Unit 1 Cell Bio Questions

Which of the following are involved in forming the tertiary structure of proteins?

H bonds, hydrophobic interactions, ionic bonds

During oxidation of a fatty acid, the fatty acid is joined to the molecule _______ and is broken down by stepwise removal of _______-carbon units as part of the molecule _______, which can then enter the citric acid cycle to be metabolized.

coenzyme A, 2, Acetyl CoA

A mutation that causes a G-protein to lose its ability to hydrolyze bound GTP would be expected to have constitutively

active alpha subunits

Steroid hormones usually act via receptors that

bind to DNA

The GTP on the G protein that is linked to adenylyl cyclase is split to GDP and Pi

by the active alpha subunit

The region of a gene that binds to a PKA phosphorylated protein is a _______.

cAMP Response Element

When an element in one signaling pathway either stimulates or inhibits an element of a second pathway it is referred to as _______.

crosstalk

In glycolysis, the key control enzyme that is inhibited by excess ATP is

phosphofructokinase

CREB is activated by

phosphorylation by protein kinase A in the nucleus.

Mutated oncogenic Ras proteins usually

cleave GTP less rapidly than normal.

The acceptor of acyl groups from pyruvate is _______.

coenzyme A

The _______ produced by the electron transport chain drives a flow of these ions through a complex of proteins called _______ to produce ATP from ADP and Pi.

proton gradient, ATP synthase

A researcher generated a mutant SH2- containing protein such that it binds tyrosine and phosphotyrosine with equal affinity. As a result, MEK activity would be expected to

remain the same with receptor dimerization and autophosphorylation.

Sphingomyelin contains two hydrocarbon chains linked to

serine

Plants store glucose in the form of _______, and animals store glucose in the form of _______.

starch, glycogen

Cholera toxin inhibits the ability of the a subunit of Gs to split GTP. If you treated cells with cholera toxin, the resulting effect would be _______ of adenylyl cyclase.

stimulation

What is best described as an engineering approach to understanding and manipulating biological systems?

synthetic biology

Which phrase best defines systems biology?

the computational overlay of data from both genomic and proteomic experiments

MEK is a protein kinase that phosphorylates _______ residues.

threonine and tyrosine

In chloroplasts, the proton gradient that drives ATP production is established across the _______ membrane.

thylakoid

A collection of all the RNAs that are expressed at any given time in a cell are referred to as the

transcriptome

Organisms that evolved the ability to use H2O as a donor of electrons and hydrogen for the photosynthetic conversion of CO2 to organic compounds radically changed Earth by producing

O2

Fatty acids are broken down in a stepwise process, _______ carbon(s) at a time.

2

In anaerobic cells, the oxidation of glucose yields _______ molecules of ATP per molecule of glucose.

2

In aerobic cells, the complete oxidation of glucose via glycolysis and the citric acid cycle yields between _______ and _______ molecules of ATP per molecule of glucose, depending on how the electrons from NADH enter the mitochondria.

36-38

Remarkably, approximately _______% of the predicted human proteins are related to proteins in simpler sequenced eukaryotes, including yeast, Drosophila, and C. elegans.

40

The large-scale project called ENCODE used RNA-seq to characterize all RNAs in 147 human cell types. The surprise result from analysis of the data revealed that even though there is only 1% of the genome that encodes for protein, more than _______% of the genome is actually transcribed.

50

Why is it thought that regulatory elements occur in clusters?

Allows the interaction of multiple transcription factors

Stretches of sequenced nucleotides that code for polypeptides are recognized by the

absence of chain terminating codons

Which signal molecule diffuses through the plasma membrane to ultimately bind nuclear receptors and influence transcription?

estrogen

Sugars can cyclize if they contain _______ or more carbons.

five

The currently accepted model of membrane structure is called the _______ model.

fluid mosaic

The ATP and NADPH produced by photosynthesis are used to synthesize _______ from _______ and _______.

glucose, CO2, H2O

Amino acids are synthesized from intermediates in _______ and from the _______.

glycolysis, CAC

The use of antibodies to determine protein-protein interactions is known as _______.

immunoprecipitation

If the equilibrium constant for the reaction A -> B is 0.5, and the initial concentration of A is 30 mM and of B is 15 mM, then the reaction

is at equilibrium

Neurotransmitters act by binding to receptors that are

ligand-gated ion channels