wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

BIOL-112-Principles of Biology II- Chapters 8, 9, & 10: TYU

Total questions: 106

Worksheet time: 53mins

Name
Class
Date
1.

In photosynthesis, plants use carbon from _____ to make sugar & other organic molecules.

a)

the sun

b)

chlorophyll

c)

water

d)

soil

e)

carbon dioxide

2.

How does carbon dioxide enter the leaf?

a)

through the roots

b)

through the stomata

c)

through the chloroplasts

d)

through the vascular system

e)

through the thylakoids

3.

In a rosebush, speaking as specifically as possible, chlorophyll is located in _____.

a)

mesophyll cells, found within the thylakoids of a leaf's chloroplasts

b)

chloroplasts, which are in thylakoids in the mesophyll cells of a leaf

c)

thylakoids, which are in chloroplasts in the mesophyll cells of a leaf

d)

thylakoids, which are in mesophyll cells in the chloroplasts of a leaf

e)

chloroplasts, which are in mesophyll cells in the thylakoids of a leaf

4.

Chlorophyll molecules are in which part of the chloroplast?

a)

stroma

b)

thylakoid lumen

c)

plasma membrane

d)

thylakoid membrane

e)

stomata

5.

The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from __________.

a)

glucose

b)

water

c)

radioisotopes

d)

light

e)

carbon dioxide

6.

In photosynthesis, what is the fate of the oxygen atoms present in CO2? They end up __________.

a)

as molecular oxygen

b)

in water

c)

as molecular oxygen & in sugar molecules

d)

in sugar molecules & in water

e)

in sugar molecules

7.

The reactions of the Calvin cycle are not directly dependent on light, but they usually do not occur at night. Why?

a)

carbon dioxide concentrations decrease at night

b)

plants usually open their stomata at night

c)

it is often too cold at night for these reactions to take place

d)

at night, no water is available for the Calvin cycle

e)

the Calvin cycle requires products only produced when the photosystems are illuminated

8.

The Calvin cycle occurs in the __________.

a)

matrix

b)

stroma

c)

stomata

d)

thylakoid membrane

e)

thylakoid lumen

9.

A photon of which color would carry the most energy?

a)

red

b)

yellow

c)

green

d)

blue

e)

orange

10.

The most important role of pigments in photosynthesis is to __________.

a)

catalyze the synthesis of ATP

b)

capture light energy

c)

catalyze the hydrolysis of water

d)

store energy

e)

screen out harmful ultraviolet rays

11.

What range of wavelengths of light are absorbed by the pigments in the thylakoid membranes?

a)

the range absorbed by carotenoids

b)

the infrared

c)

green, which is why plants are green

d)

the entire spectrum of white light

e)

blue & red

12.

Based on the work of Engelmann, the wavelengths of light most effective in driving photosynthesis are referred to as __________.

a)

an absorption spectrum

b)

a visible light spectrum

c)

an effective spectrum

d)

an electromagnetic

e)

an action spectrum

13.

When chloroplast absorb light, _______.

a)

they become reduced

b)

their photons becomes excited

c)

the Calvin cycle is triggered

d)

their electrons become excited

e)

they lose potential energy

14.

What structure is formed by the reaction center, light-harvesting complexes, and primary electron acceptors located in the thylakoid membrane?

a)

the photosystem

b)

the fluorescence center

c)

the electron transport chain

d)

NADP+ reductase

e)

ATP synthase

15.

Where do the electrons entering photosystem II come from?

a)

chlorophyll molecules in the antenna complex

b)

the electron transport chain

c)

water

d)

light

e)

ATP

16.

During photosynthesis in chloroplasts, O2 is produced from __________ via a series of reactions associated with __________.

a)

H2O . . . photosystem I

b)

CO2 . . . photosystem II

c)

CO2 . . . the Calvin cycle

d)

H2O . . . photosystem II

e)

CO2 . . . both photosystem I & the Calvin cycle

17.

During photosynthesis, an electron transport chain is used to __________.

a)

transport electrons from photosystem II to photosystem I

b)

transport excited electrons from P680 to an electron acceptor

c)

transport excited electrons from P700 to an electron acceptor and transport excited electrons from P680 to an electron acceptor

d)

transport excited electrons from P700 to an electron acceptor

e)

transport NADPH from the light reactions to the Calvin cycle

18.

