Optional: Cell Structure

A cell whose cytoplasm has a concentration of 1M glucose is placed in a test tube containing .5M glucose. Assuming that glucose is not actively transported into the cell, which of the following best describes the tonicity of the external solution relative to the cytoplasm of the cell? A. hypotonic B. hypertonic C. isotonic D. turgid E. flaccid

A

The movement of a substance across a biological membrane against a concentration gradient with the help of energy input is? A. active transport B. diffusion C. osmosis D. exocytosis

A

How does Oxygen cross the plasma membrane of cells? A. active transport B. diffusion C. osmosis D. facilitated diffusion

B

Single celled organisms can move molecules in bulk across their membrane using which of the following? A. phagocytosis B. endocytosis, exocytosis, phagocytosis C. endocytosis D. exocytosis

B

What molecules in the membrane contribute to the permeability of a membrane? A. Nucleic Acids B. Proteins and Phospholipids C. Phospholipids D. Proteins

B

Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a salt solution become limp and soft. From this we can deduce that the cells of the celery stalks are? A. hypotonic to the fresh water but hypertonic to the salt solution B. isotonic with fresh water but hypotonic to the salt solution C. hypertonic to fresh water and hypotonic to the salt solution D. hypotonic to both fresh water and the salt solution E. hypertonic to both the fresh water and the salt solution

C

Plasmodesmata in plant cells are MOST similar to which of the following structures of animal cells? A. extracellular matrix B. desmosomes C. tight junctions D. gap junctions E. peroxisomes

D

_____________________ can freely diffuse across a lipid bilayer. A. sucrose B. carbon dioxide C. oxygen D. both b and c

D

Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through? A. gap junctions and plasmodesmata B. tight junctions C. desmosomes D. plasmodesmata E. gap junctions

E

Unlike simple diffusion, facilitated diffusion requires energy expenditure by the cell. True False

False

Water only diffuses across membranes until it reaches equilibrium. True False

False

Small molecules can move from the cytoplasm of one plant cell to a neighboring cell without crossing a membrane through plasmodesmata. True False

True

Choose all of the statements that are true of integrins a. integrins bind to proteins attached to the cytoskeleton b. integrins are involved in transmitting signals from the extracellular matrix to the cytosol c. integrins are amphipathic in nature d. integrins are transmembrane proteins

abcd

What types of organic molecules associated with cell membranes can be involved in cell-to-cell recognition? (Choose all that applies) a. integral membrane proteins b. phospholipids that are found in the membrane c. Carbohydrates attached to lipids or proteins in the membrane d. nucleic acids found in the lipid bilayer

ac

If a blood cell is placed into a solution of 10M salt (highly salty) what would you expect to occur? (Choose all that applies) a. the cell may begin to shrink as more water leaves it than enters it b. the cell will probably lyse (explode) as more water enters it than it can hold c. salt will enter the cell faster than water will leave the cell d. free water will leave the cell and enter the surrounding solution faster than it will enter the cell

ad

What molecules in the cell membrane can play a role in the movement of substances into and out of the cell? (Choose all that applies) a. carbohydrates b. transmembrane proteins c. phospholipids d. peripheral proteins

bc

Which of the following factors will negatively impact the rate of diffusion of a molecule? (Choose all that applies) a. A warm environment b. A media that is highly viscous c. A short distance between two concentrations of the molecule d. A low difference in the concentration of the molecule across the media

bd

What types of organic molecules associated with cell membranes can be involved in cell-to-cell recognition? (Choose all that applies) a. phospholipids that are found in the membrane b. nucleic acids found in the lipid bilayer c. Carbohydrates attached to lipids or proteins in the membrane d. integral membrane proteins

cd