Which traits are characteristic of single-celled organisms?

choose all answers that are correct.

a.
have different cells for different tasks

b.
often derive nutrition directly through their cell membranes

c.
require few resources

d.
all have a nucleus

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Which of the following are not included as modern mammals that evolved during the eocene epoch? primates artiodactyls perissodactyls none of the above

Which survival need shortage would most affect articular cartilage's ability to rebound after joint compression, and why does it have this effect? which survival need shortage would most affect articular cartilage's ability to rebound after joint compression, and why does it have this effect? nutrients, since the majority of cartilage is made out of polysaccharide glycosaminoglycans (gags). water, since it makes up to 80% of cartilage's content and cushion articular bone surfaces. normal body temperature, since higher temperatures would slow down necessary biochemical reactions. oxygen, since cartilage cells receive this gas directly from nearby blood vessels?