Cells Play a Vital Role In Living Things. Chapter 1: Topic 2

Transcription

1 Cells Play a Vital Role In Living Things Chapter 1: Topic 2

2 are the smallest known functioning unit of life. All organisms must be made of at least cell. Cells with a similar structure And function are organized into. Tissues that work together for a common purpose form. An is a group of organs that work Together for a common purpose in order to keep you alive.

3 Cell structures that you can see with a microscope CELL STRUCTURE FEATURE THAT YOU CAN HELP IDENTIFY WHAT YOU ARE LOOKING AT Looks like a thin line that surrounds the whole cell A rigid, frame-like covering that surrounds the cell membrane A liquid inside the cell, which has grainylooking bits in it A fairly large, dark, spherical structure that s usually near the centre of the cell Clear, liquid filled spaces in various places within the cytoplasm (Great picture of Plant & Animal cells on pg. 109 in your textbook)

4 Viewing Plant and Animal Cells are specialized structures within each cell. One way to think about cells is living factories making all the necessary things for them to live

5 Cells STRUCTURE FUNCTION A command center that directs all cellular activities such as movement and growth The powerhouse of the cell where chemical reactions occur that convert energy into a form it can use A controllable gateway that lets needed materials in and waste out The storage rooms for nutrients and water are stored The kitchen of the cell. It contains the nutrients required by the cell to maintain its life processes The frame of the cell. This provides strength for the cell The solar panels of the cell. They carry out photosynthesis

6 Picture on an cell.

7 Picture on a cell.

8 Differences between Plant and Animal cells 1) List 3 differences found between a Plant and Animal cells? 2) Why is there a difference between Plant and Animal cells?

9 Plant OR Animal Cell Model Project

10 TOPIC 2.3 Organisms can be singlecelled or multi-celled The smallest known organism is the. The largest known organism is the blue whale

11 are the individual, living units that make up all living organisms. Some organisms are: 1. this means they are made up of two or more cells (Ex. Plants & Animals) 2. this means they are made up of only a single cell (Ex. Diatoms, Mycroplasma, Amoeba, Paramecium) Most micro-organisms are unicellular (like Mycoplasma)

12 Unicellular Organisms are single-celled plants They have chloroplasts just like all other plants They live in lakes, oceans and moist soil

13 Unicellular Organisms Live in water Move around and eat using foot-like projections called psuedopods Live in fresh water Covered with hair like structures called cilia used to move

14 Simple????? NO!!! Uni-cellular organisms can do most things we do Eat, move, react to stimuli, get rid of waste, reproduce (also ALL 6 CHARACTERISTICS OF LIVING THINGS) Uni-cellular organisms develop specialized structures to help them do these functions.

15 Multi-cellular Organisms Multi-cellular organisms rely on specialized cells to perform functions All cells in multi-cellular organisms interact and depend on each other EXAMPLE A multicelled animal such as a deer, there are cells specialized for the function of feeding. However, these cells are dependent on other specialized cells, such as muscle cells, to move the deer to new supplies of food.

16 TOPIC 2.3 Check and Reflect 1. Unicellular organisms are simple. Agree or disagree with this statement and fully explain your answers. 2. Why can t the individual cells of a multicellular organism live on their own? Explain. 3. Identify an amoeba s food-gathering structures and describe how they function.

17 Topic 2.4 how substances move in and out of cells Right now, every cell in your body is bringing in,, and inside itself At the same time, each is waste products from inside itself. This bringing in and removal of substances is for survival!!!!! These processes occur in organisms, not just humans

18 The cell structure that controls what substances go in and out of the cell is the. Many substances move through the cell membrane by a process called.

19 Diffusion : moves particles from a more concentrated area to a less concentrated area Diffusion is a balancing out process that continues until the concentration of particles is the everywhere

20 Activity We are going to watch diffusion in action: We need 1 beaker of room temperature water, some food coloring and a stop watch Watch what happens to the water in 20 seconds 60 seconds 10 minutes PREDICT

21 Diffusion of many substances move in and out of cells by diffusion The cell membrane has tiny openings that allow particles to pass through These openings are small enough to keep the cell s and inside.

22 :refers to the cell membrane only allowing certain things to go in and out of a cell Example: A mitochondria needs oxygen to do its job the cell membrane lets oxygen pass through Concentration of oxygen is usually higher outside of the cell membrane than it is inside

23 Water Water is another substance that has particles small enough to diffuse through the cell membrane Water must stay constant in the cell If the water gets too low inside the cell, water from outside of the cell diffuses in. If the water gets too high inside the cell, the water diffuses out of the cell Water is essential to the cells survival The movement of water through a selectively permeable membrane is called

24 WHICH WAY WILL THE WATER PARTICLES TRAVEL? HIGH CONCENTRATION (WHERE THERE ARE MORE WATER PARTICLES) -> LOW CONCENTRATION (WHERE THERE ARE LESS WATER PARTICLES)

25 Effects of Osmosis on a Cell

26 CHECK AND REFLECT 1a) Use the term selectively permeable in a sentence b)what is the function of a cell s selectively permeable membrane? 2. The terms diffusion and osmosis seem to have similar meanings. Explain how they are similar. 3. Fish species that live in fresh water have to remove excess water as waste from their bodies. Fish species that live in salt water have bodies that keep as much water as possible. Using what you know about osmosis, explain these observations.

27 Topic 2.5 Cells in multi-cellular organisms combine to form tissues and organs Uni-cellular organisms are tiny because there are limits to how large they can grow This is because of osmosis and diffusion These processes work best over distances It takes an oxygen particle a fraction of a second to diffuse over a distance of 0.01mm. To diffuse over a distance of 1 mm would take!

28 Cells Reproduce All organisms grow and develop So they get BIGGER When they reach the limits of their size, they EXAMPLE: Amoeba This is how our cells reproduce too! (your Body replaces or so skin cells that it naturally loses each day)

29 Multi-cellular organisms have SPECIALIZED cells there are many kinds of cells and each kind carries out a specific function needed to support life. Each kind of cell has specific structures that enable it to carry out its function Example, the function of a red blood cell is to FACT: When red blood cells mature they lose their nucleus so cannot reproduce!

30 Our bones contain that has specialized cells that make red blood cells

31 Four types of tissues Tissue Supports and connects different parts of the body (fat, cartilage, bones, tendons) Tissue Covers the surface of your body and the outside of your organs. Lines the inside of some organs (Skin) Tissue Makes up the brain, spinal cord and nerves Tissue Allows you to move

32 Three Types of Plant Tissues (Pg. 123) Tissue Uses sunlight to produce sugar that the plant uses for energy Tissue Waterproof layer to protect plant Tissue Tube-like cells with hollow centers to carry water

33 Check and Reflect 1. Is a red blood cell more specialized than an amoeba, or is it the other way around? 2. What are the advantages of having specialized cells? Are there disadvantages?