問題一覧
1
purple coloration in flowers, hairlessness in cats, and abnormal shape in enzymes are all examples of
phenotype
2
How many copies of each chromosome are in a single human gamete?
1
3
How many copies of chromosome 14 do your egg or sperm cells contain
1
4
How many copies of chromosome 14 do your muscle cells contain?
2
5
In what stage of meiosis do homologous chromosomes seperate?
meiosis I
6
What results from meiosis?
decrease in number of chromosomes in daughter cells (compared to parent cells) and increase in genetic diversity of gametes
7
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%
8
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
9
a red flower is crossed with a white flower, and all the seeds result in pink flowers. This is an example of
incomplete dominance
10
what human chromosome usually does not exchange DNA during meiosis?
Y chromosome
11
Which resource(s) is(are) used to examine inheritance over generations in human?
a pedigree chart
12
Why are X-linked traits more commonly expressed in males?
all of these
13
XXX, XYY, and XXY conditions are the result of:
an error during meiosis
14
the SRY gene on the Y chromosome is responsible for
testes development
15
the sex chromosomes found in a typical male are:
XY
16
humns have how many autosomes?
22 pairs
17
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%
18
two normal individuals have a child who has cystic fibrosis, an autosomal recessive disease. What were the chances of this?
1:4 chance
19
what describes a genotype that is heterozygous for a single trait?
Aa
20
crossing over occurs between
homologous chromosomes
21
how many chromosomes do human sperm and egg cells have?
23
22
a human female has how many pairs of homologous chromsomes?
23
23
a human male has how many pairs of homologous chromosomes?
22
24
how many alleles for a single trait are present in each human cell?
2
25
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
26
is a change in nucleotide sequence always detrimental?
no, it can also be beneficial or neutral (i.e. no effect)
27
In a population of 25 mice, how many total alleles are in the gene pool (for a particular gene)?
50
28
Which population is more likely to persist in the face of enviornmental change? (2 of 2)
population B