Answer:DNA helicases are essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied. During DNA replication, DNA helicases unwind DNA at positions called origins where synthesis will be initiated.
Explanation:
A. Neurotransmitters diffuse across the membrane of neurons
Explanation:
When we begin to move, the brain initially sends a signal to the spinal cord, then the nerve cells in the spinal cord monitor the exact coordination of the muscles. Signal from the brain and the spinal cord directs the movement of leg muscles. Signal is transmitted by release of neurotransmitter from the neuron to the synaptic cleft and its binding to the receptor of adjacent neuron.
Answer:
1/4
Explanation:
The man is brown eyed so it can have both BB and Bb genotype but his mother was blue eyed and blue eyes is a recessive trait so his mother must have been bb. He would have got one "b" allele from her so his genotype must be Bb. Woman is also brown eyed with a blue type parent so her genotype must be Bb.
Bb X Bb :
B b
B BB Bb
b Bb bb
As evident, only 1/4 progeny will have recessive bb genotype which will result into blue eyes. So the probability that this couple will have a blue-eyed child is 1/4.