BIO 120 TEST 3 QUESTIONS AND ANSWERS
ELABORATIONS!!
Queen Victoira of England was heterozygous (a carrier) for hemophilia, a sex-
linked (X-linked) recessive mutation. Her husband Prince Albert did not have
hemophilia. What was the chance for their child to be born sick with this disease?
(their youngest son, Prince Leopold of Albany, was indeed sick)
100%
75%
50%
25% 25%
Do a Punnet Square Bb x Bb
How many X-chromosomes does a human sperm cell have?
none
1
either 1 or none
46
23 Either 1 or none; sperm cells can either have an x-chromosome (resulting in
a female) or a y-chromosome (resulting in a male)
46 is the diploid number for human cells (number of chromosomes in somatic
cells)
23 is the haploid number for human cells (number of chromosomes in gametes)
, Only human egg cells can say they have 1 X-chromosome
How many X chromosoes does a human non-fertilized egg cell have?
none
1
either 1 or 2
46
20,000 1
Either 1 or 2 would be for a fertilized human egg cell
46 is the diploid number for human cells (number of chromosomes in somatic
cells)
20,000 are the number of protein coding genes in humans
In a human male, the Y-chomosome:
is inherited from mother
is inherited from father
can be inherited from either parent
is absent Is inherited from father
Mothers cannot pass on a Y-chromosome
The Y-chromosome is absent in human females
In somatic cells of a human female,
ELABORATIONS!!
Queen Victoira of England was heterozygous (a carrier) for hemophilia, a sex-
linked (X-linked) recessive mutation. Her husband Prince Albert did not have
hemophilia. What was the chance for their child to be born sick with this disease?
(their youngest son, Prince Leopold of Albany, was indeed sick)
100%
75%
50%
25% 25%
Do a Punnet Square Bb x Bb
How many X-chromosomes does a human sperm cell have?
none
1
either 1 or none
46
23 Either 1 or none; sperm cells can either have an x-chromosome (resulting in
a female) or a y-chromosome (resulting in a male)
46 is the diploid number for human cells (number of chromosomes in somatic
cells)
23 is the haploid number for human cells (number of chromosomes in gametes)
, Only human egg cells can say they have 1 X-chromosome
How many X chromosoes does a human non-fertilized egg cell have?
none
1
either 1 or 2
46
20,000 1
Either 1 or 2 would be for a fertilized human egg cell
46 is the diploid number for human cells (number of chromosomes in somatic
cells)
20,000 are the number of protein coding genes in humans
In a human male, the Y-chomosome:
is inherited from mother
is inherited from father
can be inherited from either parent
is absent Is inherited from father
Mothers cannot pass on a Y-chromosome
The Y-chromosome is absent in human females
In somatic cells of a human female,
