Test 3

Question 1

the molecule that controls the synthesis of proteins and copies itself for the next generation of cells

Answer 1

DNA

Question 2

The building block of nucleic acids is a

Answer 2

nucleotide

Question 3

the four nitrogen bases that are found in the different nucleotides of DNA are

Answer 3

adenine, guanine, thymine, and cytosine

Question 4

the DNA nitrogen bases that are pyrimidines are

Answer 4

thymine and cytosine

Question 5

the DNA nitrogen bases that are purines are

Answer 5

adenine and guanine

Question 6

pyrimidine bases have

Answer 6

a single ring structure

Question 7

purine bases have

Answer 7

a double ring structure

Question 8

the _______ of an organism is all of its genetic material

Answer 8

genome

Question 9

in eukaryotic cells DNA is found in the

Answer 9

nucleus, mitochondria, and chloroplasts

Question 10

the number of chromosomes in humans is

Answer 10

46 or 23 pairs

Question 11

______ and ______ containing groups would not be found in a molecule of DNA

Answer 11

ribose and sulfur

Question 12

a sequence of DNA nucleotides coding for a specific protein or RNA molecule is a

Answer 12

gene

Question 13

the enzyme that unwinds DNA is

Answer 13

helicase

Question 14

the enzyme that joins Okazaki fragments is

Answer 14

ligase

Question 15

the enzyme that builds a short complimentary piece of RNA at the start of each DNA segment to be replicated is

Answer 15

primase

Question 16

the enzyme that adds nucleotides to form new strands of DNA is

Answer 16

DNA polymerase

Question 17

_______ is also called programmed cell death

Answer 17

apoptosis

Question 18

examples of the benefits of apoptosis include

Answer 18

formation of toes during embryonic development, the elimination of cells in the tail of a tadpole as the tadpole develops into a frog, and the elimination of sun burnt skin cells that might otherwise become cancerous

Question 19

before a cell divides, it must first

Answer 19

duplicate its entire genome

Question 20

a discreet package of DNA and associated proteins in eukaryotes is a

Answer 20

chromosome

Question 21

a _______ consists of a stretch of DNA and histones

Answer 21

nucleosome

Question 22

_______ chromosomes become microscopically visible before cell division because they become more tightly wound

Answer 22

eukaryotic

Question 23

one of two identical attached copies of a replicated chromosome is a

Answer 23

chromatid

Question 24

______ _______ are genetically identical and attached to each other

Answer 24

sister chromatids

Question 25

a cell with two full sets of chromosomes would be described as a

Answer 25

diploid cell

Question 26

a cell with one set of chromosomes would be termed a

Answer 26

haploid cell

Question 27

the process by which a sperm cell combines with an egg cell is

Answer 27

fertilization

Question 28

if a sperm cell combines with an egg the result is a

Answer 28

diploid cell

Question 29

mitosis is used for

Answer 29

repair of damaged cells, growth of an organism, asexual reproduction, and the production of genetically identical daughter cells

Question 30

_____ is a process used for production of gametes

Answer 30

meiosis

Question 31

immature cells that retain potential to develop into multiple cell types are

Answer 31

stem cells

Question 32

the process by which a bacterium uses a sex pilus to transfer genetic information to another bacterium is called

Answer 32

conjugation

Question 33

sexual reproduction is important to the survival of a species in a changing environment because

Answer 33

sexual reproduction produces genetically different individuals

Question 34

If an ecological disaster were to occur, some members of a ______ ______, _______ _____ population would have a greater chance at surviving than members of a _______ ______, _______ _______ population.

Answer 34

genetically diverse, sexually reproducing; genetically identical, asexually reproducing

Question 35

____ is an abbreviation for diploid

Answer 35

2n

Question 36

____ is an abbreviation for haploid

Answer 36

1n

Question 37

in humans, germ cells are located in

Answer 37

the testes and ovaries

Question 38

a _____ is the first diploid cell of a new organism

Answer 38

zygote

Question 39

______ cell division replicates a cell's DNA once and then divides twice

Answer 39

meiotic

Question 40

The human chromosomes that do not determine whether an individual is male or female are called ________

Answer 40

autosomes

Question 41

What is the chromosomal designation for human males?

Answer 41

XY

Question 42

What is the chromosomal designation for human females?

Answer 42

XX

Question 43

Chromosomes that look alike and carry the same sequence of genes for the same traits are

Answer 43

homologous chromosomes

Question 44

The __ chromosome is larger than the __ chromosome

Answer 44

X; Y

Question 45

If a person wanted to raise mules, they would need to mate

Answer 45

a male donkey with a female horse

Question 46

Can the hybrid germ cells of a mule undergo meiosis? Why?

Answer 46

no, because they have an odd number of chromosomes and chromosomes from the donkey cannot properly align with the chromosomes from the horse during prophase 1 of meiosis

Question 47

Sexual reproduction and meiosis generates genetic variety by

Answer 47

random fertilization, independent assortment, and crossing over

Question 48

the process by which homologous chromosomes exchange genetic material is known as

Answer 48

crossing over

Question 49

alternate forms of the same gene are called

Answer 49

alleles

Question 50

a gamete having more than one complete set of chromosomes is a

Answer 50

polyploid

Question 51

when chromosomes fail to separate at either first or second meiotic division this is called what? and what happens?

Answer 51

nondisjunction, and results in a sperm or egg cell with an abnormal number of chromosomes

Question 52

What can nondisjunction cause?

Answer 52

Trisomy 21, Turner Syndrome, Jacobs Syndrome, or Klinefelter Syndrome

Question 53

What causes down syndrome?

Answer 53

trisomy 21

Question 54

What are the results of down syndrome?

Answer 54

heart defects and mental impairment, and has an increased risk of occurring that is associated with the age of the mother

Question 55

A size ordered chart of the chromosomes of a fetus is called

Answer 55

a karyotype

Question 56

What is a karyotype used for?

Answer 56

to detect errors in meiosis, chromosomal abnormalities in a developing fetus, and to detect down syndrome

Question 57

_______ chromosomes have a mix of paternal and maternal alleles due to crossing over

Answer 57

recombinant

Question 58

Chromosomes retaining the allele combinations from each parent are

Answer 58

parental chromosomes

Question 59

to inherit an autosomal dominant disorder a person could receive the disease-causeing allele from

Answer 59

the mother or the father

Question 60

to inherit an autosomal recessive disorder requires a person to receive the disease-causing allele from

Answer 60

both parents

Question 61

if a person has a recessive allele for a disease and that allele is masked by a normal dominant allele, this person is termed

Answer 61

a carrier

Question 62

a male expresses _______ and ______ allele on his X chromosome

Answer 62

dominant and recessive