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