Both mitochondria and chloroplasts _______.

a)

are surrounded by a single membrane

b)

use chemiosmosis to produce ATP

c)

obtain electrons from water

d)

release oxygen as a by-product

e)

reduce NAD+, forming NADP

19.

You could distinguish a granum from a crista because the granum, but not the crista, would _______.

a)

be inside a mitochondrion

b)

have photosynthetic pigments

c)

contain protein but not lipids

d)

function in energy transformation

20.

During photosynthesis in a eukaryotic cell, an electrochemical gradient is formed across the _______.

a)

thylakoid membrane

b)

chloroplast outer membrane

c)

stomata

d)

chloroplast inner membrane

e)

cristae

21.

The light reactions of photosynthesis generate high-energy electrons, which end up in ____. The light reactions also produce ____ and ____.

a)

water . . . sugar . . . oxygen

b)

NADPH . . . ATP . . . oxygen

c)

chlorophyll . . . ATP . . . NADPH

d)

ATP . . . NADPH . . . oxygen

e)

oxygen . . . sugar . . . ATP

22.

The energy used to produce ATP in the light reactions of photosynthesis comes from ______.

a)

the oxidation of sugar molecules

b)

fluorescence

c)

carbon fixation

d)

splitting water

e)

movement of H+ through a membrane

23.

What is the role of NADP+ in photosynthesis?

a)

It is reduced and then carries electrons to the Calvin cycle.

b)

As part of the electron transport chain, it manufactures ATP.

c)

It assists chlorophyll in capturing light.

d)

As a component of photosystem II, it catalyzes the hydrolysis of water.

e)

It acts as the primary electron acceptor for the photosystems.

24.

Which choice occurs during the Calvin cycle?

a)

excited electrons are conveyed from chlorophyll to an electron acceptor

b)

CO2 is reduced

c)

photons are absorbed

d)

ATP & NADPH are synthesized

e)

light energy is converted to chemical energy

25.

Rubisco is _____.

a)

the 5-carbon sugar molecule that reacts with CO2 to begin the Calvin cycle

b)

the enzyme that forms a 4-carbon compound in CAM photosynthesis

c)

the enzyme responsible for splitting H2O to produce O2 in photosynthesis

d)

the enzyme in plants that first captures CO2 to begin the Calvin cycle and is the most abundant protein in chloroplasts

e)

the first stable intermediate in C4 photosynthesis

26.

In the Calvin cycle, CO2 is combined with _____.

a)

a 5-carbon compound to form an unstable 6-carbon compound, which decomposes into two 3-carbon compounds

b)

a 7-carbon compound to form two 4-carbon compounds

c)

a 2-carbon compound to form a 3-carbon compound

d)

two 2-carbon compounds to form a 5-carbon compound

e)

a 5-carbon compound to form a stable 6-carbon compound that can be converted directly to glucose

27.

Glyceraldehyde-3-phosphate (G3P) is produced in the stroma of chloroplasts. Which statement most completely describes this compound?

a)

It is produced from glucose during glycolysis.

b)

For every three molecules of CO2, six molecules of G3P are formed, but five molecules must be recycled to regenerate three molecules of RuBP

c)

For every three molecules of CO2, six molecules of G3P are formed, but only one molecule exits the cycle to be used by the plant cell.

d)

It is a 3-carbon sugar.

e)

All of the choices are correct.

28.

Which statement correctly describes the relationship between the light reactions and the Calvin cycle?

a)

The light reactions produce ATP and NADPH, both of which are used in the Calvin cycle.

b)

The light reactions produce water, ATP, NADPH, all of which are used in the Calvin cycle.

c)

The light reactions produce carbon dioxide and water, all of which are used in the Calvin cycle.

d)

The light reactions produce ADP and NADP+, both of which are used in the Calvin cycle.

e)

The light reactions produce carbon dioxide, ATP, NADPH, all of which are used in the Calvin cycle.

29.

