Archive for September 2017

Crenation is likely to occur in ________.

Naim 02:50

Crenation is likely to occur in ________. 




A) blood cells in an isotonic solution
B) blood cells in a hypotonic solution
C) blood cells in a hypertonic solution
D) blood cells in blood plasma




Answer: C

Extracellular matrix is ________.

Naim 02:49

Extracellular matrix is ________. 




A) composed of strands of actin protein
B) the most abundant extracellular material
C) a type of impermeable cell junction found in epithelia
D) not present in connective tissue



Answer: B

A gene can best be defined as ________.

Naim 02:49

A gene can best be defined as ________. 




A) a three-base triplet that specifies a particular amino acid
B) noncoding segments of DNA up to 100,000 nucleotides long
C) a segment of DNA that carries the instructions for one polypeptide chain
D) an RNA messenger that codes for a particular polypeptide


Answer: C

The functions of centrioles include ________.

Naim 02:49

The functions of centrioles include ________. 




A) organizing the mitotic spindle in cell division
B) providing a whiplike beating motion to move substances along cell surfaces
C) serving as the site for ribosomal RNA synthesis
D) producing ATP



Answer: A

The endomembrane system is ________.

Naim 02:49

The endomembrane system is ________. 



A) a system by which cells are riveted together by desmosomes
B) an interactive system of organelles whose membranes are physically or functionally connected
C) the process by which bacteria took up residence in ancient cells
D) a system of hydrophilic lipid monolayers that surround many cell organelles



Answer: B

Lysosomes ________.

Naim 02:48

Lysosomes ________. 



A) are always used for the cell to "commit suicide"
B) contain acid hydrolases that are potentially dangerous to the cell
C) maintain a highly alkaline internal environment
D) are the major site of protein synthesis




Answer: B

Which of the following statements is most correct regarding the intracellular chemical signals known as "second messengers"?

Naim 02:47

Which of the following statements is most correct regarding the intracellular chemical signals known as "second messengers"? 



A) Second messengers act through receptors called K-proteins.
B) Second messengers usually inactivate protein kinase enzymes.
C) Cyclic AMP and calcium may be second messengers.
D) Second messengers usually act to remove nitric oxide (NO) from the cell.



Answer: C

Which of the following is a principle of the fluid mosaic model of cell membrane structure?

Naim 02:47

Which of the following is a principle of the fluid mosaic model of cell membrane structure? 




A) Phospholipids form a bilayer that is largely impermeable to water-soluble molecules.
B) Phospholipids consist of a polar head and a nonpolar tail made of three fatty acid chains.
C) The lipid bilayer is a solid at body temperature, thus protecting the cell.
D) All proteins associated with the cell membrane are contained in a fluid layer on the outside of the cell.




Answer: A

Cells are composed mainly of ________.

Naim 02:47

Cells are composed mainly of ________. 




A) carbon, potassium, sodium, nitrogen
B) carbon, sodium, nitrogen, calcium
C) calcium, oxygen, sodium, potassium
D) carbon, hydrogen, nitrogen, oxygen



Answer: D

Which of the following is a concept of the cell theory?

Naim 02:46

Which of the following is a concept of the cell theory? 



A) Simple cells can arise spontaneously from rotting vegetation.
B) A cell is the basic structural and functional unit of living organisms.
C) The subcellular organelle is the basic unit of life.
D) Only higher organisms are composed of cells.



Answer: B

In the maintenance of the cell resting membrane potential ________.

Naim 02:46

In the maintenance of the cell resting membrane potential ________. 





A) extracellular sodium levels are high
B) cells are more permeable to Na+ than K+
C) the steady state involves only passive processes in all cells
D) the inside of the cell is positive relative to its outside


Answer: A

Which statement is the most correct regarding transcription/translation?

Naim 02:46

Which statement is the most correct regarding transcription/translation? 





