Exam 1 Flashcards
Physiology is the study of
functions of living things
Physiology has two approaches, one with an emphasis on ______ and one with an emphasis on ______
on purpose of body process (Why?)
• Explanations are in terms of meeting a bodily need
on mechanism (How?) • Explanations are in terms of cause and effect sequences
Physiology is the brother of
Anatomy
o Structure-Function relationships of the body include:
- Heart receiving and pumping blood
- Teeth tearing and grinding food
- Bones protect vital organs
- Vessels carrying blood
Levels of organization
Chemical •Molecules composed of atoms Cellular •Cells are basic units of life Tissue (group of cells) Organ (one or more tissues make up an organ) Body system (one or more organs make up a body system) Organism
What are the seven basic cell functions?
o Obtain nutrients and oxygen from surrounding environment (Things that do not have nutritional value are things that would not keep you alive on a desert island)
o Perform chemical reactions that provide energy for the cell
o Eliminate carbon dioxide and other wastes to surrounding environment
o Synthesize needed cellular components
oRegulate exchange of materials between cell and its surrounding environment
o Sensing and responding to changes in surrounding environment
o Reproduction
-Exception Nerve cells and muscle cells lose their ability to reproduce early in development
What are the 4 primary types of tissue?
- Muscle tissue
- Nervous tissue
- Epithelial tissue
- Connective tissue
What are the 3 types of muscle tissue and their function?
Skeletal muscle • Moves the skeleton Cardiac muscle • Pumps blood out of the heart Smooth muscle • Encloses and controls movement of contents through organs
Muscle tissue is specialized for ______ and facilitates ______
contracting
movement
Nervous tissue consists of cells specialized for _________
initiating and transmitting electrical impulses
Nervous tissue is found in _______(3 places)
brain, spinal cord, and nerve cells
Epithelial tissue consists of cells specialized for _______
exchanging materials between the cell and its environment
Epithelial tissue connects the body and its organs to ________
the environment
Epithelial tissue is organized into two general types of structures:
- Epithelial sheets
* Secretory glands
the purpose of connective tissue?
Connects, supports, and anchors various body parts
connective tissue is distinguished by having _________
relatively few cells dispersed within an abundance of extracellular materials
three examples of connective tissue:
- Tendons- attach skeletal muscle to bones
- Bone- supports and protects the body
- Blood- transports bodily materials
organs generally consist of what?
two or more types of tissues that work together to perform a particular function
The stomach consists of four different tissue types. Name them and their function as part of the stomach
- Inside of stomach lined with epithelial tissue
- Wall of stomach contains smooth muscle
- Nervous tissue in stomach controls muscle contraction and gland secretion
- Connective tissue binds all the above tissues together
Body Systems-
Groups of organs that perform related functions and interact to accomplish a common activity essential to survival of the whole body
Name the 11 systems of the human body
- Circulatory System
- Digestive System
- Respiratory System
- Urinary System
- Skeletal System
- Muscular System
- Integumentary System (hair, skin, nails)
- Immune System
- Nervous System
- Endocrine System
- Reproductive System
Homeostasis is the ability to maintain a _________, NOT a ____________
relatively stable internal environment
constant internal environment
_________ is essential for survival and function of all cells
homeostasis
Each cell contributes to maintenance of a relatively stable internal environment to maintain ________
homeostasis
Body cells are contained in a ________ through which life-sustaining exchanges are made
watery internal environment
Extracellular fluid (ECF)-
Fluid environment in which the cells live (fluid outside the cells)
The two components of ECF-
plasma
interstitial fluid
Intracellular fluid ICF
Fluid contained within all body cells
the seven factors homeostatically regulated are:
- Concentration of nutrient molecules
- Concentration of O2 and CO2
- Concentration of waste products
- pH
- Concentration of water, salt, and other electrolytes
- Volume and pressure
- Temperature
The circulatory system contributes to homeostasis by?
Carries materials from one part of the body to another
The digestive system contributes to homeostasis by? (3 things)
- Breaks down dietary food into smaller molecules that can be distributed to body cells
- Transfers water and electrolytes from external environment to internal environment
- Eliminates undigested food residues to external environment in the feces
The respiratory system contributes to homeostasis by? (2 things)
- Gets O2 from and eliminates CO2 to the external environment
- Important in maintenance of proper pH of internal environment
The urinary system contributes to homeostasis by?
