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.
Having the occasional alcoholic drink is unlikely to affect your fertility. But heavy drinking and smoking can reduce sperm quality, lower testosterone production, and make it harder to achieve an erection. It can also lead to liver damage, which affects both your general and reproductive health
Answer: Option "D".
Explanation: During exercise muscle cells release irisin protein is being released causing Beige adipocyte formation.
the secretion of Irisin leads to the improvement in muscle activity, bone mineral density, increasing the formation of brown like Beige adipocytes in the tissue.
Adipocytes are divided into two tissues namely white and brown. white tissues generally expand during excessive nutrition and brown adipocytes have mitochondria and burn the energy during exercises resulting into the break down of ATP molecules increasing the body heat.
Therefore, during exercise heat generated due to the formation of brown adipocyte tissue which are formed due to the release of irisin protein.
Answer: homo sapiens is the only species with a large enough oral cavity and a low enough larynx to allow for speech production.
<span>One line of evidence that speech only possible for modern homo sapiens is the anatomy of their throat. Speech depends on certain anatomical arrangements and the Homo sapiens is the only species with a large enough oral cavity and a low enough larynx that would allow speech.</span>
