AP BIOLOGY

HEREDITY

MONOHYBRID CROSS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of the following represents a homozygous recessive individual?
A
DD
B
Dd
C
dd
Explanation: 

Detailed explanation-1: -Individuals who are homozygous dominant (DD) or heterozygous (Dd) are Rh+. Those who are homozygous recessive (dd) are Rh-(i.e., they do not have the key Rh antigens). Clinically, the Rh factor, like ABO factors, can lead to serious medical complications.

Detailed explanation-2: -Homozygous condition means that both the alleles are same. E.g., RR and rr. They can be of two types: homozygous dominant (e.g. RR) or homozygous recessive (e.g. rr).

Detailed explanation-3: -Background: The DD genotype gene is a linkage marker for an etiologic mutation at or near the angiotensin-converting enzyme gene and has been associated with increased risk for the development of coronary artery disease, left ventricular hypertrophy and left ventricular dilation after myocardial infarction.

Detailed explanation-4: -Homozygous recessive is a term used to describe an organism that carries two identical copies of the recessive gene.

There is 1 question to complete.