Unit 2: Extracellular components

Question 1

What do integrins do?

Answer 1

transmit signals from the extracellular matrix to the cytoskeleton

Question 2

Which structure forms cytoplasmic channels that connect adjacent plant cells through the cell walls?

Answer 2

plasmodesmata

Question 3

Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through

Answer 3

gap junctions

Question 4

a primary function of the middle lamella associated with plant cells

Answer 4

It glues adjacent cells together.

Question 5

The cell walls of bacteria, fungi, and plant cells, and the extracellular matrix of animal cells are all external to the plasma membrane. Which characteristic is common to all of these extracellular structures?

A) They must block water and small molecules to regulate the exchange of matter and energy with their environment.
B) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume.
C) They are constructed of materials that are synthesized in the cytoplasm and then transported out of the cell for assembly.
D) They are composed of a mixture of lipids and nucleotides.

Answer 5

C) They are constructed of materials that are synthesized in the cytoplasm and then transported out of the cell for assembly

Question 6

A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in the _________

Answer 6

extracellular matrix

Question 7

Passive leakage of partially digested material from the small intestine into the human abdominal cavity may result from defects in which type of intercellular junction?

Answer 7

tight junctions

Question 8

When H. V. Wilson exposed two species of differently pigmented sponges to a chemical that disrupted intercellular junctions, the cells of the sponges dissociated. Wilson then removed the chemical that caused dissociation and mixed the cells of the two species. He found that the sponges reassembled and that the cells from one species did not interact or form associations with the cells of the other species

Why?

Answer 8

The molecules responsible for cell-cell adhesion (cell junctions) differed between the two species of sponge

Question 9

Cyanide binds to at least one molecule involved in producing ATP. In a cell exposed to cyanide, most of the cyanide will be in ________.

Answer 9

mitochondria

Question 10

Which cell would be best for studying lysosomes?
A) muscle cell
B) nerve cell
C) bacterial cell
D) phagocytic white blood cell

Answer 10

D) phagocytic white blood cell

Question 11

Which structure is part of the endomembrane system?
A) mitochondrion
B) Golgi apparatus
C) chloroplast
D) centrosome

Answer 11

B) Golgi apparatus