Alleles are the alternative form of a gene that code for a given trait, the alleles may be dominant or recessive or exhibit incomplete dominance. When two alleles are similar they are referred to as homozygous while they are not similar they are referred to as heterozygous. Based on the founder effect, rare alleles and combinations may be improved in new populations because of the reduced size of the initial population.
Answer:
D
Explanation:
there are around as many bacteria cells as there are human cells in the human body.
Answer: Autonomic: Acting or occurring involuntarily, without conscious control. Central nervous system: The part of the peripheral nervous system that transmits signals from the central nervous system to skeletal muscles, and from receptors of external stimuli, thereby mediating sight, hearing, and touch.
Explanation:
Answer:
d.The wing-assisted incline running theory postulates that wings were initially used to maintain balance while climbing up slopes.
Explanation:
Two theories were given to explain the origin of avian flight. The top-down theory suggested that the birds' ancestors were tree dwelling species. They took help of wings to glide from tree to tree in order to avoid predator or catch prey. The bottom up theory suggested that the birds' ancestors were ground dwelling species. They took help of wings to maintain a balance and provide a lift for efficient running.
Wing-assisted incline running was a mixture of both the above theories and gave a balanced view point. According to it, birds' ancestors used wings to maintain a balance while running up inclined slopes. The wings helped them to save energy while scaling slopes and eventually a flight mechanism was also developed.
Technically, the black widow spider is the deadliest spider despite it's size, due to it's overwhelmingly potent venom, which can and will kill a human if no medical attention is sought out for the person bit.