Module Exam 2 - Biology

differentiated cells, such as nerve cells, would be in which of the following stages of the cell cycle

G0

which of the following organelles would form a membrane-bound package, also known as a vesicle

Golgi apparatus

Limit to cell size - surface area to volume ratio

Higher the ratio of surface area to internal volume = faster exchange of materials within environment Lower the ratio of surface area to interval volume = slower exchange of materials within environment

which of the following statements is correct regarding the events of the cell cycle

Interphase consists of G1, S, and G2.

Microscopes

Light microscope = allows for visibility but not seeing much of its complexity Electron microscope = allows for surface visibility to see features and fine details Scanning Probe microscope = physically scans surface of cell / able to distinguish objects of a nanometer in size

nuclear division occurs during

M phase

the drug chloral hydrate prevents elongation of microtubules. During which stage of the cell cycle would chloral hydrate be most harmful

M phase

If a cell stops at the G1 checkpoint, this is most likely due to what problem?

There is DNA damage.

surface-to-volume ratio is an important characteristic for cell functions; some cells increase their ratio by

developing finger-like projections.

a translocation may lead to cancer if it

disrupts control of expression of genes that regulate the cell cycle.

a prokaryotic cell

does not have a membrane-bound nucleus

a mutation that causes an increase in function in a tumor suppressor gene would not likely cause cancer because a tumor suppressor protein

does not promote cell division

which of the following is an inactive region of DNA

heterochromatin

the presence of which protein is required in order for chromatin to compact correctly within the nucleus

histone

which of the following is mismatched

interphase-shortest stage of the cell cycle

compared with a eukaryotic cell, a prokaryotic cell

lacks organelles beyond ribosomes

Compared with a eukaryotic cell, a prokaryotic cell

lacks organelles beyond ribosomes.

carrie would like to observe the cilia on the surface of a live paramecium-a single-celled organism. The best device to do this would be an

light microscope

which of the following is a correct match

lysosomes - cellular digestion

If tumor cellshave afaulty, nonfunctional proteinase, they will be unable to undergo which of the following processes? a. mitosis b. mutations c. metastasis d. apoptosis e. angiogenesis

metasis

a mitotic spindle is composed of ____, which originate from the ____

microtubules; centrosome

a mitotic spindle is composed of ______ which originate from the ____

microtubules; centrosome

a cell cannot produce enough energy to function properly most likely has a problem with its

mitochondria

which of the following organelles would be abundant in a sperm cell that is actively swimming towards an egg cell

mitochondria

which of the following is a correct matching of an organelle and its function

mitochondrion - cellular respiration

A defect in DNA ligase would most likely result in

normal replication, but gaps remaining in the sugar-phosphate DNA backbone.

chromatin wrapped around histones form a bead-like structure known as a

nucleosome

which of the following structures would not be found only in a eukaryotic cell

nucleus

the nucleus has a double membrane that encloses the DNA. Inside the nucleus, the DNA acts as the template to produce mRNA and ribosomes. To exit the nucleus, these molecules must

pass through pores that span both membranes.

what must materials pass through to enter or to leave a cell

plasma membeane

Identify the organelle - function pairing that is mismatched.

plasma membrane - outermost barrier of a plant cell

Some of the drugs used in chemotherapy work by

preventing spindle formation

The drug chloral hydrate prevents elongation of microtubules by preventing the addition of new subunits to the growing end. During which stage of mitosis would chloral hydrate be most harmful?

prophase

the figure below shows a cell in the mitotic stage of

prophase

Plasma Membrane - fluid mosaic structure

protein molecules make up a pattern within fluid bilayer short chains of sugars attached to surface of some proteins forming glycoproteins glycoproteins = establishes identity of the cell

which structures determine the flexibility of the extracellular matrix

proteins

which of the following lacks a membrane

ribosomes

which of the following organelles lacks a membrane?

ribosomes

eukaryotic cells have DNA enclosed in a double membrane called the nucleus, the nucleus functions to

separate the DNA from other activities that occur in the cytoplasm.

a centromere holds together two

sister chromatids

which lifestyle choice is responsible for 90% of the cases of lung cancer among men?

