Levels of Structural Organization

Transcription

1 HD in Nursing Studies-Human Biology Levels of Structural Organization Structural and Functional Organization of the Human Body Chemical atoms combined to form molecules Cellular cells are made of molecules Tissue consists of similar types of cells Organ made up of different types of tissues Organ system consists of different organs that work closely together Organismal made up of the organ systems Levels of Structural Organization Organ Systems of the Body Integumentary system Forms the external body covering Composed of the skin, sweat glands, oil glands, hair, and nails Protects deep tissues from injury and synthesizes vitamin D

2 Skin Structure Organ Systems of the Body Skeletal system Composed of bone, cartilage, and ligaments Protects and supports body organs Provides the framework for muscles Site of blood cell formation Stores minerals Bones and Cartilages of the Human Body Organ Systems of the Body Muscular system Composed of muscles and tendons Allows manipulation of the environment, locomotion, and facial expression Maintains posture Produces heat

3 Skeletal Muscle Major Skeletal Muscles Organ Systems of the Body Simplified Design of the Nervous System Nervous system Composed of the brain, spinal column, and nerves Is the fast-acting control system of the body Responds to stimuli by activating muscles and glands

4 Organ Systems of the Body Gross Anatomy of Heart: Frontal Section Cardiovascular system Composed of the heart and blood vessels The heart pumps blood The blood vessels transport blood throughout the body Veins of Systemic Circulation Aorta and Major Arteries

5 Organ Systems of the Body Lymphatic System: Overview Lymphatic system Composed of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels Picks up fluid leaked from blood vessels and returns it to blood Disposes of debris in the lymphatic stream Houses white blood cells involved with immunity Organ Systems of the Body The Components of the Respiratory System Respiratory system Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs Keeps blood supplied with oxygen and removes carbon dioxide

6 Organ Systems of the Body The Components of the Digestive System Digestive system Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, and liver Breaks down food into absorbable units that enter the blood Eliminates indigestible foodstuffs as feces Organ Systems of the Body The Urinary System Organs Urinary system Composed of kidneys, ureters, urinary bladder, and urethra Eliminates nitrogenous wastes from the body Regulates water, electrolyte, and ph balance of the blood

7 Organ Systems of the Body Male Reproductive System Male reproductive system Composed of prostate gland, penis, testes, scrotum, and ductus deferens Main function is the production of offspring Testes produce sperm and male sex hormones Ducts and glands deliver sperm to the female reproductive tract Organ Systems of the Body Female Reproductive Anatomy Female reproductive system Composed of mammary glands, ovaries, uterine tubes, uterus, and vagina Main function is the production of offspring Ovaries produce eggs and female sex hormones Remaining structures serve as sites for fertilization and development of the fetus Mammary glands produce milk to nourish the newborn

8 Organ System Interrelationships Organ System Interrelationships The integumentary system protects the body from the external environment Digestive and respiratory systems, in contact with the external environment, take in nutrients and oxygen Nutrients and oxygen are distributed by the blood Metabolic wastes are eliminated by the urinary and respiratory systems HD in Nursing Studies-Human Biology Cell Theory Cellular Physiology The cell is the basic structural and functional unit of life Organismal activity depends on individual and collective activity of cells Biochemical activities of cells are dictated by subcellular structure Continuity of life has a cellular basis

9 Structure of a Generalized Cell Plasma Membrane Separates intracellular fluids from extracellular fluids Are selectively permeable Plays a dynamic role in cellular activity Glycocalyx is a glycoprotein area abutting the cell that provides highly specific biological markers by which cells recognize one another Fluid Mosaic Model Phospholipid Molecules Clothespin shape The head (phosphate portion) relatively soluble in water (polar, hydrophilic). The tails (the lipids) relatively insoluble (non-polar, hydrophobic) & meet in the interior of the membrane.

10 Fluid Mosaic Model Fluid Mosaic Model Integral proteins --embedded in the membrane Peripheral proteins --loosely bound to the inner or outer surface Anchored proteins Double bilayer of lipids with imbedded, dispersed proteins Bilayer consists of phospholipids, cholesterol, and glycolipids Glycolipids are lipids with bound carbohydrate Phospholipids have hydrophobic and hydrophilic bipoles Functions of Membrane Proteins Functions of Membrane Proteins Transport Enzymatic activity Receptors for signal transduction Intercellular adhesion Cell-cell recognition Attachment to cytoskeleton and extracellular matrix

11 Phospholipid Membrane Passive Membrane Transport: Diffusion Simple diffusion nonpolar and lipidsoluble substances Diffuse directly through the lipid bilayer Diffuse through channel proteins Selective permeability regulates the type & rate of molecules traffic into and out of the cell Passive Membrane Transport: Diffusion Passive Membrane Transport: Osmosis Facilitated diffusion large, polar molecules such as simple sugars Combine with protein carriers Occurs when the concentration of a solvent is different on opposite sides of a membrane Diffusion of water across a semipermeable membrane Osmolarity total concentration of solute particles in a solution

12 Effect of Membrane Permeability on Diffusion and Osmosis Effect of Membrane Permeability on Diffusion and Osmosis Passive Membrane Transport: Filtration Sodium-Potassium Pump The passage of water and solutes through a membrane by hydrostatic pressure Pressure gradient pushes solute-containing fluid from a higher-pressure area to a lower-pressure area

13 Active Transport Uses ATP to move solutes across a membrane Requires carrier proteins Membrane Transport System Symport system two substances are moved across a membrane in the same direction Antiport system two substances are moved across a membrane in opposite directions Membrane Transport System Primary active transport hydrolysis of ATP phosphorylates the transport protein causing conformational change Membrane Transport System Secondary active transport use of an exchange pump (such as the Na + -K + pump) indirectly to drive the transport of other solutes Na +, K + -pump [ K + ] low Carrier proteins [ Na + ] high [ K + ] high [ Na + ] low Carrier proteins involved in transporting molecules uphill against an electrochemical gradient from a region of low concentration to a region of high concentration.

14 Vesicular Transport Vesicular Transport Transport of large particles and macromolecules across plasma membranes Exocytosis moves substance from the cell interior to the extracellular space Endocytosis enables large particles and macromolecules to enter the cell Receptor-mediated transport uses clathrin-coated pits as the major mechanism for specific uptake of macromolecules HD in Nursing Studies-Human Biology Homeostasis Homeostasis is the maintenance of relatively constant conditions within the body's internal environment. Homeostasis

15 Homeostasis Homeostasis Homeostasis Bring a deviation in a physiological event back into line. Homeostasis A response which further enhances the change that set it in motion.

16 Negative Feedback In negative feedback systems, the output shuts off the original stimulus Example: Regulation of blood glucose levels Positive Feedback In positive feedback systems, the output enhances or exaggerates the original stimulus Example: Regulation of blood clotting