Answer: true
Explanation: In gel electrophoresis, the smaller the size/molecular weight of DNA the faster it moves across the gel and vise versa. This is as a result of the pore size of the gel which is usually prepared 1g of agarose in 100ml of distilled water. So a DNA fragment with 1000 base pairs will "struggle" its movement across the gel pore making it mive less faster and further. Movement and molecular weight of DNA are inversely proportional.
Answer:
The correct answer is 3: "<em>High levels of Ca2+ are expected to be found </em><em>within the sarcoplasmic reticulum</em>".
Explanation:
Muscular contraction is a highly regulated process that depends on free calcium concentration in the cytoplasm. Amounts of cytoplasmic calcium are regulated by <u>sarcoplasmic reticulum</u> that functions as a storage of the ion.
When a nerve impulse reaches the membrane of a muscle fiber, through acetylcholine release, the membrane depolarizes producing the entrance of calcium from <u>extracellular space</u>. The impulse is transmitted along the membrane to the sarcoplasmic reticulum, from where calcium is released. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. The calcium channel in the sarcoplasmic reticulum controls the ion release, that activates and regulates muscle contraction, by increasing its cytoplasmic levels. When <em>calcium binds to the troponin C</em>, <em>the troponin T alters the tropomyosin by moving it and then unblocks the binding sites,</em> making possible the formation of <em>cross-bridges between actin and myosin filaments.</em> When myosin binds to the uncovered actin-binding sites, ATP is transformed into ADP and inorganic phosphate.
Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
Variation: When one of that species develops another trait or skill that the others do not have.
Adaptation: When a species changes in order to survive a certain place or survive a predator
Yes they can. They have different vision than humans that’s extra strength.