What is the role of NADP+ in photosynthesis?

a)

It forms part of photosystem II.

b)

It absorbs light energy.

c)

It is the primary electron acceptor.

d)

It helps produce ATP from the light reactions.

e)

It forms NADPH to be used in the Calvin cycle.

30.

The use of C4 and non-CAM plants as crops may be limited in some regions because on hot, dry days, they close their stomata. What happens as a result of this closing?

a)

It builds up oxygen from the light reactions in the leaf.

b)

In a process called photorespiration, rubisco binds oxygen instead of carbon dioxide.

c)

It prevents carbon dioxide from entering the leaf.

d)

It reduces water loss.

e)

All of the choices are correct.

31.

Why are C4 plants more suited to hot climates than C3 plants?

a)

They do not close their stomata in hot, dry weather.

b)

They evolved in cold weather but migrated to the tropics, where they were more suitable.

c)

The same cells that bind carbon dioxide perform the Calvin cycle.

d)

Unlike C3 plants, they keep fixing carbon dioxide even when the concentration of carbon dioxide in the leaf is low.

e)

They suspend photosynthesis in the heat.

32.

You have a large, healthy philodendron that you carelessly leave in total darkness while you are away on vacation. You are surprised to find that it is still alive when you return. What has the plant been using for an energy source while in the dark?

a)

Even though it can't carry out the light reactions, the plant can still produce sugars because the Calvin cycle doesn't require light.

b)

While it did have access to light, the plant stored energy in the form of sugars or starch, and it was able to derive energy from the stored molecules during your vacation.

c)

When light energy is not available, plants can derive energy from inorganic molecules.

d)

Even though the plant received no visible light, it was able to use the short-wave part of the electromagnetic spectrum (gamma rays and X-rays) to carry out photosynthesis.

e)

None of the choice is correct.

33.

The person credited with first recognizing (in the 1850s) that living cells cannot arise spontaneously, but arise only from previously existing cells, is ______.

a)

Robert Hooke

b)

Watson

c)

Rudolf Virchow

d)

Louis Pasteur

e)

Anton van Leeuwenhoek

34.

The function of the cell cycle is to produce daughter cells that _____.

a)

are genetically identical to the parent cell (assuming no mutation has occurred)

b)

have the same number of chromatids as the parent cell had chromosomes

c)

have the same number of chromosomes as the parent cell but not the same genetic content

d)

have a random assortment of maternal and paternal chromosomes

e)

None of the choices is correct.

35.

The complex of DNA and protein that makes up a eukaryotic chromosome is properly called _____.

a)

a chromatid

b)

chromatin

c)

a centromere

d)

a chromoplast

e)

a centrosome

36.

How many maternal chromosomes are present in a somatic human cell not engaged in cell division?

a)

23

b)

46

c)

92

d)

184

e)

None of the choices is correct.

37.

A cell entering the cell cycle with 32 chromosomes will produce two daughter cells, each with _____.

a)

64 chromosomes

b)

64 pairs of chromosomes

c)

32 pairs of chromosomes

d)

16 chromosomes

e)

None of the choices is correct.

38.

Cytokinesis refers to ______.

a)

reduction in the number of chromosomes

b)

division of the entire cell

c)

division of the nucleus

d)

division of the cytoplasm

e)

movement of a cell from one place to another

39.

Chromatids are _____.

a)

found only in aberrant chromosomes

b)

the bacterial equivalent of eukaryotic chromosomes

c)

composed of RNA

d)

held together by the centrioles

e)

identical copies of each other if they are part of the same chromosome

40.

If a cell contains 60 chromatids at the start of mitosis, how many chromosomes will be found in each daughter cell at the completion of the cell cycle?

a)

15

b)

30

c)

45

d)

60

e)

120

41.

A biochemist measured the amount of DNA in cells growing in the laboratory and found that the quantity of DNA in the cells doubled _____.

a)

between prophase and anaphase of mitosis

b)

during the M phase of the cell cycle

c)

between the G2 phase and prophase

d)

between anaphase and telophase of mitosis

e)

between the G1 and G2 phases of interphase

42.

