Physiology of Cells (Chapter 4)
what is a uniporter?
a carrier pump in the body that transports only one type of molecule at a time
what does allosteric relate to?
a change in 3D shape
what is end product inhibition?
a chemical product at the end of a metabolic pathway that binds to the allosteric of one or more enzymes along the pathway that produced it and inhibits the synthesis of more product
what does a sequence of three base pairs in a DNA molecule form?
a codon
what are hydrolyzing enzymes?
a group of digestive enzymes
what is a polymer?
a large molecule made up of many smaller molecules joined together in a sequence
what is the lock and key idea?
a model that describes the action of enzymes
what is the allosteric effector?
a molecule or other agent that alters enzyme function by changing its shape
what is a hypotonic solution?
a solution that causes cells to shrink
what is a hypertonic solution?
a solution where water enters the cell
what is an isotonic solution?
a solution with a net diffusion of zero
what is mRNA?
a stand of nucleotides that serve as a working copy of one protein coding gene
what is tRNA?
a strand of nucleotides with an anticodon on one side and an amino acid binding site on the other
what is a substrate?
a substance on which an enzyme acts
what is the movement that requires cell energy?
active transport
what is the uphill movement of a substance through a living ell membrane called?
active transport
what kind of transport is endocytosis?
active transport
what kind of transport is the ion pump an example of?
active transport
what do phosphorylating enzymes do?
add or remove phosphate groups
what are the two base pairs in the DNA molecular structure?
adenine and thymine, cytosine and guanine
what are the base pairs that take place in the mRNA strand?
adenine and uracil, cytosine and guanine
what is a process that requires oxygen called?
aerobic
how are hydrolyzing enzymes named?
after the substrate acted on
how does an actively transported substance move?
against its concentration gradient
where does diffusion occur?
along the concentration gradient
what is an effector?
an agent that accomplishes something
what is a genome?
an individual's entire set of DNA
what is the opposite of catabolism?
anabolism
is glycolysis aerobic or anaerobic?
anaerobic
what is a process that requires no oxygen called?
anaerobic
in which stage of mitosis do chromosomes move to opposite ends of the cells along the spindle fibers?
anaphase
true/false? DNA contains ribose sugar.
false
true/false? RNA molecules are larger than DNA molecules.
false
true/false? facilitated diffusion is a metabolically expensive process.
false
true/false? gamete is referring to a point of attachment of newly replicated DNA molecules.
false
true/false? glycolysis is aerobic.
false
true/false? hyperplasia refers to an increase in cell size
false
true/false? hypertrophy refers to an increase in cell number
false
true/false? one similarity between DNA and RNA is that they both are shaped as a double helix.
false
true/false? osmosis is a form of filtration that results in the separation of small and large solute particles.
false
true/false? the lock and key model is used to describe how DNA base pairs align.
false
true/false? the number of chromosomes are halved during meiosis II.
false
true/false? viruses do not contain DNa or RNA.
false
what is a specialized example of diffusion?
filtration
what is the movement that always occurs down a hydrostatic pressure gradient?
filtration
how do molecules move during diffusion?
from an area of high concentration to an area of low concentration
what are enzymes classified as?
functional proteins
what are sex cells called?
gametes
what is the formula for cellular respiration?
glucose + oxygen = water + carbon dioxide
what are the three processes of catabolism?
glycolysis, Krebs cycle, electron transport cycle
the concentration BLANK measures the difference from one area to another
gradient
what does the cell do to prepare for mitosis in G2 phase?
grows rapidly
what do membrane channels or carriers do?
help molecules diffuse across cell membranes
what are enzymes that add water to a molecule without splitting is called?
hydrases
what are all digestive enzymes classified as?
hydrolases
what is another name for hydrolyzing enzymes?
hydrolases
what is the force of a fluid pushing against the surface called?
hydrostatic pressure
if the solution is hypotonic, what is the cell?
hypertonic
what is a saline solution that contains a higher concentration of salt than living red blood cells be called?
hypertonic
a red blood cell becomes engorged with water and will eventually lyse, releasing hemoglobin into the solution. the solution is BLANK to the red blood cell?
hypotonic
if the solution is hypertonic what is the cell?
hypotonic
where are GLUT importers found?
in cells that passively move glucose from blood to plasma cells
where does meiosis occur?
