<u>Answer:</u>
<em>It is advantageous to have lesser number of bones in the pectoral girdle.</em>
<u>Explanation:</u>
Pectoral girdle is made up by the bones that connect the upper limbs to the appendicular skeleton which includes all the limb bones. Pectoral girdle in humans is made up of two bones. They are clavicle (collar bone) and scapula. The pectoral girdle allows the free movement of upper limbs.
The bones of pectoral girdle are not as massive as the bones of pelvic girdle since it doesn’t have the function of support. Lesser number of bones in pectoral girdle makes movement of upper limbs more free.
Answer:
B. there were more double crossovers in the progeny than would be expected based on probability
Explanation:
Crossing over or recombination can be defined as the exchange of genetic material between homologous chromosomes during meiosis. Moreover, the coefficient of coincidence is the number of double recombinants found in the progeny. The coefficient of coincidence can be estimated by the following equation:
Coefficient of coincidence (COC) = ADRF / EDRF
where ADRF = Actual Double Recombinant Frequency
and EDRF = Expected Double Recombinant Frequency
In the case above described, ADFR is higher than EDRF, and therefore COC will be higher than 1.