Answer:
B. In an area where a glacier has retreated
Explanation:
Primary succession, starts at a lifeless area where it has been affected by lava flood and/or retreated glacier therefore the answer is B.
Answer:
prenatal environments
Explanation:
Depending on the number of fertilized eggs and when the zygote division occurs, there are different types of twins. For example, If the zygote is formed by the union of an ovule and a sperm that after fertilization is divided to create two embryos, they are born identical twins, these babies carry the same genetic information.
The phenotype is - 75 % red and 25 %brown.
The genotype is hRhR - 25%
hBkhR - 50%
hBrhBk - 25%.
<h3><u>Explanation:</u></h3>
The cross given here is a simple dominant - recessive relationship between the three types of alleles of hair colour. The genes of this characteristics are present in autosomes, so will be segregated equally among all the sexes of the offsprings.
Now the genotype of auburn and red with black mother is given. So during gametogenesis, the gametes from the parents will be
Father - hBr and hR
Mother - hBk and hR
So, the probable combinations are hBrhBk, hBrhR and hBkhR.
The frequency of the combinations are 25%, 25% and 50% respectively.
The phenotypic ratio will be red : brown as 3:1.
When carbon is exchanged along the biosphere
The smallest type of stream is a brook.
