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문제 1
The smallest unit capable of life by itself is:
a. The organ
b. The organelle
c. The tissue
d. The cell
e. The nucleus
문제 2
The major types of lipids found in the plasma membranes are (choose two):
a. Cholesterol
b. Triglycerides
c. Phospholipids
d. Fat-soluble vitamins
문제 3
Membrane junctions that allow nutrients or ions to flow from cell to cell are:
a. Desmosomes
b. Gap junctions
c. Tight junctions
d. All of these
문제 4
Osmosis always involves:
a. A selectively permeable membrane
b. A difference in solute concentration
c. Diffusion
d. Active transport
e. a, b, and c
문제 6
The nuclear substance composed of histone proteins and DNA is:
a. Chromatin
b. The nucleolus
c. Nucleoplasm
d. Nuclear pores
문제 7
The information sequence that determines the nature of a protein is:
a. Nucleotide
b. Gene
c. Triplet
d. Codon
문제 8
The phase of mitosis during which centrioles reach the poles and chromosomes attach to the spindle is
a. Anaphase
b. Metaphase
c. Prophase
d. Telophase
문제 9
The RNA synthesized on one of the DNA strands is:
a. mRNA
b. tRNA
c. rRNA
d. all of these.
문제 10
The RNA species that travels from the nucleus to the cytoplasm carrying the coded message specifying the sequence of amino acids in the protein to be made is
a. mRNA
b. tRNA
c. rRNA
d. all of these
문제 11
Cells lining the trachea have whiplike motile extensions on their free surfaces. What are these extensions, what is their source, and what is their function?
문제 12
A physiologist observes that the concentration of sodium inside a cell is decidedly lower than that outside the cell. She also observes that there is a small leakage of sodium into the cell. What cellular process prevents the sodium concentration gradient from disappearing?
a. Osmosis
b. Diffusion
c. Primary active transport
d. Secondary active transport
문제 13
If DNA has a sequence of AAA, then a segment of mRNA synthesized on it will have a sequence of:
a. TTT
b. UUU
c. GGG
d. CCC
문제 14
A nerve cell and a lymphocyte are presumed to differ in their:
a. Specialized structure
b. Suppressed genes and embryonic history
c. Genetic information
d. a and b, e. a and c
문제 15
A pancreas cell makes proteins (enzymes) that it releases to the small intestine. Which of the following best describes the path of these proteins from synthesis to exocytosis at the pancreatic cell's plasma membrane (PM)? a. Golgi → rough ER → PM, b. smooth ER → Golgi → lysosome → PM, c. rough ER → Golgi → PM, d. nucleus → Golgi → PM.
문제 16
The type of fracture that occurs in osteoporosis:
문제 17
Comment on the role of the sodium-potassium pump in maintaining a cell's resting membrane potential.
문제 18
Differentiate between primary and secondary active transport processes.
문제 19
Two examples of chemotherapeutic drugs (drugs used to treat cancer) and their cellular actions are listed below. Explain why each drug could be fatal to a cell. • Vincristine (brand name Oncovin): damages the mitotic spindle • Doxorubicin (Adriamycin): binds to DNA and blocks mRNA synthesis
문제 20
In their anatomy lab, many students are exposed to the chemical preservatives phenol, formaldehyde, and alcohol. Our cells break down these toxins very effectively. What cellular organelle is responsible for this?
문제 21
Cell division typically yields two daughter cells, each with one nucleus. How is the occasional binucleate condition of liver cells explained?
문제 22
A 'red-hot' bacterial infection of the intestinal tract irritates the intestinal cells and interferes with digestion. Such a condition is often accompanied by diarrhea, which causes loss of body water. On the basis of what you have learned about osmotic water flows, explain why diarrhea may occur.
문제 23
Dynein is missing from the cilia and flagella of individuals with a specific inherited disorder. These individuals have severe respiratory problems and, if males, are sterile. What is the structural connection between these two symptoms?
문제 24
Explain why alcoholics are likely to have much more smooth ER than teetotalers.
문제 25
Fresh water is a precious natural resource in Florida and it is said that supplies are dwindling. Desalinizing (removing salt from) ocean water has been recommended as a solution to the problem. Why shouldn't we drink salt water?