose cells, organelles, compartments

Membranes very thin films of molecules that enclose cells, organelles, compartments Membranes Overview Membranes very thin films of molecules that enclose cells, organelles, compartments Membrane composition Very different composition in prokaryotes and eukaryotes Typically composed of

More information

Proteins in Solution and in Membrane. - Proteins exist in solution or embedded in membranes

Proteins in Solution and in Membrane. - Proteins exist in solution or embedded in membranes Proteins in Solution and in Membrane - Proteins exist in solution or embedded in membranes 1 Soluble Proteins Physical and Chemical Properties of Soluble Proteins The folded conformations of native proteins

More information

to isolate specialized chemical processes in specific parts of the cell

to isolate specialized chemical processes in specific parts of the cell Intracellular transport in eukaryotes Overview Compartmentalization and inner membranes enables eukaryotic cells to be 1000-10000 times larger than prokaryotes to isolate specialized chemical processes

More information

Chapter 7: CELL MEMBRANE STRUCTURE AND FUNCTION

Chapter 7: CELL MEMBRANE STRUCTURE AND FUNCTION BIOLOGY I Chapter 7: CELL MEMBRANE STRUCTURE AND FUNCTION Evelyn I. Milian Instructor 2012 PLASMA MEMBRANE (Cell Membrane or Cytoplasmic Membrane) The plasma membrane is the cell s flexible outer limiting

More information

Ions cannot cross membranes. Ions move through pores

Ions cannot cross membranes. Ions move through pores Ions cannot cross membranes Membranes are lipid bilayers Nonpolar tails Polar head Fig 3-1 Because of the charged nature of ions, they cannot cross a lipid bilayer. The ion and its cloud of polarized water

More information

Membrane Structure and Function

Membrane Structure and Function Chapter 7 Membrane Structure and Function Lecture Outline Overview: Life at the Edge The plasma membrane separates the living cell from its surroundings. This thin barrier, 8 nm thick, controls traffic

More information

Cell Transport and Plasma Membrane Structure

Cell Transport and Plasma Membrane Structure Cell Transport and Plasma Membrane Structure POGIL Guided Inquiry Learning Targets Explain the importance of the plasma membrane. Compare and contrast different types of passive transport. Explain how

More information

Tutorial 2, Plasma Membrane

Tutorial 2, Plasma Membrane IPAM Cells and Materials: At the Interface between Mathematics, Biology and Engineering Tutorial 2, Plasma Membrane Dr. Toshikazu Hamasaki Dept. Bioengineering, UCLA Plasma Membrane Lipid Bi-layer Creates

More information

AP Biology-Chapter #6 & 7 Review

AP Biology-Chapter #6 & 7 Review DO NOT WRITE ON THIS TEST- USE ANSWER DOCUMENT AP Biology-Chapter #6 & 7 Review Multiple Choice Identify the choice that best completes the statement or answers the question. 1. All of the following are

More information

Nerves and Nerve Impulse

Nerves and Nerve Impulse Nerves and Nerve Impulse Terms Absolute refractory period: Period following stimulation during which no additional action potential can be evoked. Acetylcholine: Chemical transmitter substance released

More information

Study Guide. Explain how the genetic information in the nucleus is used to direct the production of proteins in the cytoplasm.

Study Guide. Explain how the genetic information in the nucleus is used to direct the production of proteins in the cytoplasm. Cells: The building blocks of life Study Guide Compare the following pairs of terms, noting the most significant differences: prokaryotic cells versus eukaryotic cells, plant cells versus animal cells.

More information

Student name ID # 2. (4 pts) What is the terminal electron acceptor in respiration? In photosynthesis? O2, NADP+

Student name ID # 2. (4 pts) What is the terminal electron acceptor in respiration? In photosynthesis? O2, NADP+ 1. Membrane transport. A. (4 pts) What ion couples primary and secondary active transport in animal cells? What ion serves the same function in plant cells? Na+, H+ 2. (4 pts) What is the terminal electron

More information

Quiz: Cell Organelles and Their Functions 1. This organelle functions in cellular respiration: lysosome endoplasmic reticulum mitochondrion golgi

Quiz: Cell Organelles and Their Functions 1. This organelle functions in cellular respiration: lysosome endoplasmic reticulum mitochondrion golgi Quiz: Cell Organelles and Their Functions 1. This organelle functions in cellular respiration: lysosome mitochondrion 2. The organelle functions to package and deliver proteins: lysosome mitochondrion

More information

CELL BIOLOGY CELL STRUCTURE, ORGANELLE, AND MEMBRANE TRANSPORT

CELL BIOLOGY CELL STRUCTURE, ORGANELLE, AND MEMBRANE TRANSPORT BIO 2401 CELL BIOLOGY page 1 CELL BIOLOGY CELL STRUCTURE, ORGANELLE, AND MEMBRANE TRANSPORT Cells = structural units of all living things; recognize one another by their surface proteins (called glycoproteins);