A cell biologist carefully measured the quantity of DNA in grasshopper cells growing in cell culture. Cells examined during the G2 phase of the cell cycle contained 200 units of DNA. What would be the amount of DNA at G1 of the cell cycle in one of the grasshopper daughter cells?

a)

50 units

b)

100 units

c)

between 50 and 100 units

d)

200 units

e)

400 units

43.

During interphase, the genetic material of a typical eukaryotic cell is ______.

a)

dispersed in the cytoplasm as long strands of chromatin

b)

condensed and the chromosomes are often visible under the light microscope

c)

transported through the nuclear pores

d)

attached to microtubule spindle fibers

e)

dispersed in the nucleus as long strands of chromatin

44.

DNA replication occurs in ______.

a)

the G1 phase of interphase in reproductive cells only

b)

metaphase of meiosis only

c)

the cytokinesis portion of the cell's life cycle

d)

the S phase of interphase in both somatic and reproductive cells

e)

prophase of both mitosis and meiosis

45.

If a normal somatic human cell is just about to divide, it has __ chromatids.

a)

0

b)

23

c)

46

d)

92

e)

There is not enough information to answer the question.

46.

Down syndrome is characterized by cells having three copies of chromosome 21. As a cell in an individual with Down syndrome prepares to enter mitosis, how many chromatids would be present?

a)

23

b)

46

c)

92

d)

94

e)

98

47.

Which of the following does not occur during mitosis?

a)

the movement of chromosomes to opposite poles

b)

separation of chromatids

c)

alignment of chromosomes along the cell's equator

d)

replication of chromosomes

e)

condensation of chromatin

48.

During which phase in the cell cycle would you find the most DNA per cell?

a)

prophase II

b)

S

c)

G2

d)

S1

e)

G1

49.

In telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in _____.

a)

interphase

b)

S phase

c)

anaphase

d)

metaphase

e)

prophase

50.

Which phase of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope?

a)

anaphase

b)

S phase

c)

interphase

d)

metaphase

e)

telophase

51.

Assume that you are dealing with a species that has 14 chromosomes per somatic cell. How many sister chromatids are present in early telophase of mitosis?

a)

0

b)

7

c)

14

d)

28

e)

None of the choices is correct.

52.

In a human skin cell that is going through the cell cycle, when do the centrosomes separate?

a)

prophase

b)

anaphase

c)

S phase

d)

metaphase

e)

G2 phase

53.

Following cytokinesis in an animal cell, how many centrioles does each new daughter cell possess?

a)

zero

b)

one

c)

two

d)

four

e)

eight

54.

Which represents an incorrect description?

a)

metaphase: the nuclear envelope disappears

b)

metaphase: chromosomes line up on the equatorial plane

c)

telophase: chromosomes become more extended

d)

anaphase: there is movement of the chromosomes to the poles

e)

prophase: chromosomes become more tightly coiled

55.

In animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle?

a)

prophase

b)

anaphase

c)

metaphase

d)

the G1 phase

e)

cytokinesis

56.

You would know a dividing cell was a plant cell rather than an animal cell if you saw that _____.

a)

it had formed a cell plate

b)

it had microtubules

c)

it had two pairs of centrioles during prophase

d)

the nucleolus was visible during metaphase

e)

it had formed a cleavage furrow

57.

Which process does not occur in dividing bacteria?

a)

mitosis

b)

replication of DNA

c)

inward growth of the plasma membrane

d)

separation of the origins of replication

e)

binary fission

58.

During binary fission in a bacterium _____.

a)

the two DNA molecules divide in half, forming four DNA fragments

b)

the two DNA molecules break up into plasmids

c)

the origins of replication move apart

d)

the two DNA molecules attach to the centrioles

e)

the two DNA molecules float free in the cell and are guided to daughter cells by a spindle-like apparatus

59.

Which is involved in the binary fission of bacteria?

a)

formation of a cell plate

b)

disintegration of the nuclear membrane

c)

formation of a spindle apparatus

d)

distribution of a copy of the single parental chromosome to each daughter cell

e)

prophase, prometaphase, metaphase, anaphase, and telophase

60.

When a cell in S phase is fused with a cell in G1, _____.

a)

the original G1 cell will divide immediately

b)

the two nuclei fuse and further division is arrested

c)

DNA synthesis begins immediately in the original G1nucleus

d)

the chromosomes of the original G1 nucleus condense in preparation for mitosis

e)

the replication of DNA occurring in the original S nucleus is terminated

61.

