問題一覧
1
purple coloration in flowers, hairlessness in cats, and abnormal shape in enzymes are all examples of
phenotype
2
What results from meiosis?
decrease in number of chromosomes in daughter cells (compared to parent cells) and increase in genetic diversity of gametes
3
the SRY gene on the Y chromosome is responsible for
testes development
4
how many chromosomes do human sperm and egg cells have?
23
5
How many copies of chromosome 14 do your muscle cells contain?
2
6
what human chromosome usually does not exchange DNA during meiosis?
Y chromosome
7
what describes a genotype that is heterozygous for a single trait?
Aa
8
the sex chromosomes found in a typical male are:
XY
9
lactose intolerance results when a person inherits two defective alleles for the lactase gene. Normally this gene produces the enzyme lactase, which breaks down lactose during digestion. What would MOST likely happen if a person had one defective allele and that allele was functional?
the person would digest less lactose than normal
10
In a population of 25 mice, how many total alleles are in the gene pool (for a particular gene)?
50
11
Hair texture is an example of incomplete dominance. A person who is homozygous dominant HH has curly hair, and that person mates with someone who has straight hair (homozygous recessive; hh) What percentage of their offspring will have straight hair?
0%
12
Which resource(s) is(are) used to examine inheritance over generations in human?
a pedigree chart
13
Which population is more likely to persist in the face of enviornmental change? (2 of 2)
population B
14
Why are X-linked traits more commonly expressed in males?
all of these
15
A gene has alleles X, Y, and Z, which are codominant alleles. An individual that is homozygous X is crossed with an individual that is homozygous Z. What phenotypes will the offspring of this cross express?
a phenotypes of X and Z, equally
16
one parent has one copy of a dominant allele for Gene 87 and one recessive allele for Gene 87. The other parent has two copies one dominant allele for Gene 87. What is the chance that their children will inherit the recessive condition.
0%
17
How many copies of chromosome 14 do your egg or sperm cells contain
1
18
a red flower is crossed with a white flower, and all the seeds result in pink flowers. This is an example of
incomplete dominance
19
is a change in nucleotide sequence always detrimental?
no, it can also be beneficial or neutral (i.e. no effect)
20
In what stage of meiosis do homologous chromosomes seperate?
meiosis I
21
two normal individuals have a child who has cystic fibrosis, an autosomal recessive disease. What were the chances of this?
1:4 chance
22
a human male has how many pairs of homologous chromosomes?
22
23
humns have how many autosomes?
22 pairs
24
XXX, XYY, and XXY conditions are the result of:
an error during meiosis
25
a human female has how many pairs of homologous chromsomes?
23
26
How many copies of each chromosome are in a single human gamete?
1
27
how many alleles for a single trait are present in each human cell?
2
28
crossing over occurs between
homologous chromosomes