Answer:
Option (a).
Explanation:
Phylogentic tree may be defined as the the diagrammatic representation of the evolutionary relationship of the organism. The phylogenetic trees are made on the hypothesis and do not explain any fact.
The branching in the phylogenetic tree determines the evolution of the species from the common ancestor. The common ancestor is located at the base of the phylogenetic tress. Since, Ardipithecus ramidus is located at the base it shows that Ardipithecus ramidus is a common ancestor.
Thus, the correct answer is option (a).
Blood typing is an example of codominance
Answer:
c. because arteries carry high pressure blood from the heart
Explanation:
Arteries carry the oxygenated blood that is pumped directly from the left ventricle of the heart. Since they receive blood from the heart, the blood pressure is higher in arteries than veins. To withstand the higher pressure of blood pumped by heart, arteries have thicker walls than the walls of veins.
Answer:
True
Explanation:
Adenine and Guanine fall under the category of Purine nitrogenous base. Purine is made of six member pyrimidine ring fused to five member imidazole ring. It is water soluble in nature.
A purine always pairs with a pyrimidine base to form a DNA base pair. Thymine and Cytosine are the two pyrimidine bases. Adenine bonds with Thymine by forming two hydrogen bonds and Guanine is bonded to Cytosine via three hydrogen bonds. When a purine base is formed it self inhibits formation of more purine and also activates formation of pyrimidine base. Hence, amount of purine and pyrimidine are almost equal in cell.