Tissue culture experiments with PDGF demonstrate that without this substance _____.

a)

fibroblasts fail to divide

b)

bacterial cells lose their resistance to antibiotics

c)

animal cells are unable to attach to the substratum

d)

the various kinases, such as MPF, are unable to bind to cyclin

e)

cells divide in an uncontrolled fashion, confirming PDGF’s role as a cell division inhibitor

62.

You would be unlikely to see which human cell dividing?

a)

skin cell

b)

nerve cell

c)

intestinal lining cell

d)

cell from an embryo

e)

cancer cell

63.

Observations of cancer cells in culture support the hypothesis that cancer cells _____.

a)

do not exhibit density-dependent inhibition

b)

spend the majority of their time in the G0 phase

c)

exhibit anchorage dependence

d)

produce molecules that inhibit the growth factors required for cell division

e)

All of the listed responses are correct.

64.

What is the difference between a benign tumor and a malignant tumor?

a)

Cells of benign tumors do not metastasize; those of malignant tumors do.

b)

Cells of benign tumors metastasize; those of malignant tumors do not.

c)

Benign tumors will not kill you; malignant tumors will.

d)

Benign tumors do not arise by transformation; malignant tumors do.

e)

Benign tumors arise by transformation; malignant tumors do not.

65.

How many genes are present in the human genome?

a)

23

b)

46

c)

hundreds

d)

tens of thousands

e)

almost one hundred thousand

66.

What is a locus?

a)

a type of spore made only by fungi

b)

the specific location of a gene along the length of a chromosome

c)

a structure that appears during prophase I and consists of two paired genes

d)

the precise DNA sequence of a gene

e)

a cell with two chromosome sets

67.

Sexual and asexual reproduction are alike in that _____.

a)

they both require meiosis to complete the reproductive cycle

b)

they both involve two parents

c)

they both give rise to genetically distinct offspring

d)

in both cases, every parent transmits all of its genes to its progeny

e)

they can both occur in multicellular organisms

68.

A clone is the product of _____.

a)

asexual reproduction

b)

sexual reproduction

c)

mitosis

d)

meiosis

69.

A karyotype is ______.

a)

a display of all of an individual's chromosomes arranged in pairs

b)

a list of all the genes a person carries

c)

a method of identifying crossover events

d)

the physical traits a person has

e)

all the possible gametes a person could produce

70.

Fertilization produces _____.

a)

a haploid zygote in some life cycles and a diploid zygote in others

b)

a diploid zygote

c)

a haploid zygote

d)

a multicellular haploid organism in a life cycle with an alternation of generations

e)

a diploid zygote, except during the gametophyte stage of alternation of generations

71.

Which statement is true?

a)

Haploid cells can divide by mitosis.

b)

Diploid cells can divide by mitosis.

c)

Haploid cells cannot divide by meiosis.

d)

Diploid cells can divide by meiosis.

e)

All of the choices are correct.

72.

Which is part of the alternation of generations life cycle?

a)

multicellular diploid stage (sporophyte)

b)

spores

c)

zygote

d)

multicellular haploid stage (gametophyte)

e)

All of the choices are correct.

73.

If the multicellular algal genus Ulva shows alternation of generations, it uses ____.

a)

only meiosis and fertilization

b)

mitosis only

c)

mitosis, meiosis, and fertilization

d)

both mitosis and meiosis but not fertilization

e)

both mitosis and fertilization but not meiosis

74.

In sexually reproducing species, the chromosome number remains stable over time because _____ and ____ always alternate.

a)

mitosis … fertilization

b)

meiosis I … meiosis II

c)

meiosis … interphase

d)

meiosis … fertilization

e)

meiosis … mitosis

75.

The egg (ovum) of a domesticated rabbit contains 22 chromosomes. How many chromosomes are in the somatic (body) cells of a rabbit?

a)

11

b)

22

c)

44

d)

88

e)

132

76.

In a diploid cell containing 10 chromosomes, meiosis results in the formation of daughter cells containing ______ chromosomes.

a)

0

b)

5

c)

10

d)

20

e)

40

77.