A) The nucleotide sequence in a mRNA codon is an exact copy of the DNA triplet that coded for it.
B) The nucleotide sequence in a mRNA codon is an exact copy of the DNA triplet that coded for it except that uracil is substituted for thymine.
C) The nucleotide sequence in a tRNA anticodon is an exact copy of the DNA triplet that coded for it.
D) The nucleotide sequence in a tRNA anticodon is an exact copy of the DNA triplet that coded for it except that uracil is substituted for thymine.


Answer: D

DNA replication ________.

Naim 02:46

DNA replication ________. 



A) can also be called mitosis
B) is spontaneous, not requiring enzyme action
C) takes place during interphase of the cell cycle
D) occurs only in translationally active areas



Answer: C

Peroxisomes ________.

Naim 02:45

Peroxisomes ________. 



A) also called microbodies, contain acid hydrolases
B) are able to detoxify substances by enzymatic action
C) function to digest particles ingested by endocytosis
D) sometimes function as secretory vesicles




Answer: B

Ribosomes, endoplasmic reticulum, and the Golgi apparatus functionally act in sequence to synthesize and modify proteins for secretory use (export) only, never for use by the cell. This statement is ________.

Naim 02:45

Ribosomes, endoplasmic reticulum, and the Golgi apparatus functionally act in sequence to synthesize and modify proteins for secretory use (export) only, never for use by the cell. This statement is ________. 




A) false; proteins thus manufactured are for use inside the cell only
B) false; integral cell membrane proteins are also synthesized this way
C) false; lipids, not proteins, are synthesized this way
D) true


Answer: B

Mitochondria ________.

Naim 02:45

Mitochondria ________. 



A) are always the same shape
B) are single-membrane structures involved in the breakdown of ATP
C) contain some of the DNA and RNA code necessary for their own function
D) synthesize proteins for use outside the cell



Answer: C

Passive membrane transport processes include ________.

Naim 02:44

Passive membrane transport processes include ________. 



A) movement of a substance down its concentration gradient
B) movement of water from an area of low concentration to an area of high concentration
C) consumption of ATP
D) the use of transport proteins when moving substances from areas of low to high concentration



Answer: A

Phospholipids ________.

Naim 02:44

Phospholipids ________. 



A) are exclusively hydrophilic molecules
B) contain polar tails and nonpolar head groups
C) are both hydrophilic and hydrophobic in nature
D) form the lipid bilayer, with tails directed to the outside



Answer: C

Which of the following is true regarding cells in humans?

Naim 02:44

Which of the following is true regarding cells in humans? 




A) Organelles are independent life forms.
B) Maximum cell diameter is limited to 2 micrometers.
C) Cells can be as long as 1 meter.
D) All cells of an adult have a very short life span.



Answer: C

Hyperplasia means __________.

Naim 02:43

Hyperplasia means __________. 



A) programmed cell death
B) abnormalities in cell structure
C) a condition where the cell overproduces "cell glue"
D) accelerated growth




Answer: D

Mitosis ________.

Naim 02:40

Mitosis ________. 



A) is the formation of sex cells
B) produces nucleus replication
C) creates diversity in genetic potential
D) always results in division of a cell



Answer: B

Which of the following statements is correct regarding RNA?

Naim 02:40

Which of the following statements is correct regarding RNA? 




A) Messenger RNA, transfer RNA, and ribosomal RNA play a role in protein synthesis.
B) If the base sequence of DNA is ATTGCA, the messenger RNA template will be UCCAGU.
C) There is exactly one specific type of mRNA for each amino acid.
D) rRNA is always attached to the rough ER.



Answer: A

Once solid material is phagocytized and taken into a vacuole, which of the following statements best describes what happens?

Naim 02:39

Once solid material is phagocytized and taken into a vacuole, which of the following statements best describes what happens? 




A) A ribosome enters the vacuole and uses the amino acids in the "invader" to form new protein.
B) A lysosome combines with the vacuole and digests the enclosed solid material.
C) The vacuole remains separated from the cytoplasm and the solid material persists unchanged.
D) Nitrogen enters the vacuole and "burns" the enclosed solid material.



