The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
The main function of the respiratory system is to allow the exchange of gases between the atmosphere and the lungs.
Hence,the only structure that carries out this function is the alveoli as other structures such as the nose,trachea and pharynx transport gases to the alveoli just so that it can can out its function.
Answer:
C
Explanation:
According to Newton's second law, when the same force is applied to two objects of different masses, a. the object with greater mass will experience a great acceleration and the object with less mass will experience an even greater acceleration.
Answer:
the answer is on letter B
Explanation:
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Answer:
D. Aa
Explanation:
Given:
Jill (mother) is heterozygous for gene A --------- i.e Jill = Aa
Jack (father) who is homozygous recessive for gene A-------- i.e Jack = aa
Now if both cross and fertilization occurs, we have:
A a
a Aa aa
a Aa aa
The offsprings are (Aa, Aa, aa, aa)
Nondsijunction is the inability of homologous chromosomes to seperate properly during cell division. Now, we were told that this fertilization undergone nondisjunction in meiosis 1. Hence, both homologous chromosome move into the same daughter cells instead of different daughter cells because separation of homologous chromosome does not occur properly.
Therefore the result of these fertilization of a normal haploid sperm with an egg that had undergone nondisjunction in meiosis yields offspring with genotype Aa of their Mother (Jill).
