final study guide for bio 94

This is a cell cycle histogram of normal cells (top) and cancer cells (bottom). The X axis is the amount of double-stranded DNA in each cell, the Y axis shows the number of cells. The P5 area of the CANCER graph represents:

Aneuploidy

In class, we discussed the adaptations of the grasshopper mouse to avoid pain from the Arizona bark scorpion's venom. The mouse has an altered response of voltage gated sodium channels to venom in the

Peripheral nervous system

Genome-wide association studies look at the genomes of a large number of people who vary in a particular complex trait like intelligence. The hope is that GWAS will help determine which genes are associated with the trait. This type of study is looking for:

Polygenic inheritance

In the population that this family comes from, would you expect the mutant alleles that contribute to this condition to be very rare, or pretty common?

Pretty common

When a protein is placed in an abnormally hot or acidic environment, it will still retain (does not lose) this level of structure:

Primary structure

Cells have a mutation that causes the tRNA that recognizes the codon UGC to be charged with Trp not Cys. Those cells would have

Proteins would have less cysteines than usual, and more Trp

This caffeine molecule has a structure most similar to:

Purine Nucleotide

Which of the following signaling types would be most immediately limited by a reduction of ATP in the cell?

RTKs

In 2022, researchers track new DNA strands by allowing cells to reproduce in the presence of a chemical like BrdU. An older method tracked DNA by allowing cells to reproduce in the presence of:

Radioactive phosphates

The antiviral drug molnupiravir is effective against SARS-CoV-2 but not against HIV or parvoviruses. Which is a possible location of action?

RdRP

Which of these does NOT involve RNA binding to DNA?

Regulation by microRNAs

Substrate level phosphorylation to generate ATP, during glycolysis and the citric acid cycle, can occur because

ATP and the other products are not the highest energy molecules in the reaction

In one extreme case, a single gene is thought to give rise to 38,000 different versions of the same protein. This could be an example of

Alternative splicing

Using Mendel's pea plants, let's cross a plant that is ggFfTT x GGffTt. Assuming these genes are each on separate chromosomes, what is the probability that the offspring will be heterozygous for all 3 traits?

1/4

Two genes, ry and e, have a recombination frequency of 33% in flies. Normal flies have red eyes, while ry/ry mutant flies have rosy deep pink eyes. Normal flies have a beige body, but e/e mutant flies have an ebony body. If you were doing a test cross to determine the recombination frequency between these genes, what would be the phenotypes of the first 1000 progeny?

165 rosy+beige, 165 red+ebony, 330 rosy+ebony, 330 red+beige

How many amino acids were linked together to make this polypeptide?

4

Which is NOT part of a promoter?

5' cap

Researchers are studying different mutations of the LDL receptor that cause familial hypercholesterolemia. This figure shows the number of mutations at each location for each receptor type.

Amino acids

Which of the following pairs are likely to form hydrogen bonds?

Ammonia (NH3) and water

Cholera is caused by a bacterial toxin binding to the cell membrane of the gut. The toxin binds to this molecule:

Amphipathic

What is one difference between inductive signaling proteins and master regulators in development?

Only one of these proteins is a transcription factor

Look at the elements found in chitin, which is part of the exoskeleton of insects: Which atom of the elements found in chitin has the most electrons?

Oxygen

The chemical Gboxin has been recently identified as a potential anti-cancer therapeutic drug. Gboxin inhibits the activity of ATP synthase in the inner mitochondrial membrane. In cells treated with Gboxin, what would you expect to see immediately:

A more acidic pH in the intermembrane mitochondrial space

Researchers are studying the effect of a drug, LMB, on the localization of a protein, alpha-TAT1. The drug LMB is diluted in ethanol. They look at the location of alpha-TAT1 by tagging it with the fluorescent protein GFP, then measuring what fraction of cells have the fluorescence in the nucleus. In this experiment, Ethanol is

A negative control

Some cells respond more slowly to a ligand binding to an RTK. Which would most likely cause this?

A plasma membrane with more saturated hydrocarbons

The nerve gas Sarin acts by inhibiting an enzyme called acetylcholinesterase, which breaks down ACh at the synapse. Which of these would be affected by sarin?

ACh receptor activity

In a 2019 study, researchers found that an infection by the measles virus (MV) has an effect on the innate immune system. Antibodies to many different viruses were measured in children at Time 1 and Time 2, 5 months apart. The children had no other infections during that time.

