Answer:
Natural Selection is an evolutionary process that caused the increment of dark-coloured Biston betularia moths in England. It happened due to increase of air pollution in the industries. The bark of the trees became darker because of the deposition of pollutants.
In order to save itself from predators, the species of Biston betularia evolved itself to a dark coloured species so that the predators gets confused between the bark of the tree and the Biston betularia.
Answer:
Power stroke (myosin head bends) coupled with the release of ADP and phosphate
Explanation:
Muscle contraction results from myosin heads adhering to actin and attracting it inwards. It uses ATP. Myosin adhers to actin at a binding site of its globular actin protein and adheres at another binding site for ATP (hydrolyzed ATP to ADP, Pi and energy)
ATP binding prompts myosin to detach from actin, ATP is changed to ADP and inorganic phosphate, Pi by ATPase. The energy formed at this process orientates myosin head to a “cocked” direction.
The myosin head goes in the direction of the M line, holding the actin with it in the process causing the filaments to orientate nearly 10 nm in the direction of the M line--- power stroke (force is produced), the sarcomere reduces in length and the muscle contracts.
Note: The power stroke is seen when ADP and phosphate disattaches itself from the myosin head.
At the terminal point of the power stroke, the myosin head as low-energy, followed by ADP release.
The attached image shows the cross-bridge muscle contraction cycle, which is activated by Ca2+ sticking to the actin active site. And how actin moves in relation to myosin.
Type two is where their are to much insulin but not enough glucose that's all I can say sorry
Answer:
The statement suggests ability of existing DNA molecule to replicate itself by the process of DNA replication. Each strand of double helical DNA can serve as template for the synthesis of new complementary DNA strand.
Explanation:
Watson and Crick proposed the double-helical structure of DNA. Accordingly, the DNA molecule is a double helical structure in which two polynucleotide chains are held together by base pairing between the complementary bases of two chains.
There are four nitrogenous bases present in DNA: adenine and guanine (purines) and cytosine and thymine (pyrimidines). Adenine always pairs with thymine and cytosine pairs with guanine base.
According to Watson and Crick, the ability of one DNA strand to base-pair with a complementary DNA strand suggests the existence of the DNA replication process. During DNA replication, each DNA strand should serve as a template to specify the nucleotide sequence of the new DNA strand.