Chapters 7-10 Flashcards
(83 cards)
What must happen to amino acids before they can be used in catabolic reactions?
a) deoxygenated
b) dehydrogenated
c) decarboxylated
d) deaminated
deaminated
In glycolysis, a major portion of the energy remains in the final product, which is called…
a) glyceraldehyde 3- phosphate
b) citrate
c) glusose
d) pyruvate
pyruvate
In the reaction catalyzed by aconitase, the conversion of citrate to isocitrate in inhibited by fluoroacetate. Fluoracetate is used as a pesticide. Why is this an effective pesticide?
a) inhibits citric acid cycle
b) inhibits pyruvate oxidation
c) inhibits ATP synthase
d) inhibits glycolysis
inhibits citric acid cycle
What stage of cellular respiration can occur in human cells with or without oxygen present?
a) citric acid cycle
b) electron transport
c) pyruvate oxidation
d) glycolysis
Glycolysis
What happens to the oxygen that is used in cellular respiration?
a) converts to acetyl-CoA
b) makes glucose
c) makes citric acid cycle intermediates
d) coverts to carbon dioxide
e) reduces to form water
reduces to form water
All of the reactions of cellular respiration that occurs after glycolysis takes place in what part of the eukaryotic cell?
a) the plasma membrane
b) the cytoplasm
c) the chloroplast
d) the nucleus
e) the mitochondria
the mitochondria
How and where is ATP made in a eukaryotic cell?
ATP can be made by phosphorylation of ADP in the cytoplasm
What is the oxidized form of the most common electron carrier that is needed for both glycolysis and the citric acid cycle?
a) pyruvate
b) ATP
c) NAD+
d) FAD
e) acetyl-CoA
NAD+
When substrate level phosphorylation occurs, it means that:
a) ADP is converted into ATP by the addition of phosphate group
b) NAD+
c) ATP is converted into ADP plus a phosphate group
d) NADH is converted into NAD+ a protein
NAD+ is converted into NADH
During what step of glycolysis are two ATP molecules required?
a) acetyl-CoA formation
b) oxidation
c) glucose priming
d) pyruvate formation
e) cleavage and rearrangement
glucose priming
What is the function of a protein kinase?
a) phosphorylate GDP to generate GTP
b) to cleave membrane phospholipids
c) remove phosphate groups from proteins
d) add phosphate groups onto proteins
add phosphate groups onto proteins
In response to injury, cell fragments called plateled get activated to reduce clotting. Activated platelets release factor that can in turn bind to special membrane receptors on nearby cells. What type of signaling would this be considered?
a) autocrine
b) endocrine
c) direct contact
d) synaptic
e) paracrine
paracrine
You have identified a novel cytoplasmic protein. Through sequence analysis you are able to identify the presence of a number of serine/threonine phosphorylation motifs. Based on these data, you hypothesize that this protein may be a substrate for what kind of enzyme?
a) phospholipase
b) receptor tyrosine kinase
c) G protein-coupled receptor
d) tyrosine phosphatase
e) protein kinase
protein kinase
You have identified a molecule, molecule X, that can bind to the ATP binding site of a specific protein kinase, and prevent ATP binding. You are conducting a kinase assay using this protein kinase and a known substrate of this kinase, and have set up the reaction using the proper conditions and cofactors to allow for optimal protein kinase activity. If you add molecule X to the reaction, what do you predict will be the outcome?
a) less phosphorylation of the substrate will be seen in the presence of molecule X
b) more phosphorylation of the substrate will be seen in the presence of molecule X
c) the substrate will be phosphorylated normally in the presence of molecule X
Less phosphorylation of the substrate will be seen in the presence of molecule X
What enzyme phosphorylates MAP kinase kinase?
a) MAP kinase kinase
b) MAP kinase kinase kinase
c) MAP kinase
d) MAP phosphatase
MAP kinase kinase kinase
G protein-coupled receptors are the largest family of cell surface receptors. Each receptor passes through the plasma membrane how many times?
a) once
b) three times
c) seven times
d) five times
seven times
Some enzymatic receptors and most G protein-coupled receptors transmit the signal into the cytoplasm by utilizing other substances within the cytoplasm that are referred to as…
a) second messengers
b) intracellular receptors
c) first messengers
d) genes
second messengers
What is similar about G protein-coupled receptors and receptor tyrosine kinases?
a) both are enzymes
b) both are activated by autophosphorylation
c) both are directly bound to G proteins
d) both can activate phospholipase C
both can activate phospholipase C
The function of adenylyl cyclase is to…
a) stimulate the release of calcium from the endoplasmic reticulum
b) catalyze the conversion of ATP to cAMP
c) cleave PIP2 into DAG and IP3
d) directly activate protein kinase A
catalyze the conversion of ATP to cAMP
Growth of new blood vessels is stimulated by vascular endothelial growth factor. This ligand binds to the VEGF receptor, which leads to the dimerization and autophosphorylation of this receptor on cytoplasmic tyrosines. What type of receptor is the VEGF receptor?
a) enzymatic receptor
b) G protein-coupled receptor
c) steroid hormone receptor
d) channel-linked receptor
enzymatic receptor
Describe how phosphorglation can affect protein function.
Phosphorglation controls the protein function through the addition of phosphate groups.
Contrast the different types of receptors.
There are three different types of receptors: channel-linked, enzymatic, and G protein-coupled. Channel-linked receptors allows the passage of ions to bind many neurotransmitters have the same basic structure. Enzymatic receptors is where many cell-surface receptors that pretend to be enzymes or they are directly linked to them. It happens when a single molecule binds to a receptor which activates enzymes that add phosphate groups to proteins. G protein-coupled receptors is when cell-surface receptors indirectly act on enzymes or ion channels that binds the nucleotide guanosine triphosphate which is inserted in between receptors and enzymes.
Compare the function of RTKs to steroid hormone receptors.
Receptor Tyrosine Kinase influences cell cycle, cell migration, cell metabolism, and cell proliferation where all cells are affected through receptor signals. It signals pathways can lead to cancers. Steroid hormone receptors create large class compounds that combine estrogen, cortisol, progesterone, and testosterone. They act as regulators for gene expressions.
Contrast signaling through GPCRs and RTKs.
GPCR is a receptor that couples with a G protein. The function is to operate the link for the receptor to be a signal receiver and a protein effector that produces cellular responses. An RTK is activated by signal passages and inactivated through desphosphorylation or internalization.
