Study Guide Essay

Submitted By Lauren-Brand
Words: 2902
Pages: 12

Anatomy and Physiology Exam 1- Figueroa

Balance = equilibrium = dynamic process found in all living systems endocrine and nervous system works together for this constantly adjusting to maintain a relatively constant condition
Large changes exterior, small changes interior to the body ex. blood pressure, glucose levels, and body temp
Homeostatic Control Mechanism- imbalance balance
1. Stimulus reacts to change
2. Change detected by receptor
3. Receptor inputs information along afferent pathway  control center
4. Output information to effector
5. Response of effector back to homeostasis

Body fluids
Intracellular fluid- the inside our cells
Extracellular fluid- all body fluids outside the cell interstitial fluid- fluid between cells in tissue plasma- the fluid component of blood lymph- the fluid in our lymphatic vessels cerebrospinal fluid (CSF)- the fluid within the CNS
Synovial fluid- the fluid within most joints

Negative Feedback System most IMPORTANT feedback system = focus more on this type for test
“Negative” because it gives an opposite response for example: if blood pressure is too high, you need to lower it (one way is by vasodilation or the expansion of blood vessels which lowers pressure)
3 essential components receptor- detects changes in controlled conditions control center- decide the type and amount of the response the body needs sends signals to the effector effector- reacts to signals from the control center and produces the required response
Ex. Body Temp if the body temperature is too high or too low, it can cause different system disorders normal temp: 98.6C thermoreceptors: detect both increasing and decreasing body temps they then send impulses to the brain neurons in the hypothalamus control heat balance if too hot: sweat glans are stimulated if too cold: you shiver/ shake

Positive Feedback System
“Positive” because it continues/ enhances the direction in which stimulus is going must be stopped or limited by an OUTSIDE event
Ex. Control of Labor contractions begin receptors realize that the cervix is being stretched so it tells the control center the control center sends signals to the effectors to contract the muscles even more stopped once the baby is born/ leaves the body

Blood pressure regulation- 3 components
Baroreceptors- detects change in blood pressure to communicate with the brain
Brain- interprets info to send to heart and blood
Heart and blood vessels- take info from brain and alteres the pressure
Beta cells in hyperglycemia
Alpha cells in hypoglycemia

Cells are made of 3 pars
1. plasma membrane- flexble outer surface of the cell
2. cytoplasm- numerous organelles surrounded by cytosol
3. nucleus- large organelle with DNA and the cells chromosomes

The Plasma Membrane
The fluid mosaic model
Membrane lipids
Lipid bilayer forms the fabric of the membrane
Composed of phospholipid molecules
Head = polar and hydrophilic (philic means it likes water/ if water soluble)
Tail = hydrophobic (phobice means it is afraid of water/ insoluble in water). Uncharged, nonpolar. It is made up of two fatty acid chains

Membrane Proteins
Integral proteins: firmly inserted into the lipid bilayer some only protrude from only one membrane surface most are transmembrane: span the entire width of the membrane and stick out both sides most are involved in transport some clump together to form channels, or pores, through which water-soluble molecules or ions can move through others are carriers that bind to a substance and then move it through the membrane receptors Peripheral proteins: are not embedded in the lipid they attach loosely to integral proteins
transport from one side to the other enzymatic activity substrate to produce products
Receptors for signal transduction

Membrane Transport
Rate of diffusion primarily depends on concentration gradient (highlow)
Passive process= no energy used
Diffusion: the tendency of molecules or ions to move from