Cell Biology Exam 3

What is the order of the cell cycle?

G1, S, G2, M

In a monohybrid cross, what is the expected genotypic and phenotypic ratio?

G: 1DD:2Dd:1dd P: 3:1

What is the nucleotide bound by tubulin?

GTP/GDP

Which junctional complex is made of connexin proteins?

Gap junction

Hexokinase catalyzes the first step of glycolysis that produces _____.

Glucose 6-phosphate

GPCR activation of phospholipase C next produces ______.

IP3 and diacylglycerol

Where does oxidative phosphorylation take place?

Inner Mitochondrial membrane

Desmosomes are associated with the _____ cytoskeleton.

Intermediate filament

What does a malignant tumor do that a benign tumor does not?

It invades and spread to other tissues

What are the 2 moto proteins associated with microtubules?

Kinesins Dynein

What is the complex that assembles on the chromosome centromere and attaches to microtubules in the miotic spindle?

Kinetochore

What is an example given for molecular switches that toggle between off and on states?

transcription factor

Slower signaling pathways (1 hour or more) mediate their signals via ____.

transcriptional mechanisms

Rapid signaling pathways mediate their signals via ___. A.) Altered insulin product B.) Altered receptor expression C.) Altered protein synthesis D.) Altered transcript pathways E.) Altered protein function

E.) Altered protein function

This organelle sequesters (stores) calcium for release in cell signaling, like muscle contraction

ER

From largest to smallest diameter, what is the correct order for the cytoskeleton filaments.

- Microtubules - Intermediate filaments - Actin

Name the component in signal transduction (Label 1-4)

1. Ligand 2. Receptor 3. Signal transduction molecules / intracellular signaling proteins. 4. effector protein

A diploid cell containing 32 chromosomes will make a haploid cell containing how many chromosomes?

16

In the absence of recombination how many genetically different types of gametes can an organism with five homologous chromosome pairs produce?

32

Which of the following reasons was essential for Mendel's law of independent assortment? A.) All of the traits that Mendel examined involved genes that did not display linkage. B.) Several of the phenotypes that Mendel examined involved color. C.) Mendel observed chromosomal segregation in pea-plant cells. D.) Mendel carried out his experiments on plants and not on fungi.

A.) All of the traits that Mendel examined involved genes that did not display linkage.

During fertilization in humans, _____. A.) a wave of Ca2+ ions is released in the fertilized egg's cytoplasm. B.) only one sperm binds to the unfertilized egg. C.) a sperm moves in a random fashion until it encounters an egg. D.) several sperm pronuclei compete in the cytoplasm to fuse with the egg and nucleus.

A.) a wave of Ca2+ ions is released in the fertilized egg's cytoplasm.

What is the nucleotide bound by actin?

ATP/ADP

After the first meiotic cell division ____. A.) Two haploid gametes are produced. B.) Cells are produced that contain the same number of chromosomes as somatic cells. C.) The number of chromosomes will vary depending on how the paternal and maternal chromosomes align at the metaphase plate. D.) DNA replication occurs

B.) Cells are produced that contain the same number of chromosomes as somatic cells.

During recombination _____ A.) Sister chromatids undergo crossing over with each other. B.) Chiasmata hold chromosomes together. C.) One crossover event occurs for each pair of human chromosomes. D.) The synaptonemal complex keeps the sister chromatids together until anaphase 2.

B.) Chiasmata hold chromosomes together.

What is the order of the cell cycle phases? A.) G1, M, S. G2 B.) M, G1, S, G2 C.) G2, M, S, G1

B.) M, G1, S, G2

Which of the following statements is false? A.) asexual reproduction typically gives rise to offspring that are genetically identical. B.) Mutations in somatic cells are passed onto individuals of the next generation. C.) Sexual reproduction allows for a wide variety of gene combinations. D.) gametes are specialized sex cells.

