Biology 1013 Launchpad 3.2-3.4, 3.5, 3.6-3.7, & 3.8a

Why are chloroplasts essential to the survival of many animals as well as plants?

Animals do not have chloroplasts and must depend on organisms that can photosynthesize the energy they need.

How does the cell wall protect prokaryotic cells in a hypotonic solution?

Because cells swell in a hypotonic environment, the bacterial cell wall counteracts the outward osmotic pressure and prevents the cell from bursting.

Why are eukaryotic cells unaffected by streptomycin and similar antibiotics?

Eukaryotic protein synthesis is not disrupted because these antibiotics do not disrupt eukaryotic ribosomal activity.

How does the DNA of prokaryotic cells differ from the DNA of eukaryotic cells?

Prokaryotic DNA is contained in the cytoplasm, whereas eukaryotic DNA is contained in the nucleus.

How do penicillin and similar antibiotics affect prokaryotic cells?

These antibiotics disrupt the formation of the cell wall so it cannot counteract osmotic pressure in a hypotonic environment, resulting in cell lysis.

How do streptomycin and similar antibiotics affect prokaryotic cells?

These antibiotics interfere with protein synthesis.

How are eukaryotic cells different from prokaryotic cells? Select the TWO answers that are correct.

~Prokaryotic cells are generally smaller than eukaryotic cells. ~Eukaryotic cells have organelles, whereas prokaryotic cells do not.

Which statements describe the structure of the cell membrane? Select the TWO answers that are correct.

~The cell membrane is composed of a bilayer of phospholipids, each of which contains a hydrophilic head and a hydrophobic tail. ~The hydrophilic head interacts with the external environment or the cytoplasm, and the hydrophobic tail interacts with other phospholipid tails within the cell membrane.

Which tasks do water vacuoles and cell walls both perform in plant cells? Select the TWO answers that are correct.

~keep plant upright ~maintain cell shape

What functions do membrane proteins serve?

~transport wastes out of the cell that cannot otherwise cross the cell membrane ~transport nutrients into the cell that cannot otherwise cross the phospholipid bilayer