Antibodies normally decrease over time

This diagram shows a ribosome making a protein from mRNA. Which could be the protein shown by the red arrow being made?

Aquaporin

The spindle assembly checkpoint (SAC) requires that every kinetochore be bound to a spindle microtubule. Where specifically will cell division stop if the cell cannot deactivate the SAC?

Before Anaphase

If fertilization is delayed, what would be affected?

Bicoid protein production would be delayed

Which is true of both muscle contraction and flagella whipping ?

Both depend on cytoskeletal polymers sliding relative to each other

What is similar about generating the ester linkage to make a lipid and generating a peptide bond to extend a polypeptide chain?

Both reactions are dehydration reactions

Which of the following has a higher proportion of oxygen to carbon?

Carbohydrates

Zebrafish are generally diploid, but haploid fish can be generated by fertilizing eggs with UV-inactivated sperm. The cells derived from this newly fertilized zygote could:

Carry out mitosis

A codon of 5' GUC 3':

Corresponds to a template strand of 3' CAG 5'

Two mature B cells make different antigen receptors. This difference is because:

Deletion by recombinase

We discussed a paper in the Basics video where the authors analyzed the role of Gpld1 in young blood and after exercise, and the effects of Gpld1 on learning and on neurogenesis. In similar experiments, they analyzed the role of Pon1 in the blood, and on learning. They injected aged sedentary mice with Pon1, and tested how quickly the mice could learn their way through a maze.

Delivering additional Pon1 does not improve learning in these mice, above normal learning

Why are action potentials generally not found in dendrites?

Dendrites don't have voltage-gated sodium channels

Scientists are studying the effects of a drug, LLOMe, on the accumulation of the protein Galectin-3 into aggregations in the cell.

Discrete

Drugs 1 through 3 act on different parts of the HIV infection cycle. Which is likely to be a virus binding inhibitor rather than a reverse transcriptase inhibitor or a DNA insertion inhibitor?

Drug 1

Researchers were interested in the effect of higher CO2 on photosynthesis. Here they measure the effect of elevated CO2 on the activity of enzyme PPDK, which helps transport CO2 into plant cells.

Elevated CO2 causes changes in gene expression

A new drug is being developed which will prevent viruses from copying their nucleic acids. Sofosbuvir looks like this: The active form of sofosbuvir looks most like a:

Guanine

A replicating chromosome is touching:

Helicase

When Mendel crossed yellow round peas to green wrinkled peas, he got all yellow round peas in the F1 generation. When he crossed F1 yellow round peas to other F1 yellow round peas, he got a mixture of plants in the F2 generation, yellow round, green wrinkled, yellow wrinkled, and green round. The fact that the yellow allele separates from the green allele (and, similarly, that the round allele separates from the wrinkled allele), reflects

Homologous chromosomes are paired up on the metaphase plate, then separate during meiosis 1

In cellular respiration, where do the electrons that are pulled off of glucose end up?

In water molecules in the mitochondrial matrix

Researchers are investigating the mechanism of a new actin binding drug, MiuA. According to this graph, MiuA:

Increases new actin filament formation

What is the most direct method of increasing the dry mass of a tomato plant?

Increasing CO2 in the air

In classic experiments, scientists could dissect out the dorsal lip of the frog gastrula, transplant it onto another gastrula, and get a frog tadpole with 2 heads (that wouldn't survive very long). This is a demonstration of the developmental process of

Induction

Cholera toxin causes excess fluid in the intestines. In 1975, researchers believed GM1 was the receptor on the cell membrane of the gut cell where cholera toxin binds. To test this, they prepared segments of rabbit intestine with different amounts of GM1 and exposed it to both the toxin and an inhibitor to GM1. Here are the results:

Inhibiting GM1 inhibits the action of the toxin

Which of the following will be most affected by a membrane that is less fluid?

LDL transport

Thyroid hormone is released by the thyroid gland and binds to a protein in the nucleus of many different cells. This is an example of which type of signaling?

Long distance

The energy from ATP hydrolysis is used to drive

Mitotic spindle pole separation during anaphase/telophase

In the state shown, which of these molecules are oxidized molecules and which are reduced molecules?

Molecule A & NAD+ are oxidized, and Molecule B and NADH are reduced

This is the region around the beginning of a gene. What are the first few amino acids of the polypeptide this encodes? 3' ATG TAC ATG 5'

N- Met Tyr -C

What product from the Calvin cycle is used in the light reactions?