Answer: B

If cells are placed in a hypertonic solution containing a solute to which the membrane is impermeable, what could happen?

Naim 02:39

If cells are placed in a hypertonic solution containing a solute to which the membrane is impermeable, what could happen? 




A) The cells will swell and ultimately burst.
B) The cells will lose water and shrink.
C) The cells will shrink at first, but will later reach equilibrium with the surrounding solution and return to their original condition.
D) The cells will show no change due to diffusion of both solute and solvent.



Answer: B

Which of the following statements is correct regarding diffusion?

Naim 02:38

Which of the following statements is correct regarding diffusion? 



A) The rate of diffusion is independent of temperature.
B) The greater the concentration of gradient, the faster the rate of diffusion.
C) Molecular weight of a substance does not affect the rate of diffusion.
D) The lower the temperature, the faster the diffusion rate.



Answer: B

Which of these is not a function of the plasma membrane?

Naim 02:37

Which of these is not a function of the plasma membrane? 



A) It is selectively permeable.
B) It prevents potassium ions from leaking out and sodium ions from crossing into the cell.
C) It acts as a site of cell-to-cell interaction and recognition.
D) It encloses the cell contents.




Answer: B

The plasma membrane is ________.

Naim 02:37

The plasma membrane is ________. 




A) a single-layered membrane that surrounds the nucleus of the cell
B) a double layer of protein enclosing the plasma
C) the phospholipid bilayer surrounding the cell
D) a membrane composed of tiny shelves or cristae




Answer: C

Transcytosis is ________.

Naim 02:36

Transcytosis is ________. 



A) combining an endosome with a lysosome and degrading or releasing the contents
B) transporting an endosome from one side of a cell to the other and releasing the contents by exocytosis
C) recycling the contents of the endosome back to the surface of the cell
D) storing the contents of the endosome



Answer: B

Which of the following is true regarding the generation of a membrane potential?

Naim 02:36

Which of the following is true regarding the generation of a membrane potential? 



A) Both potassium and sodium ions can "leak" through the cell membrane due to diffusion.
B) In the polarized state, sodium and potassium ion concentrations are in static equilibrium.
C) The maintenance of the potential is based exclusively on diffusion processes.
D) When the sodium-potassium pump is activated, potassium is pumped into the cell twice as fast as the sodium is pumped out, thus causing the membrane potential.



Answer: A

Overfishing of the western bluefin tuna in the Gulf of Mexico breeding ground resulted in a serious decline in the population. Fishing quotas were established in the Gulf of Mexico to allow the endangered population to recover. Why did this policy fail to achieve the desired result?

Naim 22:17

Overfishing of the western bluefin tuna in the Gulf of Mexico breeding ground resulted in a serious decline in the population. Fishing quotas were established in the Gulf of Mexico to allow the endangered population to recover. Why did this policy fail to achieve the desired result?



a. The feeding grounds of the western bluefin are geographically separated from the feeding grounds of the eastern bluefin.
b. The breeding grounds of the western bluefin are geographically separated from the breeding grounds of the eastern bluefin.
c. Fisherman disregarded the policy.
d. Western and eastern populations of bluefin feed throughout the entire North Atlantic.
e. The policy was designed without advice and guidance from scientists.




Answer: D

Which of the following questions cannot be answered by means of the hypothetico-deductive method?

Naim 22:17

Which of the following questions cannot be answered by means of the hypothetico-deductive method?




a. Are bees more attracted to red roses than to yellow roses?
b. Are red roses more beautiful than yellow roses?
c. Why are red roses red?
d. Do red roses bloom earlier than yellow roses?
e. Are red roses more susceptible to mildew than yellow roses?37. Which of the following questions cannot be answered by means of the hypothetico-deductive method?



Answer: B

Which of the following statements about the experiments of Tyrone Hayes on abnormalities of male frog sex organs is correct?

