correct AnswerAnswer:
D- D and A
Explanation:
REAL EXPLANATION
<h3><em>Chloroplasts take energy from the sun ad make it into food by a process called photosynthesis.... it then makes the energy to power the plant..... </em></h3><h3><em>Mitochondrions are called the power house of the cell, powering and letting the cell do its work transporting more energy into the plant....</em></h3>
This means that a single carbon atom can form up to tetravalent bonds with other atoms
Answer and 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, tropomyosin is obstructing binding sites for myosin on the thin filament. 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 released. Myofilaments slide impulsed by chemical energy collected in myosin heads, producing a power stroke. 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:
NO. Mitosis involves one set of nuclear division and results in two nuclei that are exactly the same as the original. On the other hand, meiosis involves two sets of nuclear divisions.
Explanation:
Mitosis is a type of cell division normally occurring at the sites of growth and development of new tissues and also at sites of repair. It also occurs during asexual reproduction of organisms. Each mitotic cell division is a process that follows distinct phases.
Each mitotic division results in the formation of two daughter cells which are genetically identical to the parent cell, that is they have the same number and type of chromosomes as the parent cell.
During telophase, a nucleolus develops in the nucleus of each daughter cell. The cytoplasm divides in the process called cytokinesis. An invagination develops and finally splits the cell into two daughter cell each with its own nucleus and cytoplasm.
