NCC BIO101 Homework 4 Chapter Latest 2021

BIO101 Intro to College Biology I

Homework 4 Chapter

Question 1In certain cancerous cells, the cell divides continuously even in the absence of a growth factor (signaling molecule) that indicates the cell should divide. Which of the following could NOT explain this?

a target protein that is always activated

a receptor molecule that is always activated

 a receptor molecule that is always turned off

a gene for cell division that is expressed when it should not be

a transduction pathway that is always turned on

Question 2Molecules such as glucose and amino acids are NOT lipid soluble and therefore they

combine with carrier proteins and pass across by facilitated transport.

require active transport to cross the cell membrane.

must be engulfed by a cell using endocytosis.

easily pass across the cell membrane.

must be converted to lipids before they can enter a cell.

Question 3Radioactive isotopes are used to tag proteins in the cell membranes of mouse cells. These cells are then fused with human cells in cultures. What is the likely outcome of the tagged mouse proteins?

The tagged proteins drift across cell membranes and are soon found dispersed across both human and mouse cell membranes.

The tagged proteins remain in mouse cells but move anywhere across the mouse cell membrane.

The tagged proteins remain in the mouse cells and keep their position on the membrane.

None of the answer choices will occur since mouse cell membranes are unlike human cell membranes.

None of the answer choices will occur since radioactive cells will soon die.

Question 4The pressure that is generated when water flows through a differentially permeable membrane is termed

crenation.

turgor pressure.

plasmolysis.

tonicity.

osmotic pressure.

Question 5What will happen to the water level in Figure 4.1?

It will remain the same on both sides.

It will decrease on both sides of the membrane.

It will rise in side A.

It will rise in side B.

It will rise on both sides of the membrane.

Question 6When an intestinal cell ingests substances inside very small vesicles that can only be seen with an electron microscope, this is

phagocytosis.

active transport.

pinocytosis.

exocytosis.

diffusion.

Question 7When you add sugar to your coffee or tea, the sugar is the

solvent.

solute.

gradient.

solution.

permeable.

Question 8Which cell junctions are commonly found in areas that are subject to stretching, such as the skin?

tight junctions

plasmodesmata

adhesion junctions

gap junctions

None of the answer choices is found between skin cells.

Question 9Which of the following is not true regarding active transport?

is associated with large numbers of mitochondria

moves molecules or ions against their concentration gradient

involves protein pumps

cannot be done by animal cells

is associated with nerve and muscle cells

Question 10Which type of membrane protein will be used to bind to hormones?

cell recognition proteins

enzymatic proteins

carrier proteins

receptor proteins

channel proteins