B.) Mutations in somatic cells are passed onto individuals of the next generation.

Which one of these proteins is a motor that uses the microtubule cytoskeleton? A.) Cadherin B.) kinesin C.) myosin D.) keratin

B.) kinesin

Haplotype blocks can be seen in humans because ______. A.) disease genes are found in haplotype blocks. B.) modern humans descended from a relatively small population of about 10,000 individuals that existed about two thousand generations ago. C.) some of our human ancestors interbred with Neanderthals. D.) new mutations cannot be introduced into existing haplotype blocks.

B.) modern humans descended from a relatively small population of about 10,000 individuals that existed about two thousand generations ago.

Which of the following is an actin filament structure in cells? A.) axoneme B.) basal body C.) microvilli D.) mitotic spindle

C.) microvilli

____ is the process of breaking down food molecules in successive steps.

Catabolism

In the absence of recombination, how man genetically different types of gamete can an organism with five homologous chromosome pairs produce? A.) 5 B) 10 C.) 32 D.) 64

C.) 32

Signaling that communicates locally, within a short distance through extracellular fluid is called ___ signaling. A.) Endocrine B.) Synaptic C.) Paracrine D.) Contact Dependent E.) Instagram

C.) Paracrine

There are organisms that go through meiosis but do not undergo recombination when forming haploid gametes. Which of the following statements correctly describes the gametes produced by such an organism. (Assume that these organisms are diploid, that each of the two homologous chromosomes are genetically distinct as typically found in the wild, and that these organisms have more than one chromosome.) A.) All gametes formed during a single meiosis will be identical. B.) Due to the random assortment of homologs, each of the gametes formed during a single meiosis will be different. C.) This organism could potentially produce 2n genetically distinct gametes, where n is its haploid number of chromosomes. D.) The fusion of any two gametes produced by such an organism that does not undergo recombination during meiosis will create a cell that is genetically identical to that individual.

C.) This organism could potentially produce 2n genetically distinct gametes, where n is its haploid number of chromosomes.

Which of the following does NOT describe a situation of asexual reproduction? A.) A bacterium multiplying by simple cell division. B.)Using part of a plant to create a new independent plant. C.) Using in vitro fertilization to combine a sperm and an egg to create an embryo. D.) The parthenogenetic development of eggs produced by some species of lizards.

C.) Using in vitro fertilization to combine a sperm and an egg to create an embryo.

The single-nucleotide polymorphisms found in the human population ____. A.) are important for genetic mapping because they represent mutations in genes important for human disease. B.) are rarely found among blood relatives. C.) can be linked into haploblocks. D.) arose mainly during the past 10,000 years.

C.) can be linked into haploblocks.

GPCR activation of phospholipase-C _____ A.) produces cAMP B.) cleaves notch protein to make delta C.) cleaves a phosphoinositol lipid to make IP3 and diacylglycerol D.) activates protein kinase A

C.) cleaves a phosphoinositol lipid to make IP3 and diacylglycerol

Which effect is likely to occur more rapidly in response to an extracellular signal? Changes in protein phosphorylation OR Changes in proteins being synthesized

Changes in protein phosphorylation

receptor-mediated endocytosis first internalizes cargo molecules via ____.

Clathrin coated vesicles

Receptor mediated endocytosis first internalizes cargo molecules via

Clathrin coated vesicles.

In which cellular location would you expect to find ribosomes translating mRNAs that encode ribosomal proteins?

Cytoplasm

Where are proteins in the chloroplast synthesized?

Cytosol and the chloroplast.

Which of the following statements most correctly describes meiosis? A.) Meiosis involves two found of DNA replication followed by a single cell division. B.) Meiosis involves a single round of DNA replication followed by four successive cell divisions. C.) Meiosis involves four rounds of DNA replication followed by two successive cell divisions. D.) Meiosis involves a single round of DNA replication followed by two successive cell divisions.

