Answer:
<u>Genes </u>are units of <u>inheritance </u>that are found on <u>chromosomes</u>
Answer:
The animals present body structure is due to evolution. It is seen in each part including the structure of the heart. The vertebrate heart becomes complex from a simpler form.
Invertebrates, the heart of fishes is two-chambered having one auricle and one ventricle. The deoxygenated blood gets purified in the gills. They are aquatic and no lungs for breathing. The hearts pump a mixture of oxygenated and deoxygenated blood to the body.
The amphibians and reptiles have 3 chambered heart as they lead terrestrial mode of life. The gills modified into the lungs. The left auricle receives pure blood and the right auricle receives deoxygenated blood. The blood purified in the lungs and in the ventricle, both types of blood get a mix. The ventricle pumps the mixed-blood throughout the body.
In the case of birds and mammal, the heart is 4 chambered and the oxygenated and deoxygenated blood are separated. These two are higher vertebrates. No mix of pure and impure blood, the body receives only the oxygenated blood.
This shows to construct the phylogenetic tree of vertebrates - the fishes should be in the bottom, and above it amphibians, reptiles, then, mammals and birds on the top branch of the tree. As the chambers and structure of the hearts modified one after another.
I think d but im not sure
Answer:
none of the males or females could be colorblind, assuming that this question is referring to x-linked recessive inheritance patterns.
Explanation:
if it is an x linked recessive trait, then the male's genotype is, with (b) representing colorblindness and (B) representing normal vision. the female, who is h o m o z y g o u s for normal vision, would have the genotype.
It would be impossible for the dad to pass on his colorblind gene to a son, because he can only pass a Y chromosome to the son. and a daughter would get the colorblind gene, but the normal gene donated by the mom would dominate it so the daughter could not actually be colorblind