in primitive sex cells during the process of becoming mature sex cells
where is the site of translation?
in the cytoplasm
where does glycolysis take place?
in the cytosol of the cell but in no particular organelle
where does the Krebs cycle occur?
in the inner chamber of the mitochondrion
where does the electron transport system occur?
in the matrix of the mitochondrion
where does transcription take place?
in the nucleus
where is the site of transcription?
in the nucleus
where do sodium-potassium pumps operate?
in the plasma membrane of all human cells
what are enzymes synthesized as?
inactive proenzymes
what are the three steps of translation?
initiation, elongation, termination
how do sodium-potassium pumps transport K ions?
into the cells
how are enzymes classified?
intracellular or extracellular
what is exocytosis?
process by which large molecules can leave the cell even through they are too large to move through the plasma membrane
what is endocytosis?
process that allows extracellular material to enter the cell without actually passing through the plasma membrane
what are the 4 phases of mitosis?
prophase, metaphase, anaphase, telophase
what is the correct order of the phases of mitosis?
prophase, metaphase, anaphase, telophase
what does the cytoskeleton do to the plasma membrane during endocytosis?
pulls part of the membrane inward
what is the pre-process of the Krebs cycle?
pyruvic acid is converted to acetyl coenzyme that produces carbon dioxide
what does receptor mediated do?
receptors in the plasma membrane bind to specific molecules in the extracellular fluid
what is the general function of enzymes?
regulate cell functions by regulating metabolic pathway reactions
which organelle is the site of translation?
ribosome
is RNA a single or double strand?
single
who is the Krebs cycle named after?
sir Hans Krebs
skip
skip
how do small hydrophilic molecules diffuse?
slightly
what are kinases?
substances that convert proenzymes to active enzymes
what is the type of RNA that has an anticodon and binds to a base pair specific amino acid?
tRNA
what is the structure of most enzymes?
tertiary or quaternary proteins of complex shape
what does end product inhibition prevent?
the accumulation of an extreme amount of metabolic product
what happens during g2 phase during interphase?
the cell continues to grow until it is to its max size
what happens to the cell during interphase?
the cell grows
what does hypotonic mean?
the cell or solution (depending on what it is referring to) has less particles in it
what does hypertonic mean?
the cell or solution (depending on what it is referring to) has more particles in it
what is mitosis?
the cell organizes replicated DNA into two identical sets
what does isotonic mean?
the concentrations inside and outside of the cell are the same (space between particles)
what grows during G1 and G2 phases?
the cytoplasm
what does tertiary mean?
the final shape that the proteins assumes
what does the structure of an enzymes determine
the function
what is the result of fertilization during meiosis?
the fusion of two gametes to form a zygote
what is active transport?
the movement of a substance into or out of a living cell requiring the use of cellular energy
what is simple diffusion?
the movement of particles through the phospholipid bilayer or channels down a concentration gradient
what happens during meiosis I?
the number of chromosomes is halved but chromatin paris remain together
what happens during cytokinesis?
the plasma membrane and cytoplasm is split into two
what is the active site?
the portion of the enzyme that chemically fits the substrate
what is catabolism/cellular respiration?
the process by which chemical energy is released and captured in the form of ATP
what is translation?
the process in which cellular ribosome produces proteins
what is suffix -ase used with when naming an enzyme?
the root name of the substance and the word that describes the kind of chemical reaction catalyzed
what does quaternary mean?
the structure formed by several protein molecules
what is transcription?
the synthesis of any RNA molecule as a portion of the DNA coded is copied or transcribed
what is anabolism?
the synthesis of complex molecules in living organisms from simple compounds
what kind of RNA does transcription synthesize?
the synthesis of mRNA
what is a diploid?
the total of 46 chromosomes per cell
why do enzymes have to continually be synthesized?
they are continually destroyed
what do catalyst do?
they increase the rate of chemical reactions within cells
what are the two fundamental properties that enzymes are characterized by?
they increase the rate of chemical reactions without being consumed of permanently altered by the reactions and they increase reaction rates without altering the chemical equilibrium between reactants and products
what happens when vesicles fuse with the plasma membrane?
they release contents outside of the cell
where does the water want to move?
to where there is a higher concentration or more particles
what is the process that occurs when the double strands of a DNA segment separate and RNA nucleotides pair with the DNA nucleotides?
