Answer:
B. hydrostatic and osmotic pressure
Explanation:
The mass movement of fluids into and out of capillary beds requires a transport mechanism far more efficient than mere diffusion. This movement often referred to as bulk flow, involves two pressure-driven mechanisms: Volumes of fluid move from an area of higher pressure in a capillary bed to an area of lower pressure in the tissues via filtration. In contrast, the movement of fluid from an area of higher pressure in the tissues into an area of lower pressure in the capillaries is reabsorption. Two types of pressure interact to drive each of these movements: HYDROSTATIC PRESSURE AND OSMOTIC PRESSURE.
The primary force driving fluid transport between the capillaries and tissues is HYDROSTATIC PRESSURE, which can be defined as the pressure of any fluid enclosed in a space. Blood hydrostatic pressure is the force exerted by the blood confined within blood vessels or heart chambers. Even more specifically, the pressure exerted by blood against the wall of a capillary is called capillary hydrostatic pressure (CHP) and is the same as capillary blood pressure. CHP is the force that drives fluid out of capillaries and into the tissues.
The net pressure that drives reabsorption—the movement of fluid from the interstitial fluid back into the capillaries—is called OSMOTIC PRESSURE (sometimes referred to as oncotic pressure). Whereas hydrostatic pressure forces fluid out of the capillary, osmotic pressure draws fluid back in. Osmotic pressure is determined by osmotic concentration gradients, that is, the difference in the solute-to-water concentrations in the blood and tissue fluid. A region higher in solute concentration (and lower in water concentration) draws water across a semipermeable membrane from a region higher in water concentration (and lower in solute concentration).
Explanation:
Pollination is the transfer of pollen grains from
an anther to a stigma . Pollen can be transferred
by an animal or by the wind. Fertilization takes
place inside the ovary when the nucleus
of pollen grains fuses with the nucleus of
an ovule to produce a zygote
Answer: This statement is true.
Answer:
C.
Adélie penguins are dependent on the existence of sea ice for access to their food supply.
Explanation: Their numbers are declining due to the loss of sea ice, so it's natural that this would be the answer.
Answer:
<em>The correct option is C) The small population size means that the new colony may have reduced genetic variation from the original population and that variation, in this case, included the dominant allele for Huntington's disease.</em>
Explanation:
The Afrikaner population of Dutch settlers in South Africa is descended mainly from a few colonists. Today, the Afrikaner population has an unusually high frequency of the gene that causes Huntington's disease, because those original Dutch colonists just happened to carry that gene with unusually high frequency. This effect is easy to recognize in genetic diseases, but of course, the frequencies of all sorts of genes are affected by founder events.