Answer:
9:3:3:1
Explanation:
If alleles of two genes separate randomly during anaphase-I of meiosis, some new combinations of the alleles are formed in the gametes. A heterozygous genotype for two loci (let's support TtRr) produces a total of four types of gametes in 1:1:1:1 ratio (TR, Tr, tR, and tr). The random fusion of these gametes from two double heterozygous parents (TtRr x TtRr) gives a phenotype ratio of 9:3:3:1. Here, 9/16 F2 progeny exhibit dominant phenotype for both loci while 1/16 exhibits recessive phenotype for both the genes. Rest 3/16 and 3/16 F2 progeny express dominant trait for one gene and recessive for the other.
In the large rainfall is some water remains in the top of the soil the rest of this water is seeped into the ground.
<u>Explanation:</u>
- Mainly the absorption of water by the ground depends upon the nature and the fertility of the soil.
- When the ground receives the water it mainly accounts for the absorption and then there will be a runoff. The absorption helps to raise the level of groundwater for future usage.
- The amount of water that can get into the soil mainly depends upon the permeability of the soil surface. The water which can't infiltrate in the soil runs off into the water bodies.
- The water is an essential requirement for survival and the existence of biological organisms.
Stem cells are what allow planaria to grow and regenerate as the stem cells can change into any of the cells that make up the planaria.
Answer: People who have received radiation treatment are 15 times more likely to develop benign thyroid tumors relative to does who have not.
Explanation:
Relative risk of benign thyroid tumor = (52/2872)/(6/5055)
= 0.018/0.0012
= 15