Answer:
Tt and tt
Explanation:
To solve this just work backwards. The first box has Tt so one parent has to have T and the other t. Since the tall plant is on the top, it is T_ and t_. Next use the second box (tt). They are both t so the final answer is Tt x tt.
Answer:
A
Explanation:
Earth revolves around the sun
I took a test on this
Answer:
The environment the moths lived in used to be unpolluted. This made dark moths rare. As the area where light moths were found became more polluted, the light moths became less common in the polluted/dark areas. Light Moths began to evolve after not being able to survive in dark forests, they began to get darker and blend in with the polluted area to be safe from predators.
Explanation:
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.
