Unit 3 Exam

Which cellular organelle is represented by the diagram below?

• Protein

• plasma membrane

• ATP

• mitochondria

After a cookie has been digested, glucose

molecules enter the bloodstream by the process

of

• phagocytosis

• diffusion

• ingestion

• pinocytosis

A student conducted an original, well-designed experiment, carefully following proper scientific procedure. In order for the conclusions to become generally accepted, the experiment must

• contain multiple variables

• be repeated to verify the reliability of the data

• support the original hypothesis

• be conducted by a scientist

Red blood cells contain a higher concentration of

potassium than the surrounding blood plasma

does. This higher concentration is maintained by

the process of

• cyclosis

• osmosis

• simple diffusion

• active transport

Human red blood cells placed in a 2 % salt

solution appear to shrink, but those placed in a

0.4 % salt solution burst. Which statement best

supports these observations?

• Salt causes cells to swell

• Salt is actively transported across membranes

• The nucleus does not regulate water balance in the cell.

• Osmosis can occur in either direction across a cell membrane.

The arrows in the diagrams below represent the

direction of movement of a certain type of

molecule through the cell membrane of two

different cells. The dots represent the relative

concentrations of this molecule.

Which processes are illustrated by the diagrams?

• phagocytosis and diffusion

• phagocytosis and osmosis

• active transport and diffusion

• dehydration synthesis and circulation

Which organelle contains hereditary factors and

controls most cell activities?

• nucleus

• cell membrane

• vacuole

• endoplasmic reticulum

The ribosomes of plant cells are sites for the

synthesis of

• ATP

• sugars

• nucleic acids

• enzymes

Based on experimental results, a biologist in a laboratory reports a new discovery. If the experimental results are valid, biologists in other laboratories should be able to perform

• an experiment with a different variable and obtain the same results

• the same experiment and obtain different results

• the same experiment and obtain the same results

• an experiment under the different conditions and obtain the same results.

Which metabolic process is most closely

associated with the organelle represented in the

diagram below?

• intracellular digestion

• aerobic respiration

• synthesis of glycogen

• hydrolysis of lipids