Answer:
Biogeochemical cycle is one of the several natural cycles, in which conserved matter moves through biotic and abiotic parts of a ecosystem. In biology, conserved matter refers to the finite amount of matter, in the forms of atoms, that present within the earth.
Explanation: It is true that the chemical is one of the natural cycles within earth
Answer:
The nucleotide sequence of a corresponding DNA strand would be TCGAATTCG.
It can be explained with the help of complementary base-pairing nature of the DNA strands that is, the nucleotide bases of the two strands are complementary in nature.
The purines (adenine and guanine) always base-pair with pyrimidines (thymine and cytosine).
More specifically, adenine always base-pair with thymine with the help of two hydrogen bonds and guanine always base-pair with cytosine with the help of three hydrogen bonds.
Answer:
1 - Malaria
2- Typhoid fever and Tuberculosis
Explanation:
In case of malaria, the causal microorganism is Plasmodium falciparum, which target red blood cells of host. In humans who have defective sickle cell allele, have abnomral shaped red blood cells. So microorganism does not able to attach to abnormal shaped RBCs thus humans having sickle cell allele are more resistant to death caused by malaria.
In cystic fibrosis, mutation on that gene which encodes a protein known as cystic fibrosis transmembrane conductance regulator (CFTR).
Normally Salmonella typhi (bacteria responsible for typhoid fever) enters into intestinal cells by attaching with CFTR receptor. Carriers of cystic fibrosis mutant gene, have abnormal CFTR thus reduced rate of entry of bacteria into carriers.
Normally Mycobacterium tuberculosis (bacteria responsible for tuberculosis) adds sulfate in its cell walls. In carriers of cystic fibrosis, arylsulfatase B activity is reduced which incorporates sulfate. Thus reduced arylsulfatase activity makes bacteria unable to add sulfate in its cell walls thus decreases their virulence to carriers of cystic fibrosis.