More information

CHARACTERISTICS OF PROKARYOTIC AND EUKARYOTIC CELLS

CHARACTERISTICS OF PROKARYOTIC AND EUKARYOTIC CELLS CHARACTERISTICS OF PROKARYOTIC AND EUKARYOTIC CELLS CHAPTER 4 Cellular Characteristics Cellular Characteristics 2 Domains, then Phyla 1 Domain, 4 kingdoms, then Phyla Prokaryotic Cells Sizes 0.5-2µm (average)

More information

Introduction to Body Fluids

Introduction to Body Fluids Introduction to Body Fluids Graphics are used with permission of: Pearson Education Inc., publishing as Benjamin Cummings (http://www.aw-bc.com) Page 1: Introduction to Body Fluids The fluids in your body

More information

Epithelial Tissue. Characteristics Functions Recognizing Epithelia Cell-to-cell junctions

Epithelial Tissue. Characteristics Functions Recognizing Epithelia Cell-to-cell junctions Epithelial Tissue Characteristics Functions Recognizing Epithelia Cell-to-cell junctions 4 Types of Tissue Epithelial Connective Muscle Neural Think of 2-3 basic functions for each. Characteristics of

More information

Carbon Hydrogen Oxygen Nitrogen

Carbon Hydrogen Oxygen Nitrogen Concept 1 - Thinking Practice 1. If the following molecules were to undergo a dehydration synthesis reaction, what molecules would result? Circle the parts of each amino acid that will interact and draw

More information

Parts of the Nerve Cell and Their Functions

Parts of the Nerve Cell and Their Functions Parts of the Nerve Cell and Their Functions Silvia Helena Cardoso, PhD [ 1. Cell body] [2. Neuronal membrane] [3. Dendrites] [4. Axon] [5. Nerve ending] 1. Cell body The cell body (soma) is the factory

More information

Chapter 4 Lecture Notes: Eukaryotic Cell Structure and Function

Chapter 4 Lecture Notes: Eukaryotic Cell Structure and Function Chapter 4 Lecture Notes: Eukaryotic Cell Structure and Function I. Overview: What is a eukaryote? A. Organisms whose cell/cells have a membrane-enclosed nucleus B. Have numerous other intracellular membranes

More information

COPYRIGHTED MATERIAL. Cells. Review. Structure and Function of the Cell

COPYRIGHTED MATERIAL. Cells. Review. Structure and Function of the Cell 8682-3 Ch02.F 12/15/00 9:34 AM Page 35 Cells Review Structure and Function of the Cell The cell is the basic functional unit of all living things. The plasma membrane (cell membrane) bounds the cell and

More information

Among a cell s most important activities are its interactions

Among a cell s most important activities are its interactions 6 Membranes Concept Outline 6.1 Biological membranes are fluid layers of lipid. The Phospholipid Bilayer. Cells are encased by membranes composed of a bilayer of phospholipid. The Lipid Bilayer Is Fluid.

More information

Plasma Membrane hydrophilic polar heads

Plasma Membrane hydrophilic polar heads The Parts of the Cell 3 main parts in ALL cells: plasma membrane, cytoplasm, genetic material this is about the parts of a generic eukaryotic cell Plasma Membrane -is a fluid mosaic model membrane is fluid

More information

Chapter 2: Cell Structure and Function pg. 70-107

Chapter 2: Cell Structure and Function pg. 70-107 UNIT 1: Biochemistry Chapter 2: Cell Structure and Function pg. 70-107 Organelles are internal structures that carry out specialized functions, interacting and complementing each other. Animal and plant

More information

Movement in and out of cells

Movement in and out of cells Movement in and out of cells Cells need to take in oxygen and nutrients for respiration. They also need to remove waste products such as CO 2. The cell membrane controls movement of materials. Generally,

More information

RAD 223. Radiography physiology. Lecture Notes. First lecture: Cell and Tissue

RAD 223. Radiography physiology. Lecture Notes. First lecture: Cell and Tissue RAD 223 Radiography physiology Lecture Notes First lecture: Cell and Tissue Physiology: the word physiology derived from a Greek word for study of nature. It is the study of how the body and its part work

More information

Modeling Membrane Movements

Modeling Membrane Movements Pillar: Active Living Division: IV Grade Level: 10 Core Curriculum Connections: Science 10 Health in Action Project Modeling Membrane Movements I. Rationale: The purpose of this activity is to provide

More information

BIOL 305L Laboratory Two

BIOL 305L Laboratory Two Please print Full name clearly: Introduction BIOL 305L Laboratory Two Osmosis, because it is different in plants! Osmosis is the movement of solvent molecules through a selectively permeable membrane into

More information

1. How do passive and active transport differ from each other?

1. How do passive and active transport differ from each other? 1. How do passive and active transport differ from each other? Passive transport Does not require the use of energy. Moves solutes and solvents across a cell membrane, from higher to lower concentration.

More information

Cellular Structure and Function

Cellular Structure and Function Chapter Test A CHAPTER 7 Cellular Structure and Function Part A: Multiple Choice In the space at the left, write the letter of the term or phrase that best answers each question. 1. Which defines a cell?

More information