Answer:d.are eventually replaced by electrons from photosytem 11
Explanation:there are two photosystems in the photosynthetic process.PSI and PS II. PS I has a reaction center called P700 because it's chlorophyll has a maximum absorption of 700nm wavelength.PSII has a reaction center called P680nm for similar reason.when an excited electron is transferred to P700,it becomes excited.this electron is passed down from from acceptor to another, until it is used to reduce NADP+ to NADPH.this electron is replaced when P680 gets excited by a photo of light and splits water to release electrons , protons and Oxygen
Plants release oxygen into the atmosphere during photosynthesis while respiration by plants and animals and the decomposition and decay of dead organisms releases carbon dioxide into the atmosphere. These three produce maintain a cycle in which plants and animals depend on and benefit from each other.
Answer: Coastline
Explanation:
The erosion is caused by waves from by the storms
Blood type doesn't fall into the category of dominant/recessive genes exactly; rather it combines this with the properties of incomplete dominance. Ignoring the Rh factor, there are 3 alleles for blood type, I^a,I^b, and i. You will be type A if you have I^a I^a or I^a i and type B if you have I^b I^b or I^b i. You can also get type AB by having the combination I^a I^b or be type O if you have i i. If you need to use dominant/recessive, you can say the A and B allele are dominant over the O allele and codominant with one another.
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.