Naim 22:16

Which of the following statements about the experiments of Tyrone Hayes on abnormalities of male frog sex organs is correct?




a. In a set of controlled experiments, he had to reject his hypothesis that atrazine was causing abnormalities in male frogs.
b. As a result of the comparative experiments, he formed a new hypothesis that snails were causing the limb deformities in the frogs.
c. The controlled experiments compared the effects of various atrazine concentrations on reproductive tissues.
d. He reasoned, by means of inductive logic, that if atrazine caused abnormal testes development, then such deformities could be caused simply by exposing developing tadpoles to various concentrations of atrazine.
e. The abnormality rate was proportional to the level of atrazine exposure.




Answer: C

Which of the following statements represents a scientific point of view?

Naim 22:16

Which of the following statements represents a scientific point of view?



a. Earth was created by a supernatural force.
b. The positions of the sun, moon, and stars provide guidance for making decisions.
c. Inner strength comes from the beauty in nature.
d. Testing the effect of antibiotics on E. coli can help prevent deaths from food poisoning.
e. Meditation helps to solve problems.




Answer: D

Comparative experiments are designed to answer questions that require

Naim 22:16

Comparative experiments are designed to answer questions that require





a. observation and comparison rather than controlled variables.
b. experimental groups and control groups.
c. little or no data collection.
d. a final, definitive answer.
e. the collection of qualitative data.


Answer: A

Which of the following statements is false?

Naim 22:15

Which of the following statements is false?





a. Statistical methods are applied to data in order to calculate the likelihood that the null hypothesis is incorrect.
b. Statistical tests analyze variation and calculate the probability that observed differences in an experiment could be due to random variation.
c. Statistical tests can be used to evaluate both comparative and controlled experiments.
d. Scientists generally conclude that the differences they measure are true if the statistical tests show that the probability of error is 5 percent or lower.
e. The power of science derives from absolute dependence on evidence that comes from reproducible and quantifiable observations.



Answer: D

The advantage of controlled experiments is that

Naim 22:15

The advantage of controlled experiments is that




a. all variables are held constant except for one.
b. the hypothesis is proven right.
c. patterns can be predicted.
d. investigations can be carried out in the field.
e. a massive amount of data can be synthesized.



Answer: A

Which of the following statements about the scientific method is correct?

Naim 22:15

Which of the following statements about the scientific method is correct?




a. Deductive logic is used to make predictions from a hypothesis.
b. The most informative experiments are those that have the ability to show that a hypothesis is correct.
c. In a comparative experiment, a scientist compares groups that differ in a variable that has been manipulated in one of the groups and left unaltered in the other group.
d. Controlled experiments are valuable when we do not know or cannot control the critical variables.
e. A statistical test of a hypothesis starts with the premise that a significant difference exists between the groups in the study.




Answer: A

Which of the following is not a feature of scientific hypotheses?

Naim 22:15

Which of the following is not a feature of scientific hypotheses?



a. They are unable to be falsified.
b. They make predictions.
c. They are based on observations.
d. They can be tested by experimentation.
e. They can be tested by observational analysis.



Answer: A

The main purpose of any single experiment is to

Naim 22:14

The main purpose of any single experiment is to




a. obtain accurate quantitative measurements.
b. prove unambiguously that a particular hypothesis is correct.
c. avoid comparative analysis.
d. answer as many key questions as possible.
e. test a prediction that is based on a hypothesis.


Answer: E

Which of the following can result from a scientific investigation?

Naim 22:14

Which of the following can result from a scientific investigation?




a. Proof of the hypothesis
b. Refinement of the experimental design
c. Formulation of new questions that result in additional experimentation
d. Repetition of statistical tests to verify results
e. Development of additional technologies to meet the needs of scientists



Answer: C

A phylogenetic tree

Naim 22:13

A phylogenetic tree



a. shows evolutionary relationships.
b. relies on evidence from fossils, metabolic processes, and molecular analyses of genomes.
c. helps us understand the history and relationships of living organisms.
d. shows the order in which populations split and evolved into new species.
e. All of the above




Answer: E

Plants are

Naim 22:11

Plants are



a. eukaryotic multicellular autotrophs.
b. eukaryotic unicellular autotrophs.
c. eukaryotic multicellular heterotrophs.
d. prokaryotic multicellular autotrophs.
e. prokaryotic unicellular heterotrophs.



