Answer:
A. pH
Explanation:
Denaturation of proteins is a protein whereby the protein molecule loses its primary structure and ultimately its physical functioning as a result of factors including pH, temperature or concentration of chemicals. Based on this definition, it is visible that denaturation of proteins can be caused by these three factors: pH, chemical and temperature.
However, in this case of PEPSIN enzyme, which is a proteinous molecule produced in the stomach of humans and functions in breaking down proteins, its denaturation occurs as it moves along the digestive tract to the intestines. This is as a result of the changes in pH in the digestive tract.
The pH of the stomach where pepsin is produced is acidic i.e. <3.0. However, as one moves towards the intestine, the pH increases, which is unfavorable or considered harsh for the pepsin enzyme. Hence, it gets denatured.
Answer:
pollen is important in fertilization because pollen carries male gamete and it helps in transportation of male gamete during fertilization in mainly gymnosperms and angiosperms.
Answer: The calcium ion binds to troponin, and this slides the tropomyosin rods away from the binding sites.
Explanation:
Contraction and relaxation of muscle cells brings about movements of the body. The contractile myofilament called sarcomeres are bounded at each end by a dense stripe called the Z - line, to which the myosin fibres are attached, and lying in the middle of the sarcomere are the actin filaments, overlapping with the myosin.
When action potential spreads from the nerve along the sarcolemma (muscle cell membrane), it penetrates deep into the muscle cell through the sarcoplasm (cytoplasm of muscle cell), and releases CALCIUM from the intracellular stores.CALCIUM triggers the binding of myosin to the actin filament next to it forming CROSS BRIDGES.
For this to occur, ACTIN BINDING SITE has to be made available. TROPOMYOSIN is a protein that winds around the chains of the actin filament and covers the myosin-binding sites to prevent actin from binding to myosin. The first step in the process of contraction is for calcium ions to bind to troponin so that tropomyosin can slide away from the binding sites on the actin strands.
The answer is B . Neutrons are found in nucleus
Answer:
Attached to each sugar is one of four bases--adenine (A), cytosine (C), guanine (G), or thymine (T). The two strands are held together by hydrogen bonds between the bases, with adenine forming a base pair with thymine, and cytosine forming a base pair with guanine.
Explanation:
