🧪 SAT MCQ Quiz Hub

1. In human DNA, adenine (A) makes up approximately 30.9% of the bases, and guanine (G) makes up approximately 19.9% of the bases; therefore the percentage thymine (T) and cytosine (C) are
29.4% T and 19.8% C
29.8% T and 29.8% C
19.8% T and 19.8% C
19.8% T and 29.4% C

2. If the chromosomes of a eukaryotic cell were lacking telomerase, the cell would
have a greater potential to become cancerous than one with telomerase
become increasingly shorter with each cycle of replication
not produce okazaki fragments
be unable to take up extraneous DNA from the surrounding solution

3. Which of the following statements concerning transcription and translation in eukaryotic cells is NOT correct?
Transcription results in the production of mRNA, whereas translation results in the production of polypeptides
Transcription occurs in the nucleus, whereas translation occurs in the cytoplasm
Transcription uses DNA as a template, whereas translation uses mRNA as a template
Transcription results in the production of polypeptides, whereas translation results in the production of mRNA

4. The open, less compacted form of DNA that is available for transcription is known as the
chromatin
heterochromatin
promotor
euchromatin

5. A sequence on a DNA molecule that recognizes specific transcription factors that can stimulate transcription of nearby genes is known as the
promotor
operator
enhancer
euchromatin

6. During the stage in which insertion of eukaryotic DNA into the plasmid vector occurs, the sticky ends formed by digestion of both DNA types with the same restriction enzyme may join in a recombinant molecule because
the eukaryotic DNA and plasmid DNA will have the same sequence
the eukaryotic DNA and plasmid DNA will have complementary sequences
the plasmid DNA can join with any eukaryotic DNA, regardless of sequence
the plasmid DNA and the eukaryotic DNA cannot join together due to differences in the structure of their DNA molecules

7. Which of the following statements is NOT true of restriction enzymes?
Restriction enzymes protect their bacterial host against intruding foreign DNA from viruses or other bacterial cells
Most restriction enzymes are named after the bacterial organism from which they were first isolated
Each restriction enzyme recognizes a specific sequence of bases on the DNA molecule
Each restriction enzyme cuts at random locations along the DNA molecule

8. The uptake of naked DNA from solution by bacterial cells is known as
transcription
electroporation
transduction
transformation

9. The classification of organisms into kingdoms has come under debate in recent years, with most of the debate focused on the
algae and fungi
prokaryotes and simple eukaryotes
algae and plants
fungi and plants

10. n the steps leading up to the origin of life on earth, early protobionts could not have evolved into living cells without both
competition for resources and the development of hereditary mechanisms
a semipermeable membrane and a nucleus
a semipermeable membrane and the ability to catalyze chemical reactions
a nucleus and the ability to catalyze chemical reactions

11. Which of the following statements about the lac operon is NOT true?
RNA polymerase can be blocked by an active repressor protein attached to the operator
RNA polymerase attaches at a site on the DNA strand, known as the promoter
There is a regulatory gene that is downstream from the structural genes that can inhibit transcription
The regulatory gene produces the active repressor

12. Which of the following statements about the HIV virus is NOT true?
The viral nucleotides contain ribose
HIV contains uracil, not thymine
HIV infection begins with the entrance of the virus into the host when the gp 120 and gp 41 function to pull the virus across the plasma membrane
HIV makes the host cell produce reverse transcriptase

13. All of the following are means of posttranscriptional control in eukaryotes EXCEPT
the capping of the 58 end with a modified guanosine triphosphate
the addition of a poly-A tail to the 38 end
the cutting out of introns by a spliceosome
the ligation of exons by DNA polymerase

14. Which of the following statements is NOT true concerning restriction fragment length polymorphisms (RFLPs)?
Suspects whose fragments do not match any other fragments at a crime scene can be vindicated
The polymerase chain reaction can be used to produce more copies of DNA obtained at a crime scene before RFLP analysis
Most RFLPs use radioactive probes
With the advent of PCR technology, restriction enzymes are no longer needed to perform RFLP analysis

15. The number of tRNA molecules required by eukaryotic organisms to ferry around the amino acids is
64
63
45
23

16. A student using a compound microscope with a 10X ocular lens and a 4X objective lens measured his field of view with a plastic ruler and found it to be 4 mm. He then placed some of his cheek cells on a slide, found them using the 4X objective lens and switched to the 40X objective lens. He counted twelve cells, side by side, that stretched from one side of the field of view to the other. What is the best estimate for the diameter of a cheek cell?
0.033 mm
0.132 mm
0.0132 mm
0.0033 mm

17. In fruit flies, the gray body color is dominant to the black, and long wings are dominant to short. If you crossed a gray, short-winged fly to a black, long-winged fly and got 25 percent gray, long wing; 25 percent gray, short wing; 25 percent black, short wing; and 25 percent black, long wing, what were the genotypes of the parental flies?
Ggll and GgLl
Ggll and ggLl
GGll and ggLl
GGll and GgLl

18. Which of the following statements about mitochondria is (are) true?
Mitochondria exist in all eukaryotes
Mitochondria exist in bacteria and plants
Mitochondria exist in animals, plants, and fungi
Both (A) and (C) are true

19. The flowing cytoplasm of an active amoeba is
propelled by microfilaments for lipid synthesis
an adaptation for extracellular digestion
composed of microtubules and extracellular matrix
dependent on microfilaments for intracellular circulation

