Physiology Study Guide Exam 1, Bio 103 physio
Terms in this set (75)
physiology is the study of how organisms function
homeostasis and its relationship to physiology
Homeostasis is vital to living! The tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes.
the process of staying at your set equilibrium of what your body is naturally supposed to be at. Set point is what our body is always trying to get back to and stay at.
Set point and relationship to homestasis
an internal regulatory system for maintaining a relatively stable physiological condition in the face of changing external circumstances, as body temperature in a varying climate.
Levels of organization...cells, tissues, organs..etc
cells, tissues, organs (one or more tissues working together), organ system( one or more organs working together working toward the same function), organism
4 Cell/tissue types and functions
Epithelial Tissue secretion, absorption and protection. Know different types i.e squamous, cuboidal, columnar etc "barrier"
Connective Tissue: loose, dense, blood, bone, cartilage and adipose "connects and anchors"
Nervous Tissue and neurons (related to CNS brain and spinal cord)
Neuron is a cell of the nervous system that is specialized to initiate, integrate and conduct electrical signals. Packaged together to create a nerve.
Have cardiac muscle, skeletal muscle and smooth (skeletal = voluntary)
Body fluid compartments
intracellular fluid vs extracellular fluid
intracellular being inside and extracellular on outside
cytosol is the fluid between organelles vs cytoplasm fluid that surrounds everything but the nucleus
Know and be able to explain the 3 types of feedback loops
Negative feedback- A process that is stopped by the body (shivering)
ex) body temp, blood sugar (insulin)
Positive feedback- A process that is continued by the body to reach a certain point (childbirth, orgasm)
- ex) blood clotting
Define and understand what a reflex is
involuntary response to stimulus
Know the differences between a hormone and neurotransmitter
hormone= Chemical regulator out of the endocrine glands that travels through the blood stream
Neurotransmitters are the chemicals which allow the transmission of signals from one neuron to the next across synapses
Biological rhythms (NORMAL Rhythms undergoing change)
Body functions are rhythmical changes
circadian rhythm a 24 hour cycle
waking and sleeping
enable homeostatic mechanisms to be activated at time change will likely occur. Feedback loops will bring these levels back to "normal"
Dynamic constancy (definition is in notes) A given variable that may change over a short period but is relatively constant and stable over time
Know the difference between protons, neutrons, and electrons
protons= positive charge
neutrons= neutral charge
What determines an atoms identity?
the number of protons it has
What is an ion? Cation? Anion?
ion=a molecule that has either a positive or a negative charge (due to the loss or gaining of one or more electrons)
cation= positive net charge
anion= negative net charge
What are the four chemical bonds?
ionic bonds between 2 oppositely charged ions
hydrogen (weakest bond)
Be able to define and explain the four bonds
Covalent : 1 or more electrons are shared in the outer shell between 2 atoms. Strongest bond Polar: Hydrophilic, unequal sharing of electrons, has positive and negative charges
Nonpolar: Hydrophobic, electrons equally shared, no net charge, found in lipid bilayers
Ionic: 2 oppositely attracted ions, strongly attracted, complete share!!!, hydrophilic ex) Na+ Cl - makes salt
Hydrogen: Any bond that is partnered with a hydrogen ion, weakest, helps determine shape and function, hydrophilic, no sharing or donation just an attraction
Hydrophilic vs hydrophobic
hydrophilic water loving
hydrophobic water fearing
What is an amphipathic molecule? Give an example...hint...makes up cell membrane.
Pertains to a molecule containing both polar (water-soluble) and nonpolar (not water-soluble) portions in its structure. (2) Of, or relating to, a molecule having hydrophobic and hydrophilic regions.
ex: phospholipid bilayer
What does pH measure?
The amount of H+ in a solution.
Acid vs Base
pH scale is from 0-14 closer to zero end is acidic, 7 is neutral, closer to 14 is considered basic
- acids increase the concentration of H+
-bases decrease concentration
Know the classes of organic molecules (macromolecules)
Carbs → monosaccharides (ex: glucose), disaccharide (ex: sucrose), polysaccharide (ex: glycogen) aka storage
Lipids → steroids 4 carbon bonds, subunit of lipid are fatty acids has hydrogen and carbon and one carboxyl group at the end, phospholipid (has phosphate in it) triglyceride
unsaturated has a break
Protein → Amino acids, primary (one single peptide chain), secondary (folds on itself), tertiary (3d structure multiple attractions), quaternary bunch of 3d structures (subunit of amino acid)
Nucleic Acid → Nucleotides made from sugar phosphorus nitrogenous base (act codon part)
DNA and RNA
-Know all subcategories...EX: Carbs- monosaccharide, disaccharide, polysaccharide...etc
Thymine replaces uracil (on test*) RNA
Protein- Amino Acid
Lipid- fatty acid
Nucleic Acid- nucleotides
Know and define a plasma membrane
Regulation between substances in and out of the cells between organelles and cytosol. Barrier to polar molecules not nonpolar
-Know 4 functions
of the plasma membrane.
