<span>Cross bridges are created when myosin heads bind to ATP. This phenomenon is basically muscle contraction at work. In order for myosin heads to be bound with ATP at the actin active site, it must be excited with Calcium.
Once myosin heads bind with ATP, it begins to slide and perform muscle contractions in the body, allowing a person to move.</span>
A single random allele from each pair of parent alleles will be passed on to the gamete.
1) RNA polymerase finds the promoter sequence on DNA.
2)RNA polymerase reads the DNA and builds complementary sequence.
3) Intron séquences are spliced out and exons are joined together.
4) The ends of the mature transcript are protected before it leaves the nucleus.
5) The mRNA attachés to the ribosome.
6) transfer RNA arrives at the ribosome and the anticodon complements to the mRNA codon.
7)amino acids form peptide bonds as tRNA molecules match the mRNA.
Answer:
Two European men and two Polynesian women settled on a previously uninhabited tropical island. All four of the settlers have brown eyes, a dominant trait, but one of the Europeans is heterozygous and carries the recessive gene for blue eyes. No new settlers arrive,and nobody leaves the island.After a few generations,the percentage of blue-eyed individuals increases from the original zero to 25 percent.This is probably due to which of the following factors?
genetic drift
Explanation:
Genetic drift entails when there are changes in the gene frequency which occur in a gene that is existing. From the analogy above, it is a known fact that only gneetic drift could allow such to happen as mutation will only occur with a sudden change of gene which is not the case described above
Answer:
d. more permeable to sodium ions.
Explanation:
The binding of Acetylcholine with the receptors at motor end plate facilitate membrane permeability to sodium ions therefore opening of voltage gated channels for sodium ions.
Sodium ions diffused into the synapse of post synaptic neuron at the neuromuscular junction.
If the stimulus is up to threshold levels; more chemical(neurotransmitter) gated sodium channels opens, and sodium ions move into the synapse to depolarize the membrane with reversal of charges to generate action potential.
The continuous binding of Acetycholine , leads to permanent opening of sodium ions,and over excitation from depolarization. Acetycholinesterase enzymes breakdown Acetycholine to choline and Acetyl Co -A. These are recycle back to Acetycholiine
