Brown eyes are dominant to blue eyes. Assuming two heterozygous individuals are crossed together, what phenotype ratio would we expect from the offspring?
50% brown, 50% blue
75% brown, 25% blue
100% brown
75% blue, 25% brown
25
When does non-disjunction of chromosomes occur regarding chromosome disorders?
Cell growth
Mitosis
The cell cycle
Meiosis
25
In fruit flies, red eyes are dominant to white eyes. If a homozygous dominant fly is crossed with a homozygous recessive fly, what percentage of the offspring would have white eyes?
75%
25%
0%
50%
25
What type of mutation causes down syndrome?
An extra Y chromosome.
Non-disjunction in chromosome 23.
Non-disjunction in chromosome 21.
A point mutation in chromosome 21.
25
What happens during a silent mutation?
An amino acid is changed.
A stop codon is produced.
No amino acids are changed.
All amino acids are changed after that mutation.
25
What type and how many cells are produced in meiosis?
four diploid cells
Four haploid cells
two haploid cells
two diploid cells
25
A gene that is found on the X chromosome is a...
Dominant trait
Recessive trait
Sex-linked gene
Mendellian trait
25
The point where RNA polymerase binds and transcription takes place is in which part of the lac operon?
lacz,x,y
Promotor
Operator
CAP site
25
Which of the following are frameshift mutations?
Substitutions and deletions
Deletions and insertions
insertions
deletions
25
How many cells and what type are produced in Meiosis phase I?
Two genetically identical haploid cells.
Two genetically different diploid cells.
Two genetically different haploid cells.
Two genetically identical diploid cells.
25
What ratio of the offspring will be carriers given a homozygous dominant and a heterozygous parent?
1/2
1/4
1/3
25
What are the symptoms of the inherited disorder, hemophilia?
Abnormal redblood cell shape.
Blood that is unable to clot after injury.
Inability to distinguish between red and green.
Stunted/slowed limb growth.
25
Which structure is required for the lac operon?
Operator
All of these.
CAP site
Promotor
25
In which phases do the spindle fibers form during meiosis?
Prophase I and II
Proshpase I
Metaphase I and II
Metaphase II
25
Four' o' clock flowers come in three colours: Red, white (homozygous) and pink (heterozygous). What type of inheritance is this?