SLCC 2420 PHYSIOLOGY FINAL EXAM
QUESTIONS AND ANSWERS
CH. 1 Organizational levels of the body - Answer-Cell, Tissue, Organ, Organ System
Cell and tissue types - Answer-1. Neurons / Nervous Tissue
2. Muscle cells / Muscle Fibers
3. Epithelial cells / Epithelium
4. Connective tissue
Functions of the organ systems - Answer-See table 1.1
Internal and external environments - Answer-*Internal: Immediate environment of most
cells*
- Includes plasma and interstitial fluid (ISF)
*External: External side of epithelial body barrier*
- Includes Skin & Lumens of organs with contact of external environment
Body fluid compartments - Answer-
Homeostasis and how it is maintained - Answer-Negative feedback
Negative feedback and positive feedback - Answer-*Negative* = Main mechanism used
to maintain homeostasis.
Acts opposite of variable to return body to homeostasis.
*Positive* = Response in the same direction as change (Moves variable further away
from normal set point value)
Components of a feedback loop - Answer-Sensors -> Integrating Center -> Effectors
CH. 2 Nonpolar and polar covalent bonds, hydrogen bonds, ionic bonds - Answer-
*Nonpolar* = Electronegativity of the atoms are equal
*Polar* = Pair of electrons is unequally shared between two atoms.
*Hydrogen* = A weak bond resulting from an electrostatic attraction between a proton in
one molecule and an electronegative atom in the other.
*Ionic* = Complete transfer of valence electrons between atoms. Generates 2
oppositely charged ions. The metal loses electrons to become a positively charged
cation, whereas the nonmetal accepts those electrons to become a negatively charged
anion.
Which types of molecules are hydrophilic and which are hydrophobic - Answer-
Hydrophilic =Carbohydrates, Polar & Ionic molecules
Hydrophobic = Lipids, Nonpolar molecules
Ampipathic = contains both Philic & Phobic properties
,Acids, bases, buffers, and pH - Answer-Acids - Release H+ when dissolved in water
Bases - Accept or remove H+
Buffers - Can both accept and donate hydrogen ions
- Absorb H+ if body fluid pH too acidic
- Release H+ if body fluid pH too basic
pH = -log [H+]
Characteristics and functions of carbohydrates, lipids, proteins, and nucleic acids -
Answer-*Carbs* - Polar, Hydrophilic / Energy source, part of cell membrane
*Lipids* - Nonpolar, Hydrophobic (sometimes ampipathic) / Composed primarily of
hydrogen and carbon atoms
*Proteins* - Polymers of amino acids with peptide bonds / Receptors, carrier proteins,
enzymes, hormones (ex. insulin,) contractile proteins (actin and myosin,) antibodies,
structural proteins
*Nucleic Acids*- Polymers of nucleotides / DNA, RNA, Storage and expression of
genetic information
Cell structure: plasma membrane, nucleus, and organelles - Answer--Phospholipid
bilayer, selectively permeable, fluid mosaic model (moveable)
-Nucleus contains genetic information
Cell-to-cell adhesions: - Answer-Tight junctions, Gap junctions, Desmosomes
Tight junctions - Answer-- Impermeable barrier between epithelial cells lining lumens
- Solutes can only go through the cells but not around them
Gap junctions - Answer-- Channels that allow cells to communicate or exchange
nutrients
Ex. Cardiac muscle, smooth muscle, bone, some neurons
Desmosomes - Answer-- Keeps tissues from tearing apart when mechanically
stressed. (Like a spot weld)
- Found in skin, heart, uterus
CH. 3/21 Anabolic versus catabolic reactions - Answer-Anabolic = Involves the
production of larger molecules from smaller reactants.
Catabolic = Involves breakdown of larger molecules into smaller ones.
Endergonic versus exergonic reactions - Answer-Endergonic = Requires energy
Exergonic = Releases energy
Types of chemical reactions: - Answer-1. Hydrolysis and condensation reactions
2. Phosphorylation and dephospho rylation reactions
3. Oxidation-reduction reactions
,Hydrolysis and condensation reactions - Answer-*Hydrolysis* - Water reacts with
molecules, breaking the bonds that link a molecule together.
*Condensation* - Reverse of Hydrolysis; Joining together two or more smaller
molecules to form a larger one.
Phosphorylation and dephosphorylation reactions - Answer-*Phosphorylation* - Addition
of a phosphate group to ADP to synthesize ATP.
*Dephosphorylation* - Removal of a phosphate group from ATP to form ADP.
Oxidation-reduction reactions - Answer-*Oxidation* - Removes electrons from an atom
or molecule
*Reduction* - Electrons removed are accepted by another atom or molecule
Law of mass action - Answer-Increase in the concentration of reactants relative to
products tends to push a reaction forward, and an increase in the concentration of
products relative to reactants tend to push a reaction in reverse.
Activation energy - Answer-The difference between the energy of the transition state
and the energy of either the reactants or the products.
How enzymes work - Answer-Biomolecules specialized to act as catalysts (increase
rate of chemical reactions)
Factors that affect enzyme activity: - Answer-1. Substrate concentration and enzyme
concentration
2. Enzyme's affinity for the substrate
3. Temperature and pH
Enzyme regulation - Answer-Allosteric & Covalent regulation
Allosteric regulation - Answer-Reversible binding of a modulator molecule to a
regulatory site on an enzyme.
Covalent regulation - Answer-Enzyme changes shape at active site (permanent)
Protein kinase and phosphatase enzymes - Answer-Kinase - Turns on, or
phosphorylates a target enzyme molecule
Phosphatase - Turns off, or dephosphorylates a target enzyme molecule
Feedback inhibition and feedforward activation - Answer-*Inhibition* - Intermediate
product of metabolic pathway allosterically inhibits an enzyme that catalyzes an earlier
reaction in the same pathway.
*Activation* - Activation of an enzyme by an intermediate appearing upstream in a
metabolic pathway
-Helps keep reaction rates steady under normal conditions, but also allows reactions to
speed up or slow down when conditions change.
, Cellular respiration and the oxidation of glucose - Answer-Know the 4 stages: where
each occurs and what is happening
Fermentation - Answer-
Uptake, utilization, and storage of energy in carbohydrates, proteins, and fats - Answer-
glycolysis - Answer-"Splitting of sugar"
Metabolic pathway of ten reactions, each catalyzed by different cytostolic enzyme.
Each glucose molecule is broken down into 2 pyruvate, 2 NADH, 2 H+, 2 ATP.
glycogenesis - Answer-
glycogenolysis - Answer-
gluconeogenesis - Answer-
lipolysis - Answer-
lipogenesis - Answer-
beta oxidation - Answer-
proteolysis - Answer-
deamination - Answer-
transamination - Answer-
Absorptive state versus postabsorptive state - Answer-
What is happening in each and what the primary energy source for most body cells is -
Answer-
Which organ system controls the switch between the absorptive and post absorptive
state - Answer-
CH. 4 Passive versus active transport - Answer-
Driving forces acting on molecules: - Answer-
Chemical driving force - Answer-
Electrical driving force (only acts on ions) - Answer-