transcription
what is the process involving the movement of mRNA with respect to the ribosome?
translation
what is the synthesis of proteins by ribosomes using information coded in the mRNA molecule called?
translation
what are antiporters?
transporters that move 2 different types of molecules in opposite directions at the same time
what does the plasma membrane do to extraceullar material during endocytosis?
traps it
true or false the deoxyribonucleic molecule is a giant compared to other molecules?
true
true/false? DNA has obligatory base pairing.
true
true/false? DNA has phosphate groups.
true
true/false? DNA is a double helix shape.
true
true/false? RNA contains uracil and not thymine.
true
true/false? RNA has obligatory base pairs of adenine-uracil and guanine-cytosine.
true
true/false? RNA is single stranded.
true
true/false? a blood disease caused by the production of abnormal hemoglobin is known as sickle-cell anemia.
true
true/false? cystic fibrosis is a condition in which chloride ion pumps in the plasma membrane are missing
true
true/false? diabetes mellitus is a disorder of cell membrane receptors.
true
true/false? genetic disorders are mutations in a cell's genetic code.
true
true/false? normal mitosis results in daughter cells that are genetically identical to the parent cell.
true
true/false? protein anabolism is a major cellular activity.
true
true/false? solutes are particles dissolved in a solvent.
true
true/false? telophase is the completion phase of mitosis.
true
true/false? the citric acid cycle is also known as the Krebs Cycle.
true
true/false? the portion of an enzyme molecule that chemically fits the substrate molecule is referred to as the active site.
true
true/false? the processes that comprise cellular respiration are glycolysis, the citric acid cycle, and the electron transport system.
true
true/false? the sodium-potassium pump is an example of an active transport process.
true
true/false? cellular secretion can be achieved by exocytosis.
trye
what can the activation or inactivation of enzymes do?
turn the entire pathway on or off
how does transport by vesicles differ from transport by pumps?
vesicles allow substances to enter or leave the cell without passing through the plasma membrane
what are 2 examples of a small hydrophilic molecules?
water and urea
what is osmotic presure?
water pressure that develops as a result of osmosis
when does equilibrium occur?
when both solutions have equal cncetration
when is a vesicle formed?
when extended edges of membrane fuse together
when does thymine change to uracil?
when writing the mRNA strand in the sequence
what is an example of a cell that uses phagocytosis?
white blood cells
what is the female sex chromosome?
xx
what is the male sex chromosome?
xy
are enzymes specific in their action?
yes
do enzymes catalyze a reaction in both directions?
yes
is DNA a polymer?
yes
is the carrier-mediated type of facilitated diffusion reversible?
yes
are most enzymes intracellular?
yes except digestive enzymes
what is another name for antiporters?
countertransport
what do water molecules do?
diffuse or osmose
what is an example of a passive process?
diffusion
what is passive transport?
diffusion of substances across a membrane
what are three processes of passive transport?
diffusion, filtration, osmosis
how do hydrophobic molecules diffuse?
directly
how does the carrier-mediated type of facilitated diffusion transport substances?
down the concentration gradient
how do ions move as they pass through channels?
down their concentration gradient
when do spindle fibers disappear during mitosis?
during telophase
is equilibrium static or dynamic?
dynamic
what happens during anaphase?
each centromere splits and sister chromatids move to opposite poles
what are the two processes of transport by vesicles?
endocytosis and exocytosis
what does pinocytosis do?
engulfs liquids or dissolved particles called cell drinking
what does phagocytosis do?
engulfs whole food particles called cell eating
what process traps intracellular material and brings it into the cell?
enocytosis
what is a chemical catalyst called?
enzyme
what can water do but solutes cannot do?
equilibrate its concentration on both sides of the membrane
what is another name for a tumor?
neoplasm
what happens during telophase?
new chromosomes start elongating, DNA molecules start uncoiling, the nuclear envelope forms to enclose each new set of chromosomes
what is produces during G1 and G2 phases?
new organelles and the plasma membrane
is energy used during diffusion?
no
what is a cofactor?
nonprotein part of the enzymes
what do enzymes allow reactions to do?
occur at the low level of free energy available at normal human body temperature
the diffusion of water through a selectively permeable membrane in the presence of at least one impermeant solute is called what?
