<u>B. Secondary xylem</u> tissue makes up most of the wood of a tree.
<h3><u>What exactly is secondary xylem?</u></h3>
Secondary xylem is a sort of xylem produced by secondary growth. During initial growth, in contrast, the primary xylem develops. As a result, the secondary xylem is linked to the primary xylem by lateral growth as opposed to the vertical extension.
The kind of cambium that gives rise to each difference is another point of differentiation. The vascular cambium produces the secondary xylem, while the procambium produces the primary xylem.
Unlike trees and shrubs, non-woody plants lack secondary xylem. It gives such plants mechanical support by depositing lignin into their cell walls, thickening them. Compared to the major xylem, the secondary xylem is made up of tracheids and veins that are shorter and wider. In comparison to the primary xylem, it is also richer in xylem fibers.
Possible growth rings in the secondary xylem (or annual rings). Sapwood and heartwood are two differentiators of the secondary xylem in big woody plants.
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I believe it is D. More African elephants today naturally lack tusks compared to the elephant populations 100 years ago, because big game hunters sought elephants for ivory.
Remains the same: proton pumping rate, electron transport rate, rate of oxygen uptake
Decreases or goes to zero: Rate of ATP synthesis, size of the proton gradient
<span>(Gramicidin causes membranes to become very leaky to protons, so that a proton gradient cannot be maintained and ATP synthesis stops. However, the leakiness of the membrane has no effect on the ability of electron transport to pump protons. Thus, the rates of proton pumping, electron transport, and oxygen uptake remain unchanged.)</span>
All viruses rely on themselves
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The types of unconformities that can occur in rock layers are: ANGULAR, NONCONFORMITY and DISCONFORMITY.