smoking

a proto-oncogene differs from a tumor suppressor gene because a photo-cogene

stimulates mitosis in a normal cell, whereas a tumor suppressor gene inhibits mitosis

which of the following contains the anticodon

tRNA

Embryonic cells and cancer cells are similar because

telomerase is active

ben was looking at onion root tip cells under the microscope in biology class. He saw one cell that had two nuclei within it. what stage of the cell cycle is this cell in

telophase/cytokinesis

cytokinesis in plants occurs as ____ and in animals as _____

the Golgi apparatus produces membrane-bound vesicles filled with materials to make the cell wall; actin fibers pull the membrane inward until the two sides touch

a tumor suppressor gene undergoes a mutation that causes it to lose its normal function. what would be the most likely result of this mutation

the cell no longer responds to signals that cause it to stop dividing or undergo apoptosis

which of the following is an inaccurate statement about mitosis

the cells arising from mitosis contain only half of the necessary genetic material

in which ways are vesicles different from vacuoles

they are smaller

which of the following is a function of glycoproteins

to permit cells to recognize one another

The term metastasis refers to the fact that cancer cells tend to

to spread

transcription activators are different from transcription factors in that

transcription factors are required for RNA polymerase binding, while transcription activators accelerate transcription.

when a portion of a chromosome breaks off and attaches to a different chromosome, this is called a

translocation

proteins within the extracellular matrix play a role in communicating between the matrix and the cytoskeleton

true

Plasma Membrane - structure + function

- acts as a boundary between inside / outside of a cell - vital to cell because it acts as a gatekeeper, regulating the passage of molecules + ions into and out of cell

cells

- diverse in shape and function - cells specialized to perform specific functions - complex but tiny, requiring specific microscopes to be seen

Plasma Membrane - structure

- made up of phospholipid bilayer with numerous proteins embedded in it - within bilayer, polar (hydrophilic) heads are oriented in two directions outer layer = heads face external environment interior layer = heads face to interior cytoplasm NonPolar tails = point toward each other, in space between layers, where there is no H2O

If a cell has 46 chromosomes at the beginning of mitosis, then at the end of anaphase there would be a total of

92 chromosomes

which of the following is a characteristic of cancer cells

All of the above answers are characteristics of cancer cells.

which of the following is a characteristic of cancer cells

All of the above are characteristics of cancer cells.

which of the following is a type of intracellular protein

All of the above are types of intracellular proteins.

which of the following is a possible function of the extracellular matrix in animal cells

All of the answers are possible functions of the extracellular matrix.

Cells grown in a petri dish tend to divide until they form a thin layer covering the bottom of the dish. which of the following statements explains why this occurs

Cell division can be inhibited by the proximity of other cells of the same type, a process called contact inhibition.

Cells grown in a petri dish tend to divide until they form a thin layer covering the bottom of the dish. which of the following statements explains why this occurs?

Cell division can be inhibited by the proximity of other cells of the same type, a process called contact inhibition.

which of the following enzyme is needed to reseal breaks in the sugar phosphate backbone during replication

DNA ligase

a tumor suppressor gene undergoes a mutation that causes it to lose its normal function, what would be the most likely result of this mutation

The cell no longer responds to signals that cause it to stop dividing or undergo apoptosis.

a positive genetic test for telomerase indicates that

a cell is probably cancerous

As a molecule moves through the plasma membrane it passes through

a hydrophilic layer of phospholipid heads, then a hydrophobic layer of phospholipid tails, and then another hydrophilic layer of phospholipid heads.

failure to remove introns from a primary mRNA would most likely cause

abnormal translation.

which is the most common type of intercellular junction between cells of the bladder

adhesion junctions

For a DNA strand composed of the sequence AGT in the 5' to 3' direction, the free phosphate is on the ________ nucleotide and the free hydroxyl is on the ________ nucleotide.

at

which of the following would increase your risk of cancer

avoiding a high-fiber, low-sodium diet

A cell being observed under a microscope has a cell wall, plasma membrane, ribosomes, and chromosomal material that is not found in a nucleus. Based on this information, the cell could be a

bacterial cell

Mitochondria are found in _____.

both plant cells and animal cells

which of the following series of events are in the correct order?

chemical binds to receptor, signal transduction pathway stimulates transcription activator, target gene is transcribed and translated

Which cancer therapy can lead to side effects such as nausea and hair loss?

chemotherapy

chromosomes are made from

condensed chromatin

plant cells have plasmodesmata that

connect the cytoplasm of one cell with that of another.