• Removes excess water, salt, acid, and other electrolytes from plasma and eliminates them in urine.
Gout-
- accumulation of uric acid in the blood. Causes severe joint pain
If you are severely dehydrated, drink ____ because ______
gatorade
it makes you drink more
How does the skeletal system work to maintain homeostasis? (4 things)
- Provides support and protection for soft tissues and organs
- Serves as storage reservoir for calcium
- Along with muscular system enables movement of body and its parts
- Bone marrow is ultimate source of all blood cells
How does the muscular system work to maintain homeostasis?
moves the bones
How does the integumentary system work to maintain homeostasis? (2 things)
- Serves as outer protective barrier
* Important in regulating body temperature
How does the immune system work to maintain homeostasis? (2 things)
- Defends against foreign invaders and against body cells that have become cancerous
- Paves way for repairing or replacing damaged or worn-out cells
How does the nervous system work to maintain homeostasis? (2 things)
- Controls and coordinates bodily activities that require rapid responses-reflexes.
- Detects and initiates reactions to changes in external environment
How does the endocrine system work to maintain homeostasis? (2 things)
- All hormone-secreting glands. Regulate numerous cellular activities
- Especially important for controlling concentration of nutrients and, by adjusting kidney function, controls internal environment’s volume and electrolyte composition
How does the reproductive system work to maintain homeostasis? (tricky, 2 things)
- Not essential for homeostasis (not essential for survival of individual)
- Is essential for perpetuating the species
Leukemia-
cancer of the bone marrow. Abnormal accumulation of white blood cells. Lack of platelets. Blood clotting is affected
Glucagon and insulin. Which is more essential and why?
• Glucagon is more essential than insulin. It has 11 genes that do the same thing as it does. You cannot survive if your brain doesn’t have sugar.
In order to maintain homeostasis, homeostatic control systems must be able to: (3 things)
- Detect deviations from normal in the internal environment that need to be held within narrow limits
- Integrate this information with other relevant information
- Make appropriate adjustments in order to restore factor to its desired value
disruptions to homeostasis can lead to
illness and death
Pathophysiology-
Abnormal functioning of the body associated with disease
Name three important roles of the plasma membrane:
o Controls movement of molecules between the cell and its environment
o Participates in joining cells to form tissues and organs
o Plays important role in the ability of a cell to respond to changes in the extracellular environment
The most abundant lipids of the plasma membrane are _______
phospholipids
Amphipathic-
having both a polar and nonpolar portion
carbohydrates are located on which side of cell membrane?
outer surface (extracellular) only
where is cholesterol located in the cell membrane and what does it contribute to?
- Tucked between phospholipid molecules
* Contributes to fluidity and stability of cell membrane
Name five functions of membrane proteins:
- Span membrane to form water-filled pathways, or channels across lipid bilayer
- Serve as carrier molecules
- Membrane-bound enzymes
- Receptor sites
- Cell adhesion molecules (CAMs)
- Proteins on surface are important in cell-to-cell interaction/ recognition
which part of the phospholipid bilayer prevents solutes from crossing?
the hydrophobic interior
Membrane carbohydrates serve as _____
self-identity markers which enable cells to identify and interact with one another
Different carbohydrate concentrations on the membrane can be found in different _____
cell types
Name the 3 means by which cells are held together:
- extracellular matrix
- Cell adhesion molecules in cells’ plasma membranes
- Specialized cell junctions
extracellular matrix seves as biological “_____”
glue
three major types of protein fibers interwoven in extracellular matrix:
collagen, elastin, fibronectin
Collagen-
protein that forms flexible fibers or sheets
Scurvy-
vitamin C deficiency. Causes collagen fibers to be damaged. Results in bleeding in skin and mucous membranes.
Elastin-
Rubbery protein fiber. Abundant in lung tissue. Promotes flexibility.
Fibronectin-
Promotes cell adhesion. Holds cells in position. Reduced production in cancer cells that break free and metastasize
What two properties of particles influence whether they can cross cell membrane without assistance?