How many pairs of autosomes do humans have?

a)

23

b)

22

c)

2

d)

1

e)

It depends on the sex of the individual.

78.

Sister chromatids __________.

a)

are only involved in meiosis

b)

are only involved in mitosis

c)

have the same gene loci but may have different alleles of some genes

d)

are identical copies of each other formed during DNA synthesis

e)

are pairs of chromosomes, one of which comes from the father and one of which comes from the mother

79.

Humans have 46 chromosomes. This number of chromosomes will be found in ______.

a)

all gamete-producing cells after meiosis I

b)

liver cells

c)

all the egg and sperm cells

d)

all the cells found in a human

e)

all cells in anaphase of mitosis

80.

When we say that an organism is haploid, we mean that ______.

a)

its cells have half of one set of chromosomes

b)

its cells have two sets of chromosomes

c)

it has one half of a chromosome

d)

its cells each have one chromosome

e)

its cells have a single set of chromosomes

81.

Which is a function of mitosis in humans?

a)

production of eggs

b)

production of sperm

c)

increasing genetic variability

d)

decreasing the number of chromosomes

e)

multiplication of body cells that are genetically identical to the parent cell

82.

Somatic cells in humans contain _____ set(s) of chromosomes and are therefore termed ______.

a)

one … diploid

b)

two … diploid

c)

one … haploid

d)

two … haploid

e)

three … triploid

83.

Nearly all life cycles have both haploid and diploid phases. Usually, the transition from haploid to diploid takes place _____.

a)

at fertilization, when gametes fuse

b)

during gastrulation

c)

when mitotic cytokinesis occurs

d)

during crossing over in meiosis

e)

when DNA is replicated during the S phase of the cell cycle

84.

Spores and gametes are different in that _____.

a)

gametes are derived directly from sporophytes to form gametophytes

b)

gametes can fuse to form a zygote, but spores can develop into independent organisms without first forming a zygote

c)

gametes never resemble spores morphologically

d)

only the formation of gametes contributes to genetic variation

e)

gametes are always haploid, whereas spores are diploid

85.

Which result in cells that contain half the parental chromosome number?

a)

metaphase

b)

interphase

c)

mitosis

d)

meiosis

e)

cytokinesis

86.

At the end of telophase I of meiosis and the first cytokinesis, there are ______.

a)

two diploid cells

b)

one haploid ovum and three polar bodies

c)

four haploid cells

d)

two haploid cells

e)

four diploid cells

87.

What is the result when a diploid cell undergoes meiosis?

a)

two diploid cells

b)

four haploid cells

c)

two haploid cells

d)

four diploid cells

e)

two haploid cells and two diploid cells

88.

Synapsis occurs during _____.

a)

anaphase I

b)

metaphase I

c)

prophase II

d)

prophase I

e)

cytokinesis

89.

Which occur during anaphase II?

a)

Homologs separate and migrate toward opposite poles.

b)

Nuclei re-form.

c)

The synaptonemal complex disappears.

d)

Chromosomes line up in one plane.

e)

Sister chromatids separate and migrate toward opposite poles.

90.

Which occurs during anaphase I?

a)

Chromosomes line up in one plane.

b)

Homologs separate and migrate toward opposite poles, guided by the spindle apparatus.

c)

Sister chromatids separate and migrate toward opposite poles.

d)

Nuclei re-form.

e)

The cell is haploid.

91.

What is the function of meiosis?

a)

to make one cell with twice the number of chromosomes as the parent pairs

b)

to make diploid spores

c)

to make cells with a haploid number of chromosomes

d)

to make four cells with the same chromosome number as the parent

e)

to make exact copies of the parent cell

92.

Crossing over occurs during ______.

a)

prophase II

b)

prophase I

c)

metaphase II

d)

cytokinesis

e)

metaphase I

93.

Regions of chromosomes where nonsister chromatids cross over are called _____.

a)

inversions

b)

tetrads

c)

chiasmata

d)

homologs

e)

kinetochores

94.

The synaptonemal complex _____.

a)

is formed by a protein called cohesin

b)

physically connects homologous chromosomes during mitosis

c)

is another name for chiasmata

d)

is broken down by enzymes during anaphase II

e)

physically connects homologous chromosomes during prophase I

95.