20. In the earthworm, the efficiency of food absorption is increased by the presence of
the liver, which stores extra food in addition to making metabolic enzymes
the cecum, which stores unsuitable intake for excretion
infolds, which add surface area to the intestine
malphigian tubules, which increase the density of the food

21. A consensus sequence is associated with __________, while a signal sequence is part of __________.
translation, hnRNAs
DNA, translation
transcription, a snurp
spliceosomes, translation

22. One would expect to find steroid hormone receptors in the
plasma membrane
endoplasmic reticulum
nucleus
cytosol

23. Select the correct order of events in a persons response to a bacterial infection:
macrophage ingestion – Helper T cell activation – B cell activation – clonal formation
clonal formation – Helper T cell activation – B cell activation – macrophage ingestion
macrophage ingestion – B cell activation – T helper cell activation – clonal formation
Helper T cell activation – B cell activation – macrophage ingestion – clonal formation

24. People who have an extra X chromosome could have gotten it through
non-disjunction
transposition
transduction
crossing over

25. The HIV virus infects mostly
complement cells
red blood cells
T-killer cells
T-helper cells

26. Which of the following functions can be attributed to DNA polymerase?
It replaces RNA nucleotides with DNA nucleotides
It fixes errors in the replication of DNA
It ads nucleotides to the growing chain at the 3? end
All of the above are true

27. During translation, the first amino acid
occupies the aminyl site first, then the peptidyl site
occupies the aminyl site before the attachment of the large portion of the ribosome
of the polypeptide chain is methionine
all of the above

28. A signal sequence
is a sequence of DNA that begins transcription
is a sequence of RNA that is spliced out in the nucleus
is a sequence of DNA that directs a protein to certain organelles
is a sequence of DNA that attracts transcription factors

29. Northern blotting is used with
DNA
RNA
hnRNA
ssDNA

30. One would expect to find reverse transcriptase in
the plasmids of competent cells
retrovisuses
purple sulfur bacteria
archaebacteria

31. The target tissue for parathyroid hormone is (are) the
kidneys
bones
small intestine
all of the above

32. The products of oxidative phosphorylation are
oxygen and water
NADH and ATP
water and ATP
pyruvate and NADPH

33. A major difference between gram positive and gram negative bacteria is that the former has
a liposaccharide outer covering with a small peptidoglycan component in the cell wall
a small peptidoglycan component covering a large liposaccharide base
a large peptidoglycan component in the cell wall
a cell wall composed of liposaccharide and chitin

34. Let X represent an atom and X* its radioactive isotope. Assume both are taken up by living organisms. If the half-life of X* is 4,000 years, how much X* will be present in the remains of an organism that is 16,000 years old
as much as a living organism
4 times as much
one-fourth as much
one-sixteenth

35. All of our cells contain protooncogenes that may turn into oncogenes, which are cancer genes. The best explanation for protooncogenes is that they
came into our cells from a viral infection of our ancestors
arose from plasmids that have been inserted into bacteria and now reside in us
are DNA junk with no known function
help regulate cell division

36. In genetic engineering, it is necessary to cut DNA out of bacteria and eukaryotes. To insert the human insulin gene into a bacteria, one should use
two different restriction enzymes so that the pieces would not reanneal
the same restriction enzyme so that both pieces will have the same sticky ends
methylated bacterial DNA so that only some of it will be spliced
two different ligases to reanneal the DNA

37. Watson and Crick used all of the following information in elucidating the physical structure of DNA EXCEPT
the Meselson-Stahl experiment
X-ray crystallography
Chargoffs rules
the different sizes of purines and pyrimidines

38. Which of the following organelles is out of order from an endomembrane point of view?
nucleus
vesicles
golgi apparatus
endoplasmic reticulum

39. The products of the light reactions, or photophosphorylation, in photosynthesis are
oxygen and water
oxygen and ATP
oxygen, ATP, and NADPH
water, ATP, and NADPH

40. __________ refers to one gene affecting many traits.
Polygenesis
Pleiotropy
Linkage
Epistasis

41. Which of the following blood types are possible if the parents are A and O blood types?
A and O
B and O
AB only
O only

42. The portion of the DNA molecule that can vary is its
sugar
base
deoxyribose
ribose

43. An mRNA is 429 nucleotides long. The number of amino acids in the polypeptide chain formed from this mRNA is
143
142
141
429

44. Which of the following is NOT consistent with Griffith�s experiments?
injected mixture of R-strain and live S-strain: mouse dies
injected S-strain: mouse dies
injected heat-killed S-strain: mouse lives
injected mixture of heat-killed S-strain and live R-strain: mouse lives

45. Which of the following is a semi-conservative process?
DNA replication
non-disjunction
translation
transcription

46. Which of the following is true about enzymes?
They always work alone
They are consumed in a reaction
They are amino acid polymers
They always require a coenzyme

47. Which of the following has a vitamin as a building block?
apoenzyme
alloenzyme
metallic ion
coenzyme

48. Which enzyme would the microbes in the gut of a termite need to have in order to metabolize the cell walls of the wood that termites eat?
cellulase
esterase
protease
pepsin

49. The reds, oranges, and yellows of the leaves of deciduous trees that become evident in the fall are from
carotenoids
ATP
leaf decay
chlorophylls

50. Which of the following base substitution mutations in the mRNA above would have the least effect on the resulting polypeptide?
substitution of UCC for UUC in Phe
substitution of CAA for CCA in Pro
substitution of CAC for CAG in Gln
substitution of GGA for GGU in Gly