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.
1. Filament
2. Anther
3. Petal
4. Stigma
5. Style
6. Ovary
7. Sepals
8. Stem
Answer:
The correct answer is
Option C. Season.
Explanation:
Jupiter has no seasons, while Uranus, with a spin axis tiled 98 degrees, has the most extreme ones. Tilting of planets are responsible for season. If there is very low tilting, the seasons are not present. In jupiter the tilting is very low that is 3 degree so that's why jupiter has no seasons. In earth, the seasons are present due to high tilting i. e. 23 degree.
Secondary since plants/animals already lived there, but got killed/driven out of the area they lived/thrived in/on.
Structure and function-there are only TWO types of cells-prokaryotic and eukaryotic