The four main functions of the plasma membrane include identification, communication, regulation of solute exchange through the membrane, and isolation of the cytoplasm from the external environment.
What lipid makes up the plasma membrane?
lipid bilayer is a double layer membrane formed from phospholipids
What is another name for the cell membrane?
-integral transmembrane they go into the membrane and are lipid soluble
-peripheral only touch heads water soluble (no fat)
-Integral: Plasma membrane attaches to a specific protein. Associated with nonpolar side, membrane lipid
-Tight Junctions: No space in between, 2 plasma membranes, weak but permeable, prevent movement (EX- bladder lining)
-Gap Junctions: Protein channels
-Desmosomes: "dense plaques", separated, anchors cadherins (proteins that extend from cell to extracellular space), firm and strong, (EX- streching skin)
Organelles and function
-Mitochrondia: Energy for ATP (Power House)
- Nucleus- Stores DNA, place for transcription
- Rough ER- Has ribosomes attached, Protein synthesis- anything destined to become membrane bound or proteins secreted made here
- Smooth ER: Lighting cells- lipids, steroids, testes, skeletal, smooth, cardiac muscle cells: stores calcium
Ribosomes: Important in protein synthesis- into amino acids
Golgi: Modifications, come from rough ER •
Deoxyribonucleotides: Used in DNA - A, G, T, C
Ribonucleotides: Used in RNA- A, G, U, C
How does ATP get broken down into ADP + P?
-ATP what we're breaking down to create energy
Adenosine Triphosphate (broken down by hydrolysis)
Using water to break large molecules into smaller molecules
-Start with APPP after hydrolysis it is converted to APP instead of tri being 3 is di meaning 2 so = ADP+P
ATPASE pump has byproduct of water*
Enzymes and their function...how do they speed up a reaction?
It is a protein catalyst. Lower the activation energy and make biological reactions proceed at a higher reaction rate.
-transcription: DNA makes RNA
-translation: RNA makes a protein
-what is a triplet/codon
Triplets are three sequences of amino acids that code for a certain protein, 64 in total, 61 codons.
codons are the remaining 3 that are the period at the end of the sentence
-exon: codes that make a protein (execute job)
-intron: do not code
-spliceosomes: cuts out the introns
tRNA vs mRNA
DNA is transferred to mRNA (modified)(all modification happens in the nucleus), then goes into a ribosome where the tRNA (triplet, codes 3), moves down and a new one comes in. Last one has a chain of amino acids.
Structure and Function of a gene
A gene is a region of DNA that encodes function. A chromosome consists of a long strand of DNA containing many genes. A human chromosome can have up to 500 million base pairs of DNA with thousands of genes. A gene is a locus (or region) of DNA which is made up of nucleotides and is the molecular unit of heredity
Specificity vs Affinity
Affinity: How strong the bond is, and how likely it is to bond
Specificity: (specific Shape) Ability of a protein binding site to bind specific ligands, can bond to only one or many
Metabolic Pathways (know and be able to explain)
-Glycolysis (happens outside so occurs in cytoplasm)
-1st phase considered "investment"
-2nd phase considered "energy pay off"
-4 ATP is end result
Krebs cycle (aka the citric acid cycle)
-The sequence of reactions by which most living cells generate energy during the process of aerobic respiration. It takes place in the mitochondria, consuming oxygen, producing carbon dioxide and water as waste products, and converting ADP to energy-rich ATP.
-Two molecules of carbon dioxide are given off
-One molecule of ATP is formed
-Three molecules of NAD+ are combined with hydrogen (NAD+ → NADH)
-One molecule of FAD combines with hydrogen (FAD → FADH2)
the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing energy which is used to reform ATP. In most eukaryotes, this takes place inside mitochondria. (Makes the most ATP)
Diffusion and net flux
-Net flux represents the amount of substance moved in or out of the cell.
