Incomplete please thank and mark brainliest
While adding we need to follow that the units of mass i.e., kilogram and gram are converted into grams before addition and then follow the simple addition process. We can add two or more units of mass given in kilogram and grams like ordinary numbers. Always express grams as 3-digit numbers for example 3 g = 003 g.
Answer:
They speed up chemical reactions. Without them you wouldn't be alive. They break down macromolecules, and also lower the amount of energy needed for a chemical reaction to happen.
<h3><u>Answer;</u></h3>
The adrenal glands sit on top of the kidneys and release adrenaline, which affects heart rate.
<h3><u>Explanation;</u></h3>
- Adrenal glands are located at the top of each kidney. They produce hormones that help the body control blood sugar, burn protein and fat, react to stressors like a major illness or injury, and regulate blood pressure.
- The Adrenal glands are made up of two regions; the adrenal cortex and the adrenal medulla. <em><u>The adrenal medulla produces hormones adrenaline also epinephrine and noradrenaline also norepinephrine. </u></em>
- <em><u>Hormone adrenaline rapidly responds to stress by increasing your heart rate and rushing blood to the muscles and brain.</u></em>
Answer:
When a muscle cell contracts, the myosin heads each produce a single power stroke.
Explanation:
In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When the muscle fiber membrane depolarizes, the action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane and releases calcium into the sarcolemma. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin heads bind to the uncovered actin-binding sites forming cross-bridges, and while doing it ATP is transformed into ADP and inorganic phosphate which is liberated. Myofilaments slide impulsed by chemical energy collected in myosin heads, <u>producing a power stroke</u>. The power stroke initiates when the myosin cross-bridge binds to actin. As they slide, ADP molecules are released. A new ATP links to myosin heads and breaks the bindings to the actin filament. Then ATP splits into ADP and phosphate, and the energy produced is accumulated in the myosin heads, which starts a new binding cycle to actin. Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.