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.
Answer:
Its location.
Explanation:
The main difference between pyrogenesis and setting garbage on fire in a landfill is that pyrogenesis process occurs on the surface whereas garbage on fire in a landfill occurs inside the soil at certain depth. Pyrogenesis is an extreme thermal process that converts organic matter into gas made up of hydrogen and oxygen whereas garbage on fire in a landfill decomposes garbage that breaks down materials in simpler substances.
Answer:
H. It represents the actual size but it is big enough for the eye to see making it extrememly accurate
Explanation:
It wakes up the hormones in your body so you can reproduce in the first place, and it also helps to mature and prepare your body, and your cells, so it is able to reproduce. By waking up those hormones, your body is able to perform reproductive processes
Answer:
Option A , Sex
Explanation:
In anthropology, sex and gender are two distinct words and have entirely different meaning. Sex is something related to biology and gender is something defined by society based on the sexual differences. Sex defines the biological differences between the male and female. Gender represents the cultural constructions meant and to be followed for any person carrying any particular sexuality
Hence, the correct answer is option A