-Diffusion through random thermal motion
-Simple diffusion ONLY RTM (heat created movement and collisions leading to diffusion of molecules from high to low)
-Facilitated diffusion Has BOTH RTM and protein channels
ex: glucose facilitated diffusion
Net diffusion of water across a membrane. Aquaporin (channels) expression and insertion into the membrane varies among cell types.
-primary: uses ATP directly (helps maintain membrane potential)
-secondary: uses electrochemical gradient across membrane
What transport system does glucose use?
Positive on outside, negative on inside
caused by ions going back and forth more positive on the outside and the inside is more negative
At rest what is the normal membrane potential...negative or positive ?
Ion channel Regulation
ligand gated and voltage (uses channels to diffuse)
Hypotonic vs hypertonic vs isotonic
-hypotonic= h2o flows into the cell and the cell gets bigger
-hypertonic= h2o flows out of the cell and the cell shrinks
-isotonic= even amount of h2o flowing in and out of the cell "normal cell"
Endocytosis vs Exocytosis (know all types)
Endocytosis (3 types) Endo "inside" have pockets called vesicles
1.pinocytosis- (cell drinking) certain solute
2.Phagocytosis- (cell eating) big chunks of bacteria
3.Receptor-mediated endocytosis- a process by which cells absorb metabolites, hormones, other proteins - and in some cases viruses
exocytosis= taking something out of the cell "exo" means outside
Receptor (aka protein)
A molecular structure or site on the surface or interior of a cell that binds with substances such as hormones, antigens, drugs, or neurotransmitters
a molecule or ion that binds to a protein (aka receptor)
Specificity and affinity
-specificity= specific shape complementary to the receptor
-affinity=The strength of the attraction between the ligand and a receptor
Understand saturation and competition
-saturation=the fraction of total binding sites that are occupied
-competition= presence of multiple ligands able to bind the same binding site (ex: methadone competes with heroin for the binding site) WILL BE A QUESTION ON THE TEST!
-antagonist= blocks the action of a chemical messenger
-agonist= activates receptor and triggers the cell's response
First messengers vs second messengers
-1st messenger= ligand
-2nd messenger= cAMP
G-protein coupled receptors (know and explain)
-The G protein can change the membrane potential (keep in mind)
-Once ligand is placed into the Receptor it activates G protein--alpha binds to adenylyl cyclase
-There are three molecules alpha gamma and beta (alpha is the important one)
-Alpha is the molecule that activates/attaches the adenylyl cyclase
-ATP is the converted into cAMP (second messenger) turns protein kinase from inactive to active
-Second messenger is in the cytoplasm (intercellular fluid) *** WILL BE ON TEST
-Protein kinase phosphorylates all proteins and activates a cell response
Pathways initiated by lipid soluble messengers and water soluble messengers
Lipid soluble messengers have intracellular receptors and can diffuse through membrane
Water soluble bind to receptors on plasma membrane and activated by second messengers
Which of the following is not a chemical bond?
Which of the following is a hydrophilic bond?
What is an example of a amphipathic molecule?
What uses DNA to make RNA?
It comes from nucleus and travels by synapse
What is the monomer for carbohydrates?
Membrane Junction that consists of protein channels with linking cytosol
What is hydrolysis
breaking of molecules with water
Moving from high to low concentration using only random thermal motion
What are the types of endocytosis
phagocytosis, pinocytosis, receptor mediated
What cycle gives the most ATP?
What is a ligand?
A molecule or ion that binds to a protein
What is a hypotonic solution?
Solutes that have a lower concentration
What is the first messenger in the G-protein coupled receptor?
Ligand 1st messenger
Where does the second messenger occur?
In the cytoplasm
the second messenger
Where is the second messenger found in the
G-protein coupled receptor?
What is an example of competition?
What regulates membrane potential?
sodium potassium ATPase pump
What cuts out the introns?
Which is NOT typically a step in the cAMP second-messenger system?
A. A first messenger binds to a transmembrane receptor.
B. There is dissociation of G-protein subunits.
C. An activated G-protein subunit phosphorylates cAMP dependent protein kinase.
D. Adenylyl cyclase converts ATP into cAMP
E. Active cAMP dependent protein kinase phosphorylates cell proteins.
Two cell types having the same type of receptor for chemical messenger will always respond to that messenger in the same way.