Excitation-contraction coupling refers to the series of events that begins with the excitation of the sarcolemma in response to stimulation by a neurotransmitter, and results in the release of calcium ions from the sarcoplasmic reticulum.
Hence, option D is the 1st process that starts the excitation-contraction coupling.
A mutation is a permanent change in the DNA sequence of a gene. This can be beneficial if the change gives a new function to or improves the function of that gene.
<span>The above is a definition. But one must really define "beneficial". Some regard it as beneficial if it helps the specific individual who has it. Others would think it beneficial if it produced some survival advantage that insured more descendents for that individual. </span>
<span>It is the difference between a mutation that allowed for greater athletic ability, but a decreased desire for offspring, versus a more moderate athletic enhancement, but a greater desire for offspring. </span>
<span>The small percentage of ways to improve an organism, versus the near infinite ways of harming the organism, mean that most mutations are not going to be beneficial. At best, they will be "inconsequential" - such as a new shade of eye color, or a mole on a section of your skin. </span>
The populist notion of "powers" that can come from mutations is wildly inaccurate. Even assuming a minor power like the ability to see infra red radiation would take thousands upon thousands of mutations over vast amounts of time. A mutation for blindness is far more likely.
<span>It should also be noted that the traditional model of evolutionary theory no longer applies to man. We don't allow changes in our environment, and without such changes, there is no need for one trait more than another to predominate. After all, it is irrelevent that a mutation might allow for greater speed in running, when everyone drives a car.</span>
It indicates what elements is composed by and how many atoms of one element are linked to the other.
For example, this is the formula for table salt is:
NaCl
The formula indicates that table salt (sodium chloride) is composed by sodium (Na) and chlorine (Cl) on a 1:1 ratio.
Hope it helped,
BioTeacher101
<span>Sam, a mendalien with black eyes and green skin, has a parent with orange eyes and white skin. Sam has a dominant phenotype expressed but he has a parent with a recessive phenotype which means he has a heterozygote gene.
Carole is a mendalien with orange eyes and white skin. Since Carole express both recessive phenotypes she should be homozygote recessive.
The key to this problem is how Sam dominant gene will be inherited. Since there are two heterozygote genes, it will be 50% dominant gene inherited for each phenotype. Then the result should be:
25% Dominant + Dominant =</span>black eyes and green skin<span>
25% Dominant + Recessive =</span>black eyes and white skin
25% Recessive + Dominant =orange eyes and green skin
25% Recessive + Recessive =orange eyes and white skin
Answer:
Enzyme Activity- Responsible reactions Enzyme catalyze nearby substrates
Cell to Cell Recognition- Recognize molecules on surface of the other cells
Cell Signalling- A chemical messenger that binds a membrane protein causing to change shape and relay the message inside a cell.
Transport materials- Provides channels for a certain solutes to pass through membrane