Which event occurs only during prophase I of the first meiotic division?

a)

Homologous chromosomes line up at the center of the cell.

b)

The nuclear membrane breaks down.

c)

A spindle of microtubules forms.

d)

Replication of DNA takes place.

e)

Synapsis of homologous pairs occurs.

96.

In a male mammal, every cell that undergoes meiosis gives rise to ______ sperm.

a)

one

b)

two

c)

four

d)

no set number

e)

three or four

97.

Which function makes meiosis lengthier and more complex than mitosis?

a)

decreasing the chromosome number to haploid

b)

ensuring that each daughter cell gets a single, complete set of chromosomes

c)

introducing genetic variation among the daughter cells

d)

undergoing two rounds of cytokinesis

e)

All of the choices are correct.

98.

Regarding the role of cohesin protein in maintaining cohesion between sister chromatids, which of the following statements is false?

a)

During meiosis I, cohesin holds sister chromatids together along their lengths as chiasmata form between homologs.

b)

During meiosis II, cohesin holds sister chromatids along their lengths as the second meiotic spindle forms.

c)

Cleavage of cohesins between sister chromatid arms at anaphase I allows homologs to separate.

99.

Ignoring crossover, how many kinds of gametes can be produced by an organism with a diploid number of 8?

a)

2

b)

4

c)

8

d)

16

e)

32

100.

Which contributes to genetic variation in sexually reproducing species?

a)

random fertilization, DNA synthesis, independent assortment

b)

internal fertilization, spindle formation, crossing over

c)

crossing over, internal fertilization, independent assortment

d)

random fertilization, independent assortment, crossing over

e)

independent assortment, spindle formation, random fertilization

101.

In humans, the haploid number of chromosomes is 23. Independent assortment has the possibility of producing _____ different types of gametes.

a)

24

b)

232

c)

100,000

d)

1 million

e)

223

102.

The diploid number of chromosomes in a certain animal is 8 (2n = 8). How do the four pairs of homologous chromosomes align and separate during meiosis?

a)

All 16 chromatids move together.

b)

They align and assort independently to form any of 16 different combinations.

c)

The first to move influences all the others.

d)

Exactly two maternal and two paternal chromosomes always move to each of the two poles.

e)

All of the maternal chromosomes always move to one pole, and all the paternal chromosomes always move to the other pole.

103.

In a diploid set of chromosomes, one member of each pair of homologous chromosomes is derived from the father (paternal), and the other comes from the mother (maternal). If 2n = 6, what is the probability of obtaining a gamete in which all the chromosomes are paternal ones?

a)

1/4

b)

1/8

c)

1/16

d)

1/32

e)

The answer cannot be determined from these data.

104.

The major contribution of sex to evolution is that _____.

a)

it is the only mechanism for species to reproduce

b)

it increases genetic variation

c)

it provides a way in which somatic mutations can be inherited

105.

Which answer is not involved with or an outcome of crossing over?

a)

The DNA in two nonsister chromatids is broken by specific proteins at exact points.

b)

the random alignment of homologous pairs of chromosome at metaphase I

c)

Chiasmata indicate where crossing over is occurring between homologs.

d)

formation of chromosomes containing paternal and maternal alleles

e)

All of the choices relate to crossing over.

106.

Which statement reflects an advantage that sexual reproduction likely provides over asexual reproduction?

a)

Although both reproductive strategies perpetuate the same combination of alleles within individuals in a population, sexual reproduction is energetically less costly than asexual reproduction.

b)

Although energetically more costly than asexual reproduction, sexual reproduction leads to different combinations of alleles that could provide adaptability in a changing environment.

c)

Sexual reproduction maintains the same combination of alleles and does not run the risk of losing successful combination of alleles as is observed to occur in asexually reproducing organisms.

d)

In terms of energetic costs, sexual reproduction is a cheaper strategy than asexual reproduction for generating genetic variation in a population.

e)

Although sexual and asexual reproduction both offer opportunities for increasing genetic variation, sexual reproduction is comparatively lower in its energetic costs to the organism.