Answer:
a. The polarity of membrane phospholipids.
Explanation:
Phospholipids are the amphipathic lipids with polar heads and non-polar tails. The non-polar tails of two lipid layers form the core of the membrane while their heads are oriented towards both of the faces of the membrane. The polarity of the phospholipids does not affect the transport of substances. If a membrane has more of the saturated phospholipid tails in its core, the tight packing of the tails makes the membrane less permeable for large and polar substances.
On the other hand, a membrane with a greater proportion of unsaturated hydrocarbon tails in its core is more permeable. Cholesterol is also an amphipathic sterol and moderates the fluidity of membrane and thereby affects its permeability. A more fluid membrane is more permeable than a more solid membrane. Temperature affects the membrane polarity by affecting the membrane fluidity.
Answer:
Valves of the heart do the endocardium extenstions.
Explanation:
Endocardium is the inner most layer of heart containing tissue that lines the heart chamber and the outer most layer of the heart is called epicardium.
The main function of this structure is to protect the valves and heart chamber.
The endocardium consists of endothelial cells that controls myocardial function.
The homeometric and heterometric regulation is separated by myocardial system.
The endocardium also functions as a blood heart barrier thus controlling the ionic composition withih which the cadiomyocytes bathe.
There's sexual reproduction and asexual reproduction. Sexual reproduction involves both male and female in order to reproduce, while asexual reproduction involves an organism reproducing on its own without the help of another partner.
Coal is the natural source that was mind in the past century in Virginia.
