Flashcards in MCAT Biology Flashcards 3 Deck (70):
Gases move from areas of ____ partial pressure to areas of ______ partial pressure.
Higher to LOWER
circular smooth muscle
The inner layer of smooth muscle in the wall of the digestive tract. When this, the tube diameter is reduced. Certain areas of the circular muscle are thickened to act as valves (sphincters).
Voltage Gated Sodium Channels
Big player in depolarization since it allows Na+ to flow into the cell.
Common bile duct
The duct that carries bile from the gallbladder and liver to the small intestine (duodenum).
A region at the head of a sperm cell that contains digestive enzyems which, when released during the acrosome reaction, can facilitate penetration of the corona radiata of the egg, and subsequently, fertilization
Anabolic processes ______ NADH, NADPH, and FADH2 and they _______ energy.
OXIDiZE, and require energy to continue.
How many ATP molecules do each NADH and FADH2 produce?
NADH=2-3 ATP, FADH2= 2ATP
Nucleus (Nervous system)
A cluster of cell bodies WITH IN the CNS
Seminal Fluid is secreted by three glands: _____, ____, and the _____
Seminal vesicles, the prostate gland, and the Bulbourethral glands.
What are B lymphocyte plasma cells?
They make and release antibodies which induce antigen phagocytosis
The ovum consists of two layers of cells: The outer one is the ________ and the inner layer is the _______
Corona Radiata, and the Zona Pellucda
What do we call cells that produce an Rh factor? Do they produce an antibody?
Rh+, they produce no antibody
What are the two main premises that Darwin argued
No two members of a species are exactly alike even if they have the same parents AND Some variations are advantages, giving the organism the chance to branch out into new environments and to enlarge its numbers
What do we call cells that do not have an Rh factor?
Rh-, lack antigen and produce an antibody
Six carbon carbohydrate
enzyme that phosphorylates somethings
function as enzymes-pepsinhormones-insulinmembrane pumps and channels- Na/K pumptransporter and storagereceptors
triglyceridesfats and oilsconstructed from glycerol that is attached to 3 fatty acids. FUNCTION IS TO STORE METABOLIC ENERGYPROVIDE THERMAL INSULATION AND PADDING
conformation disruptedlost most of its secondary, tertiary and quaternary structurevery often, when denaturing agent removed, protein spontaneously refolds to original structure
Proteins containing nonproteinaceous components
four ringed structures, contain hormones Vitamin D and cholesterolREGULATE METABOLIC ACTIVITIES
Common nitrogenous bases in nucleotides
modification of enzyme config. resulting from the binding of an activator or inhibitor at a specific binding site on the enzyme
solvent in which chemical reactions take place.80 percent of cell's mass is due to water
Two types of proteins
Globular and Structural
mixture of proteins and carbohydrates. major component of extracellular matrix
Denaturing Agent- Urea
Force Disrupted- Hydrogen Bonds
Water molecules surround a hydrophilic molecule.
Major function of steroids ***
regulate metabolic activities
bind ccovalently to enzymes and disrupt their function. (a few bind nonconvalantly)ex: penicillin which binds to bacterial enzyme that assists in the manufacturing of peptidoglycan cell walls
as relative conc. of substrate increases, rate of rxn increases but to a lesser & lesser degree until Vmax achieved.Vmax is proportional to enzyme conc. as individual substrates must wait in line for an open substrate as more substrate is added
required for enzymes to reach optimal activity-non-protein compound...can be coenxzymes or metal ions
*Many coenzymes are often...
vitamins or their derivatives
Starch comes in two forms
amylose and amylopectin
Ring form of Glucose
it has two anomers
carbohydrates attached to 3 C glycerol and two fatty acids. also amphipathicFOUND IN ABUNDANCE IN THE MEMBRANCES OF MYELINATED CELLS COMPOSING THE HUMAN NERVOUS SYSTEM
Contribute to confirmation of protein. can be alpha helix or beta pleated sheets
Saturated Fatty Acids
possess only single carbon-carbon bonds
each amino acid in a polypeptide chain
made from long polymersmaintain and add strength to cellular and matrix structure. ex. collagen
building blocks for most complex lipidslong chains of carbon that have carboxylic acid at one end
induces turns in the polypeptide that will disrupt both alpa helix and beta pleated sheet formation
10 amino acids
are essential, human cannot manufacture these have to be ingested directly
Minerals and their function
dissolved inorganic compounds inside and outside the cell-assist in tranpoting substance in and out of cell by creation of electrochemical gradients across membranesthey can combine and solidify to give strength to a matrix, such as hydroxyapatite in bondalso act as cofactors assiting enzyme or protein function
Reversible covalent modification
some enzymes are activated or deactivated by phosphorylation or the additin of some other modifier such as AMP. Hydrolyis almost always can removed modifier. Phosphorylation almost almost occurs in presence of protein kinase
*Basic structure of Carbs
C(H2O)also called sugars or saccharides
2 types of coenzyme
2 types:cosubstrates- reversibly bind to specific enzyme and transfer some chem. group to another substrate. It reverts to orginal form by another enzymatic rxn, which is what distinguishes it from normal substrates. ATP is an exampleProstheic group- remain covalently bound to enzyme throughout rxn
Unsaturated Fatty Acids
contain one or more carbon-carbon double bonds
Water can hydrogen bond and this allows it to stay at its liquid stage in cellular environment.
amino acids differ in side chains, often are the R group.side chain is also attached to alpha carbon
when two or more polypeptide chains bind together, form quaternary structure of the protein.
bind noncovalantly to an enzyme at a spot other than active site & change conformation of enzyme-commonly act on more than 1 enzyme-can NOT be overcome by substrate conc. increase-lower Vmax-do NOT lower enzymes affinity for substrate, thus Km remains the same
Major function of triglycerols ***
store metabolic energy, provide thermal insulation, and padding
*3 parts of nucletides
1) 5-C sugar2) Nitrogenous base3) phosphate group
Alpha glucose anomer
Hydroxyl group on the anomeric carbon- carbon # 1 and methoxy group- c # 6 are on opposite sides of the carbon ring.
Major function of some fatty acids (eicosanoids ***
serve as local hormones
**quarternary structure of proteins
2 or more polypeptide chains bind together and same 5 forces as tertiary
Denaturing Agent- salt or change in pH
Force Disrupted- Electrostatic Bonds
Animals can digest starch and glycogen but not
beta linkages of cellulose.
Positive cooperativity as related to allosteric regulation
phenomenon in which the first substrate changes the shape of an enzyme allowing other substrates to bind more easily
Where can glucose be absorbed against a conc. gradient?
certain epithelial tissues in digestive tract and proxiaml tubule of kidneyhow: 2ndary active transport down conc. gradient of Na
Given a complicated question regarding complicated chemicals, what does the "ase" imply? and why is it important?
enzyme, so know it contains nitrogen and subject to denaturization
Name 4 imp. nucleotides and their respective funct.
1) ATP- readily available energy2) cyclic amp- imp. component in many 2ndary messanger systems3 & 4) NADH & FADH2 - coenzymes in Krebs cycle
Nucleotides are composed of three components
1. five carbon sugar2. a nitrogenous base3. a phosphate group
Structure of fatty acids and how energy is released from them
long chains of carbons truncated at one end by a carboxylic acid (COOH)-energy liberated through oxidation of fatty acids->released large amounts of chemical energy for a cell
20 Common Acids are Split into 4 groups
Nonpolar R groupsPolar R groupsAcidic R groupsBasic R groups