How many different gene combinations for sperm are possible for an organism with a genotype TtRr? a. 2 b. 4 c. 6 d. 10

B. 4

Explanation:

Based on the genotype of the organism illustrated (TtRr), the organism is a diploid organism i.e. organism with two sets of each chromosome. The number of possible combinations in the gamete can be calculated using the formula; 2^n where n = haploid number

In this case, the organism has a diploid number of 4. This means that the haploid number after meiotic division will be 2. Hence, the number of gene combinations will be 2² = 4 possible combinations.

"a.) well–developed vascular system."