BSC 1010 FINAL EXAM REVIEW
QUESTIONS WITH VERIFIED ANSWERS
(ALREADY GRADED A+)
Put the steps of the process of signal transduction in the order they occur:
1. A conformational change in the signal-receptor complex activates an enzyme.
2. Protein kinases are activated.
3. A signal molecule binds to a receptor.
4. Target proteins are phosphorylated.
5. Second messenger molecules are released. CORRECT ANSWER 3,1,5,2,4
Integrins are integral membrane proteins. They are often attached to . CORRECT
ANSWER cytoskeletal proteins and proteins in the extracellular matrix
Phosphorylation cascade involving a series of protein kinases are useful for cellular signal transduction
because they . CORRECT ANSWER amplify the original signal many times
The receptors doe steroid hormones are located inside the cell instead of on the membrane surface lik
e most other signal receptors. This is NOT a problem for steroids because .-
correct answer-
steroid hormones are lipid soluble, so they can readily diffuse through the lipid bilayer on the cell me
mbrane.
Which stateerning how the molecular composition of a plant cell wall compare with the extracellular
matrix of animal cells? CORRECT ANSWER
Plant cell wall fibers consist primarily of carbohydrates ECM fibers are dominated by proteins.
The structure that anchors adjacent epithelial cells via their cytoskeleton is the
CORRECT ANSWER desmosome
Activated signal receptors on the plasma membrane can carry out which two activities?
CORRECT ANSWER Catalyze receptor phosphorylation; activate G proteins
,Different cell types can respond differently to the same signaling molecule because .
CORRECT ANSWER each cell type converts the signal to a different metabolite.
When a lipid- soluble hormone enters a cell and binds a receptor, what happens to the receptor?
CORRECT ANSWER It enters the nucleus and activates genes.
Signaling pathways always work in complete isolation from one another. CORRECT ANSWER False
In eukaryotic cells, chromosomes are composed of . CORRECT ANSWER DNA and
proteins
Forms of the Ras protein found in tumors would cause which of the following? CORRECT
ANSWER DNA replication to be hyperactive.
The mitotic spindle is a micro tubular structure that is involved in . CORRECT
ANSWER separation of sister chromatids.
What is the structure of mitosis promoting factor (mpf)? CORRECT
ANSWER A cyclin protein bound to a cyclin-dependent kinase.
Which of the following would be used to differentiate between benign and malignant tumors?
CORRECT ANSWER The ability to invade other tissues
Most cancer cells have defects in either growth signaling pathways or cell cycle control processes.
CORRECT ANSWER True
What is the spindle apparatus? CORRECT ANSWER
The microtubule structure that separates chromosomes
The process of cytokinesis occurs differently in plants and animals. CORRECT ANSWER True
, Proteins that are involved in the regulation of the cell cycle and that show fluctuations in concentratio
n during the cell cycle are called . CORRECT ANSWER cyclins
QUESTIONS WITH VERIFIED ANSWERS
(ALREADY GRADED A+)
Put the steps of the process of signal transduction in the order they occur:
1. A conformational change in the signal-receptor complex activates an enzyme.
2. Protein kinases are activated.
3. A signal molecule binds to a receptor.
4. Target proteins are phosphorylated.
5. Second messenger molecules are released. CORRECT ANSWER 3,1,5,2,4
Integrins are integral membrane proteins. They are often attached to . CORRECT
ANSWER cytoskeletal proteins and proteins in the extracellular matrix
Phosphorylation cascade involving a series of protein kinases are useful for cellular signal transduction
because they . CORRECT ANSWER amplify the original signal many times
The receptors doe steroid hormones are located inside the cell instead of on the membrane surface lik
e most other signal receptors. This is NOT a problem for steroids because .-
correct answer-
steroid hormones are lipid soluble, so they can readily diffuse through the lipid bilayer on the cell me
mbrane.
Which stateerning how the molecular composition of a plant cell wall compare with the extracellular
matrix of animal cells? CORRECT ANSWER
Plant cell wall fibers consist primarily of carbohydrates ECM fibers are dominated by proteins.
The structure that anchors adjacent epithelial cells via their cytoskeleton is the
CORRECT ANSWER desmosome
Activated signal receptors on the plasma membrane can carry out which two activities?
CORRECT ANSWER Catalyze receptor phosphorylation; activate G proteins
,Different cell types can respond differently to the same signaling molecule because .
CORRECT ANSWER each cell type converts the signal to a different metabolite.
When a lipid- soluble hormone enters a cell and binds a receptor, what happens to the receptor?
CORRECT ANSWER It enters the nucleus and activates genes.
Signaling pathways always work in complete isolation from one another. CORRECT ANSWER False
In eukaryotic cells, chromosomes are composed of . CORRECT ANSWER DNA and
proteins
Forms of the Ras protein found in tumors would cause which of the following? CORRECT
ANSWER DNA replication to be hyperactive.
The mitotic spindle is a micro tubular structure that is involved in . CORRECT
ANSWER separation of sister chromatids.
What is the structure of mitosis promoting factor (mpf)? CORRECT
ANSWER A cyclin protein bound to a cyclin-dependent kinase.
Which of the following would be used to differentiate between benign and malignant tumors?
CORRECT ANSWER The ability to invade other tissues
Most cancer cells have defects in either growth signaling pathways or cell cycle control processes.
CORRECT ANSWER True
What is the spindle apparatus? CORRECT ANSWER
The microtubule structure that separates chromosomes
The process of cytokinesis occurs differently in plants and animals. CORRECT ANSWER True
, Proteins that are involved in the regulation of the cell cycle and that show fluctuations in concentratio
n during the cell cycle are called . CORRECT ANSWER cyclins
