BIOLOGY TEST 5

black fur in mice (B) is completely dominant to brown fur (b). short tails (T) are completely dominant to long tails (t). What fraction of the progency of the cross BbTt x BBtt will have black fur and long tails?

1/2

If the liver cells of an animal have 40 chromosomes, how many chromosomes does its sperm cells have?

20

a woman w/ a color blind father and a normal man have children. what is the probability that a son of theirs will be color blind?

50%

if the recombination frequency for genes 1 and 2 was found to be 50% this would mean that

A and C ( genes 1 and 2 are unlinked & genes 1 and 2 are on different chromosomes

a man is brought to court in a paternity case. he has blood type B. the mother has blood type B. which blood type of a child wuld exclude the accused from paternity?

A and C (blood type AB and A)

b/w which two genes would you expect the highest frequency of recombination

A and G (the furthest away from one another)

In pea plants, purple flower color is dominant to white flower color. If 2 pea plants that are true breeding for purple flowers are closed in the offspring.

A. all of the flowers are purple

X-linked recessive traits in humans are observed ______.

A. in more males than females

The observable trait expressed by an organism are described as it's _____.

A. phenotype

centromeres of sister chromatids uncouple and chromatids separate

Anaphase II

Check phone

B. 1/4

A couple who are both of the gene for cystic fibrosis have 2 children who have cystic fibrosis. What is the probability that their next child will have cystic fibrosis?

B. 25%

Barring in chickens is due to a sex-linked dominant gene (B). The sex of chicks at hatching is difficult to determine, but barred chicks can be distinguished from non barred at that time. To use the trait so that at the hatching all chicks of one sex are barred, what cross would you make?

B. barred males x nonbarred females

A recessive trait will be observed in individual that are _____ for that trait.

C. Homozygous

Meiosis produces ______ daughter cells

C. four haploid

An achondroplastic dwarf man with normal vision marries a color-blind women of normal height. The man's father was six feet tall, and both the women's parents were of average height. Achondroplastic dwarfism is autosomal dominant, and red-green color blindness is X linked recessive. How many of their male children would be color-blind and normal height?

C. half

What is the probability that individual C-1 is Ww?

D. 1

A women with type B blood and a Man with type A blood could have children with which of the following phenotypes?

D. A, B, AB, or O

Test Cross

D. All correct

Which of the following traits shows a polygenic method of inheritance?

D. Height in humans

Pea plants were well suited for Mendel's breeding experiments for all of the following reasons except.

D. Peas have a particularly long generations time C9 months like humans)

A mother with type B blood has 2 children one with type A blood and one with type O blood. Her husband has type O blood. Which of the following could you conclude from this information?

D. The husband could be the father of the child with type O blood, not type A

How do cells at the completion of meiosis compare with cells that have replicated their DNA and are just about to begin meiosis?

D. They have half the number of chromosomes and 1/4 the amount of DNA

A man brought to court in a paternity case. He has blood type B. The mother has blood type B which blood type of a child would exclude the accuse from paternity?

D. both a and c

In cats, black color is caused by an X-linked all the other allele at this locus causes orange coloring. What kinds of offspring would expect from the cross?

D. tortoiseshell female; black male

a sexually reproducing animal has two unlinked genes one for head shape (H) and one for tail length (T) its genotype is HhTt. according to the law of segregation, which of the following genotypes is possible in a gamate form this organism?

HT

Tetrads of chromosomes are aligned at the center of the cell; independent assortment soon follows....

Metaphase I

synapsis of homologous pairs occurs in crossing over; crossing over occurs in....

Prophase I

when studying meiosis in a newly discovered animal species, you notice that there are no chiasmate seen during meiosis. what implications does this have on the genetic diversity of this organism?

There will be less diversity in the organism b/c chiasmata are necessary for crossing over

what is a karyotype

a display of every pair of homologous chromosomes with in a cell, organized according to size and shape

what is the difference b/w a monohybrid cross and a dihybrid cross?

a monohybrid cross tracks inheritance of one character. a dihybrid cross tracks the inheritance of two characters

a man who carries an X-linked allele will pass it on to.....

all of his daughters

in what phase of meiosis does the segregation of alleles occur?

anaphaseI

if a non-disjunction event occurs in meiosis and the resulting gamate is used for fertilization then the offspring would be __________, b/c they have an abnormal number of chromosomes

aneuploid

recombination of linked genes is a result of

crossing over

in corn plants, a dominant allele I inhibits kernal color white the recessive allele i permits color when homozygous. at different locus the dominant gene P causes purple kernal color while the homozygous recessive genotype pp causes red kernals. if plants are heterozygous at both loci are crossed, the phenotype ration will be 9 purple, 3 red and 4 white

epistasis

is the following statement true or false: "all of the eggs of one human female are genetically identical"

false

in animals, somatic cells are produced by mitosis and _________ are produced by meiosis

gametes

a 40% frequency of recombination is observed in....

in genes located very far apart from one another on the same chromosome

when the phenotypic of the heterozygous is intermediate to the phenotypes of both homozygotes, the gene displays_______

incomplete dominace

in what phase of meiosis does independent assortment of alleles for different genes occurs?

metaphase I

the i gene for a particular protein on human red blood cells has 3 forms: I^A, I^B and i. this is an example of

multiple alleles

____________ referes to the ability of a single gene to have multiple pheotypic effects

pleiotropy

a trait that is determined by more than one gene is considered __________

polygenic

in cattle, roan coat color (mixed red and white hairs) occurs in the heterozygous (Rr) offspring of red (RR) and white (rr) homozygotes. when 2 roan cattle are crossed, the phenotypes of the progeny are found to be in the ratio on 1 red: 2 roan: 1 white. which of the following crosses could produce the highest percentage roan cattle

red x white

2 plants are crossed, resulting in offspring with a 3:1 ratio fro a particular trait. This suggests...

that the parents were both heterzygous

centromeres uncouple and chromatids are separated from each other

the statement is true for mitosis and meiosis II

a cell divides to produce two daughter cells that are genetically identical

the statement is true for mitosis only

independent assortment of chromosomes occurs

the statement occurs in Meiosis I

how do cells at the completion of the meiosis compare with cells that have replicated their dna and are just about to begin meiosis?

they have half the number of chromosomes and 1/4 the amount of dna

to express the symptoms of a recessively inherited disorder (to express a recessive phenotype) an individual would have to inherit ___________ recessive alleles

two