- Relative solubility of particle in lipid
* Size of the particle
un-assisted membrane transport is called:
diffusion or osmosis
The four assisted membrane transports are:
- Carrier-mediated transport
- Facilitated transport
- Active transport
- Vesicular transport
Diffusion-
uniform spreading out of molecules due to their random intermingling
The tonicity of the extracellular solution determines what about a cell?
whether it will swell, shrink, or remain the same
Which assisted membrane transport requires that the carrier undergo a conformational change?
carrier-mediated transport
Carrier-mediated transport can be active or passive, depending on ______
concentration gradients
Characteristics that determine the kind and amount of material that can be transferred across the membrane via carrier-mediated transport:
- Specificity
- Saturation
- Competition
Facilitated diffusion is an assisted membrane transport that falls under the sub-category of ______ transport.
carrier-mediated
Active transport is also in the sub-category of _____ transport just like facilitated diffusion, with the key differences being that active transport moves molecules ________ their concentration gradient
carrier-mediated
against
primary active transport requires _____, while secondary active transport is driven by _____
- ATP
- An ion concentration gradient established by a primary active transport system
Vesicular transport-
Material is moved into or out of the cell wrapped in membrane
Pinocytosis-
“cell drinking” nonselective uptake of extracellular fluid droplets
Phagocytosis-
-“cell-eating” selective uptake of solid particles
Exocytosis-
Provides mechanism for secreting large molecules
Most depression medications, such a Prozac, are SSRI’s, which stands for
Selective Serotonin Re-Uptake Inhibitors
• Serotonin is a neurotransmitter in the _______ nervous system. Produces a feeling of __________
central
pleasure, euphoria, and general well-being.
Many people who suffer from depression are deficient in ________
Serotonin
How do SSRI’s treat depression?
SSRI’s block Endocytosis, so instead of serotonin binding the receptor and being taken into neuron B, it is allowed to keep binding the serotonin receptor, producing a constant feeling of well-being.
Membrane potentials are in reference to the inside/outside of a cell?
inside
Resting membrane potential-
Constant membrane potential present in cells of non-excitable tissues and those of excitable tissues when they are at rest
The _________ is the most important active transport system, and helps contribute to the ____________
Na+/ K+ ATPase
resting membrane potential of some cells
How the Na+/ K+ ATPase works:
It binds ______ from the cytosol, then undergoes a conformational change after being phosporylated by ATP. Following the conformational change, __________ Dephosphorylation returns the transporter to original conformation, and ________
- 3 Na+
- 3 Na+ are released to extracellular and 2 K+ are picked up
- K+ is released to cytosol
Effect of sodium-potassium pump on membrane potential makes a small/large contribution to membrane potential?
small
The biggest influence on resting membrane potential is _________
the relative permeability, or “leakiness” of ion channels.
Why does K+ desire an equilibrium potential of -90?
- The concentration gradient for K+ tends to move this ion out of the cell.
- The outside of the cell becomes more positive as K+ ions move to the outside down their concentration gradient.
- The membrane is impermeable to the large intracellular protein anion (A-). The inside of the cell becomes more negative as K+ ions move out, leaving behind A-..
- The resulting electrical gradient tends to move K+ into the cell
- No further net movement of K+ occurs when the inward electrical gradient exactly counterbalances the outward concentration gradient. The membrane potential at this equilibrium point is the equilibrium potential for K+ (EK+ ) at -90 mV.
Why does Na+ desire an equilibrium potential of +60?
- The concentration gradient for Na+ tends to move this ion into the cell
- The inside of the cell becomes more positive as Na+ ions move to the inside down their concentration gradient
- The outside becomes more negative as Na+ ions move in, leaving behind in the ECF unbalanced negatively charged ions, mostly Cl-.
- The resulting electrical gradient tends to move Na+ out of the cell
- No further net movement of Na+ occurs when the outward electrical gradient exactly counterbalances the inward concentration gradient. The membrane potential at this equilibrium point is the equilibrium potential for Na+ (ENa+) at +60 mV.
Equilibrium potential-
The membrane potential for a particular ion in which the chemical gradient and the electrical gradient completely balance each other out.
Its important to keep in mind that the membrane potential will ALWAYS be closest in value to the ________________
equilibrium potential of the most permeable ion at that time
the resting membrane potential is -70 mV, because the membrane is ___ times more permeable to K+ than to Na+
30
o Since relative ion concentrations are constantly varying, one would expect the equilibrium potential for individual ions to vary as well. So, how is the equilibrium potential (Eion) calculated?
The Nernst Equation
The nernst equation allows you to calculate ______ if ________ is known.
equilibrium potential
the relative ion concentrations are known.
The Nernst Equation is defined as:
E(ion) = 61/z log [(ion conc. outside cell)/(ion conc. inside cell)]