Answer: A

Plants, fungi, and animals have evolved from

Naim 22:11

Plants, fungi, and animals have evolved from



a. protists.
b. endosymbiotic bacteria.
c. Archaea.
d. cyanobacteria.
e. inorganic molecules.




Answer: A

Ozone is important to life on Earth because it

Naim 22:10

Ozone is important to life on Earth because it



a. is toxic to all forms of life.
b. can be used in place of oxygen.
c. blocks much ultraviolet radiation.
d. provides energy to some basic forms of life.
e. acts as a disinfectant.




Answer: C

Metabolism is

Naim 22:09

Metabolism is




a. the consumption of energy only.
b. the release of energy only.
c. all conversions of matter and energy taking place in an organism.
d. the production of heat by chemical reactions.
e. the exchange of nutrients and waste products with the environment.



Answer: C

Yeasts can be used to study human cancer because yeasts and humans

Naim 22:08

Yeasts can be used to study human cancer because yeasts and humans




a. share a genetic code.
b. are both prokaryotes.
c. have exactly the same genome.
d. have the same number of chromosomes.
e. None of the above; yeast cannot be used to study human cancer.



Answer: A

Which of the following represents a correct ordering of the levels of complexity at which life is studied, from most simple to most complex?

Naim 22:08

Which of the following represents a correct ordering of the levels of complexity at which life is studied, from most simple to most complex?



a. Cell, tissue, organ, organism, population, community
b. Community, population, organism, organ, tissue, cell
c. Cell, organ, tissue, organism, population, community
d. Cell, tissue, organ, population, organism, community
e. Tissue, organ, cell, population, organism, community




Answer: A

Which of the following statements is true?

Naim 22:07

Which of the following statements is true?



a. The diversity of life has depended on similar environments and ecological communities throughout the globe.
b. Sexual selection and genetic drift contribute to the diversity of life.
c. Earth has existed and changed over a few thousand years, at most.
d. All ancestral forms of life were very similar to organisms that currently exist.
e. All organisms are genetically closely related.




Answer: B

A key point in Darwin's explanation of evolution is that

Naim 22:07

A key point in Darwin's explanation of evolution is that




a. the biological structures most likely to be inherited are those that have become best suited to the environment through constant use.
b. all mutations that occur are those that will help future generations better fit into their environments.
c. any trait that confers even a small increase in the probability that its possessor will survive and reproduce will be strongly favored and will spread through the population.
d. genes change in order to help organisms cope with problems encountered within their environments.
e. extinction is nature's way of weeding out undeserving organisms.


Answer: C

Based on the large numbers of offspring produced by many organisms, Darwin proposed that mortality was high and only a few individuals survived to reproduce. He referred to the differential reproductive success of individuals with particular variations as

Naim 22:07

Based on the large numbers of offspring produced by many organisms, Darwin proposed that mortality was high and only a few individuals survived to reproduce. He referred to the differential reproductive success of individuals with particular variations as




a. evolution.
b. artificial selection.
c. the cell theory.
d. natural selection.
e. inheritance of acquired characteristics.


Answer: D

A species consists of

Naim 22:07

A species consists of



a. all the organisms that live together in a particular area.
b. morphologically similar organisms that cannot interbreed.
c. morphologically similar organisms capable of interbreeding.
d. an adult organism and all of its offspring.
e. morphologically similar organisms that live in the same area.




Answer: C

A cell

Naim 22:06

A cell



a. can be composed of many types of tissues.
b. is found only in plants and animals.
c. is the smallest entity studied by biologists.
d. may be a distinct entity or a building block of a more complex organism.
e. All of the above




Answer: D
Subscribe to: Posts (Atom)