D.) Meiosis involves a single round of DNA replication followed by two successive cell divisions.

Imagine Meiosis in a diploid organism that only has a single chromosome. Like most diploid organisms, it's received one copy of this chromosome from each of its parents and the two homologs are genetically distinct. If only a single homologous recombination event occurs during meiosis, which of the following choices below correctly describes the four gametes found? A.) None of the gametes will contain chromosomes identical to the chromosomes found in the original diploid cell. B.) All four of the gametes will have chromosomes identical to the chromosomes found in the original diploid cell. C.) Three of the gametes will have chromosomes identical to the chromosomes found in the original diploid cell, while one of the gametes will have chromosomes that are different. D.) Two of the gametes will have chromosomes identical to the chromosomes found in the original diploid cell, two of the gametes will have chromosomes that are different.

D.) Two of the gametes will have chromosomes identical to the chromosomes found in the original diploid cell, two of the gametes will have chromosomes that are different.

Loss of function mutations __________. A.) cause the production of proteins that are active in inappropriate circumstances. B.) will usually show a phenotype when heterozygous. C.) are only present in a population at barely detectable levels. D.) are usually recessive.

D.) are usually recessive.

What is the process of rapid switching between microtubule growth and shrinkage called?

Dynamic instability

What type of pluripotent stem cell line is derived from the inner cell mass of a mammalian blastocyst stage embryo?

Embryonic stem cell line

T/F: Mutations in somatic cells are passed on to individuals of the next generation.

False, only germ line is transmitted.

Growth factor receptor tyrosine kinases activate Ras, which leads to the activation of _____ cascade.

Map kinase

What is the activity that drives anaphase A?

Microtubule catastrophe

What is the nucleotide bound by intermediate filament?

None

Animal cells assemble intermediate filament proteins on the inner surface of the nuclear membrane, which are called ______.

Nuclear lamina

What extracellular signal regulate commitment to start of the cell cycle.

Nutritional conditions and mitogens.

Which stage in the breakdown of glucose generates the most ATP?

Oxidative phosphorylation

At what miotic phase does the nuclear envelope break down and the spindle poles form?

Prometaphase

The electron transport chain converts high energy electron movements into _____.

Proton motive force

The final metabolite produced by glycolysis is _____.

Pyruvate

The signal recognition particle transiently binds the _____ and _____.

Signal sequence and ribosomes

The photosystems in chloroplast contain hundreds of chlorophyll molecules, most of which are part of ______.

The antenna complex.

What is the large conformational change in myosin head that occurs after binding the actin filament and release of the inorganic phosphate after ATP cleavage called?

The power strokes.

The following happens when a GPCR activates a G-protein

The subunit exchanges its bound GDP for GTP

What is the role of molecular oxygen in the electron transport chain.

The ultimate electron acceptor

If a stem cell divides and one of its daughter cells goes on to become a terminally differentiated cell, then what is the fate of the other daughter cell.

To become a stem cell with the same potency as the mother cell.

What is the role of cyclin in the cyclin Cdk complex?

To bind and activate Cdk activity.

The ER membrane is contiguous with the outer nuclear membrane.

True

At metaphase, chromatid pairs ____.

align at the metaphase plate

Adenylyl cyclase enzyme catalyzes the production of ____.

cAMP

Name a component of the electron transport chain that does not act as a proton pump.

cytochrome c ubiquitin

NADH and FADH2 pass their high energy electrons to the _____ in the inner mitochondrial membrane

electron-transport chain

Which cytoskeletal filament system does NOT have polarity?

intermediate filaments

Chemiosmotic coupling is a mechanism that couples the synthesis of ATP with ____.

membrane transport proteins

Signaling that communicates systematically, throughout the body is called ____ signaling.

paracrine

This organelle is the location of oxidative breakdown of toxic molecules

peroxisome

Numerous ______ are bound to the cytoplasmic face of the rough ER membrane

ribosomes