osmosis
what involves the movement of solutes across a selectively permeable membrane by the process of diffusion called?
osmosis
what is the diffusion of water called?
osmosis
how do sodium-potassium pumps transport Na ions?
out of the cells
what are 2 examples of hydrophobic molecules?
oxygen and carbon dioxide
what kind of transport is diffusion?
passive transport
what is osmosis?
passive transport of water across a membrane
what do molecules that pass through a membrane do to the membrane?
permeate it
what is the trapping of bacteria by specialized white blood cells an example of?
phagocytosis
what are the three types of endocytosis?
phagocytosis, pinocytosis and receptor mediated
what are phosphorylating enzymes known as?
phosphorylases or phosphatases
what is not a process of passive transport?
pinocytosis
what are protein tunnels?
pores where molecules can pass
a change in volume means a change is what?
pressure
what suffix is used when naming an enzyme?
-ase
what is the haploid number of chromosomes?
23
what is the diploid number of chromosomes?
46
what does the electron transport system produce?
ATP
what is the energy required for active transport processes called?
ATP
what happens during s phase of interphase
DNA molecules are replicated
what is the process of transcription?
DNA unzips, RNA nucleotides attach to exposed bases, nucleotides align and bind to form mRNA
what happens during the g1 phase of interphase?
G1- new organelles are made and everything is ready for DNA synthesis
what is the shortest sub phase during interphase?
G2 phase
what enzyme controls the formation of mRNA?
RNA polymerase
what does the membrane carrier do during carrier-mediated facilitated diffusion?
attracts a solute to a binding, changes shape, then releases the solute on the other side of the membrane
what is end-product inhibition a type of?
automatic feedback mechanism
why are all digestive enzymes classified as hydrolases?
because they catalyze the hydrolysis of food molecules
what is another name for enzymes?
biological catalysts
what does glycolysis mean?
breaking glucose
how are pump mechanisms powered?
by cellular energy
what are enzymes that add or remove carbon dioxide called?
carboxylases or decarboxylases
what does tRNA do?
carries an amino acid to a specific codon of mRNA at a ribose during translation
what are enzymes that cause essential chemical reactions called?
catalysts
what are most biological reactions?
catalyzed proteins
what is cytokinesis?
cell movement
what does active pumping allow?
cells to move certain ions or other water-soluble particles to specific areas
what is the electron transport system essential for?
cellular respiration
what happens during prophase?
centrioles move to opposite poles of the cell and spindle fibers appear and begin to orient between opposing poles
what are the two types of facilitated diffusion?
channel-mediated and carrier-mediated
what happens during meiosis II?
chromatids split apart
what happens during metaphase?
chromosomes align across the equator of the spindle fibers at the centromere
what is another name for the Krebs cycle?
citric acid cycle
what is a coenzyme?
cofactor that is an organic molecule
what are uracil-adenine an example of?
complimentary base pairing
what is the movement of substances from a region of high concentration to a region of low concentration called?
concentration gradient
what is another name for symporters?
cotransports
what is the result of the sodium-potassium pump?
it maintains a lower Na concentration in intracellular fluid than in the surrounding extracellular fluid
what does the potential osmotic pressure do?
it predicts actual osmotic pressure
what are 3 examples of hydrolyzing enzymes?
lipase, sucrase, maltase
what is the type of RNA that carries info in groups of three nucleotides called codons, each of which codes for a specific amino acid?
mRNA
what is the process of sex cell reproduction called?
meiosis
what are various transport proteins also known as?
membrane channels or carriers
how do pumps transport substances?
membrane pumps use cellular energy to move molecules uphill through a cell membrane
what are selectively permeable membranes?
membranes that are only permeable to some molecules
what is the sum of chemical reactions in a cell?
metabolism
what is DNA a polymer of?
millions of pairs of nucleotides
what is the process of cell reproduction called?
mitosis
what happens to molecules during exocytosis?
molecules are enclosed in a vesicle by the Golgi apparatus and the vesicles are pulled out to the plasma membrane by the cytoskeleton
what are symporters?
move 2 or more types of molecules in the same direction through a membrane
what does uphill mean in active transport?
moving a substance from an area of low concentration to high concentration
what are enzymes that rearrange atoms with a molecule called?
mutases or isomerases
