Quest 2
A cell should not divide when...
there are not enough nutrients
A gene that encodes a protein necessary for a cell to stop at checkpoints is an example of...
tumor-suppressor gene
What is the main difference between innate and adaptive immunity?
innate=always the same, first line of defense adaptive= creates antibodies to fight specific antigen
The monomers of DNA and RNA are...
nucleotides
The term "semiconservative replication" refers to the fact that...
the DNA molecule includes a parental strand and newly created DNA strand
During the metaphase checkpoint, the cell checks...
whether its chromosomes are properly attached to microtubules
rod-shaped bacteria are called
bacilli
List two ways in which the structure of DNA and RNA are different.
1. DNA is a double strand; RNA is a single strand 2. In DNA, C pairs with G and A pairs with T, but in RNA, C pairs with G and A pairs with U.
List the correct order of events/stages in M phase of the cell cycle.
1. Prophase 2. Prometaphase 3. Metaphase 4. Anaphase 5. Telophase 6. Cytokinesis
List two ways in which the structures of DNA and RNA are similar.
1. both have hydrogen bonds between nucleotides 2. both have a sugar phosphate backbone help together by covalent bonds
List two reasons why a cell might normally undergo division...
1. for growth 2. to repair tissue
List two internal defenses that participate in innate immunity.
1. interferons 2. macrophages/WBCs
List the requirements for transcription.
1. mature DNA parent strand 2. RNA polymerase 3. free nucleotides
List two external barriers that participate in innate immunity.
1. skin 2. mucous membranes
The chemotherapeutic pactlitaxel (taxol) is known as a microtubule stabilizer. During which phase of mitosis does this drug act?
Anaphase
Which of the following is the correct order of events in the cell cycle? a. G1, G2, S, mitosis, cytokinesis b. G1, S, G2, mitosis, cytokinesis c. S, G1, G2, cytokinesis, mitosis d. S, G1, G2, mitosis, cytokinesis
B
carries out antibody-mediated immune response
B cell
Which of the following statements regarding DNA is false? a. DNA molecule has a uniform diameter b. In a DNA molecule, adenine bonds to thymine and guanine to cytosine. c. the phosphate is in the form of a double helix d. the sequence of nucleotides along the length of a DNA strand is restricted by the base-pairing rules
D.
BRCA1 and BRCA2 are important for which cellular process?
DNA repair
What sequence of events usually occurs in the process of protein synthesis?
DNA, RNA, protein
What is the function of tRNA molecules during translation?
They carry amino acids to the ribosome
Consider a cell that underwent mitosis but not cytokinesis. The result would be...
a cell with two nuclei
What is a mutation?
any change in the nucleotide sequence of the molecule
What term describes a harmless, noncancerous or precancerous tumor?
benign
What is the name for the region toward the middle of a replicated chromosome where sister chromatids are connected?
centromere
attacks infected body cell
cytotoxic T cell
Which of the following is not a part of normal mRNA processing? a. a cap is added to the 5' end of the molecule b. the introns are removed during a process known as splicing c. A poly(A) tail is added to the 3' end of the molecule d. the exons are removed during a process known as splicing
d.
Which of the following statements about DNA polymerase is false? a. DNA polymerase is required for DNA replication b. DNA polymerase is an enzyme c. Both parental strands of DNA serve as templates for DNA polymerase d. DNA polymerase incorporates new amino acids into the growing DNA strand
d.
Which of the following statements regarding the genetic code is true? a. the genetic code is universal b. the genetic code is redundant c. the genetic code is not ambiguous d. all of the above are true
d.
A scientist who observes cancer cells under a microscope would likely see
disorganized cells
Which of the following contribute to the regulation of gene expression? a. transcriptional activators b. transcriptional repressors c. mRNA degradation d. protein degradation e. all of above are correct
e.
Which of the following is a common feature of cancer cells? a. anchorage dependence b. contact inhibition c. metastasis d. uncontrolled division e. two of above answers are correct
e.
_____ are toxic proteins secreted by pathogenic bacteria, whereas ____ are components of the outer membrane of gram-negative pathogens. a. endotoxins/phosphotoxins b. endotoxins/botulinum toxins c. toxozymes/endotoxins d. exotoxins/enterotoxins e. exotoxins/endotoxins
e.
phagocytic WBC
macrophage
Which RNA molecules carries the sequence of nucleotides that determines the order of amino acids in a protein?
messenger RNA (mRNA)
The multiple-hit model of cancer means that...
multiple mutations are required to cause most forms of cancer