NADP+

Which of the following is NOT a strategy used by cells to regulate the activity of their genes?

Nucleotide mutation

Which is true of a single chromosome during meiosis 1?

Only one kinetochore on that chromosome will be bound by kinetochore MTs

We discussed microtubule nucleators at the minus end of MTs, and microtubule associated proteins (MAPs like Tau) that bind along the length of MTs. In addition, there are also capping proteins that bind to the plus ends of microtubules. These (+) end MT capping proteins would most likely:

Slow MT shrinkage

Which is a form of passive transport?

Sodium diffusing through a membrane channel

Which membrane protein does NOT significantly contribute to resting membrane potential?

Sodium leak channel

A "lipid raft" is an area of the plasma membrane in animals that tends to contain a special group of lipids and proteins that are packed more tightly together. Based on this data, where "SM" is sphingomyelin and "CHO" is cholesterol, which can you conclude?

Sphingomyelin contains few carbon-carbon double bonds

The roundworm C. elegans normally moves by swimming in a sinusoidal wave (S), but mutations in genes important for the nervous system make the worms move by rolling (s). They are normally long and elegant (E), but mutations in skin genes can make them a dumpy shape (e). You breed an elegant sinusoidal swimmer to a dumpy roller. If the offspring you get are 212 elegant sinusoidal swimmers, 198 dumpy rollers, 222 dumpy sinusoidal swimmers, and 187 elegant rollers, then what were the genotypes of the parents you crossed?

SsEe x ssee

Which of the following is an element that is not one of the top 4 found in the body but regularly forms covalent bonds in biological molecules?

Sulfur

This is the activity of two enzymes, arginase and canavanase. Arginase (indicated with the triangles) is found in the liver. What can you conclude?

The pH of the liver is around 9.5

Researchers were interested in the effects of nitrate levels on the gene expression of various versions of a transcription factor called GATA in plants. This figure shows the effect of nitrates on the expression of several different GATA genes in plant parts. HN = high nitrates, LN = low nitrates.

The types of mRNA in a plant cell change when nitrate levels change

The spike protein on SARS-CoV-2 has undergone several mutations from the Delta strain to the Omicron strain, and previous monoclonal antibodies no longer work. Which is true?

The virus has new epitopes

What's a difference between a woman with one mutant allele for red-green colorblindness (an X linked recessive trait) and a man with one mutant allele of red-green colorblindness?

The woman can detect color in many/half cells in her retina, the man cannot detect color in any

Mouse fur color is controlled by the following alleles: A+, Ay, a, and at. These crosses produce these fur colors: A+ and A+ = dark grey A+ and Ay = yellow a and a = black at and at = black back and yellow belly. Which is most likely true?

There are multiple alleles for the A gene

What is the difference between S phase before mitosis versus S phase before meiosis 1?

There are no significant differences

What is one way that inhibitory inputs could cause IPSPs?

They could allow Cl- to flow into the cell

A person with familial hypercholesterolemia has incomplete dominance at both the cellular and physiological level. This disease is caused by defective LDL receptors. Which is true?

They have one mutant allele that prevents LDL receptor protein translation

Human bocavirus and canine parvovirus are both ssDNA viruses. Which is true?

They use the host cell's DNA polymerase

A particular Australian tick produces toxins that change muscle contraction. Researchers stimulated motorneurons, and recorded the response of muscle cells, either without or with tick toxin treatment. Based on this recording of the membrane potential of muscle cells after the neuron fired action potentials, what would you expect of muscles treated with toxin:

Treatment with toxin should cause muscles to contract less

Which of the following would normally NOT be found in the nucleus?

Tubulin

Compared to RNA vaccines, a DNA vaccine:

Uses a plasmid

Sister chromatids are formed:

Using semiconservative replication

This image is taken from a document explaining the best way to help children who are sick with vomiting or diarrhea to recover lost fluids.According to this document, which type of fluid should children drink in order to move the most water possible to the blood?

Water plus glucose plus sodium

Based on this pedigree, which is most likely to be the nature of this disorder?

X-linked recessive

Integrin is a cellular molecule that binds to both the extracellular matrix and actin filaments. Which is true of integrin?

it is an integral protein

A genetic disease causes the cell to fill with vesicles containing waste molecules that aren't broken down. This is likely a disease associated with:

lysosomes

NSC635326 is a chemical that was recently discovered to inhibit the spliceosome. In cells treated with NSC635326, which of these would accumulate?

mRNA that contains introns