Biology

Which cell structure is correctly paired with its primary function? A. ribosome - protein synthesis B. mitochondrion - movement C. vacuole - cell division D. nucleus - storage of nutrients

A. ribosome - protein synthesis Ribosomes are the site of protein synthesis. Ribosomes are found both on the rough Endoplasmic reticulum and in the cytoplasm.

Cells need to bring in molecules to carry out cellular processes. Often, this requires moving the molecules across the cell membrane against the concentration gradient. How do these molecules get into the cell? A. passive transport by diffusion B. active transport using ATP C. passive transport by osmosis D. phagocytosis

B. active transport Active transport requires ATP and is used when solutes need to move against a concentration gradient.

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which of the following has occurred? A. The swollen gums have absorbed the saltwater solution. B. The saltwater solution lowers the temperature of the water in the gums. C. The salt in the solution has moved against the concentration gradient. D. The water in the gums has moved out due to the high concentration of salt in the solution.

D. The water in the gums has moved out due to the high concentration of salt in the solution The salt water solution is hypertonic to the cells of the gums. It contains a higher concentration of solute (salt) and a lower concentration of water. Water from inside the cells of the gums moves down the concentration gradient and out of the cells.

The cell membrane of the red blood cell will allow water, oxygen, and carbon dioxide to pass through. Because other substances are blocked from entering, this membrane is called A. perforated B. semi-permeable C. non-conductive D. permeable

B. semi-permeable A semi-permeable membrane allows some, but not all, molecules and ions to pass through.

There are some similarities between prokaryotic and eukaryotic cells. Which of the following structures is found in both prokaryotic and eukaryotic cells? A. lysosome B. mitochondrion C. nucleus D. ribosome

D. ribosome Prokaryotic cells do not have membrane-bound organelles. They do contain ribosomes, which are the site of protein synthesis.

Which characteristic do most plants have in common? A. they are unicellular B. they are prokaryotic C. they produce seeds D. they are autotrophic

D. they are autotrophic Almost all plants produce their own food using photosynthesis.

Which type(s) of cells have genetic material that is contained in a nucleus? A. bacteria B. only animal cells C. protists D. both plant and animal cells

D.both plant and animal cells Both plant and animal cells are eukaryotic. Eukaryotic cells have DNA (genetic material) contained in a membrane-bound nucleus.