chapter 3

Are protein channels specified for the substance they transport?

yes

The tails of the phospholipids of the plasma membrane are composed of _____ and are _______? A) phosphate groups; hydrophobic B) fatty acid groups; hydrophilic C) phosphate groups; hydrophilic D) fatty acid groups; hydrophobic

D) fatty acid groups; hydrophobic

Active transport must function continuously because?

Diffusion is constantly moving solutes in opposite directions

What can get through the plasma membrane by simple diffusion?

Small uncharged molecules (Small nonpolar, hydrophobic) Gases

Plasma membrane are _____________ meaning they have both hydrophilic and hydrophobic parts.

Amphiphilic

Which of the following is not a component of the endomembrane system? A) mitochondrion B) Golgi apparatus C) endoplasmic reticulum D) lysosome

A) mitochondrion

Which plasma membrane component can be either found on its surface or embedded in the membrane structure? A) protein B) cholesterol C) carbohydrate D) phospholipid

A) protein

A typical prokaryotic cell __________________ compared to a eukaryotic cell. A.) is smaller in size by a factor of 100 B.) is similar in size C.) is smaller in size by a factor of one million D.) is larger in size by a factor of 10

A.) is smaller in size by a factor of 100

The ________ is the basic unit of life. A.) organism B.) cell C.) tissue D.) organ

B.) cell

The principal force driving movement in diffusion is__________ A. temperature B. particle size C. concentration gradient D. membrane surface are

C. concentration gradient

When viewing a specimen through a light microscope, scientists use _________ to distinguish the individual components of cells. A.) beam of electrons B.) radioactive isotopes C.) special stains D.) high temperatures

C.) special stains

Water moves via osmosis _________. a. throughout the cytoplasm b. from an area with a high concentration of other solutes to a lower one c. from an area with a high concentration of water to one of lower concentration d. from an area with a low concentration of water to one of higher concentration

c. from an area with a high concentration of water to one of lower concentration

Which of these do all prokaryotes and eukaryotes share? a .nuclear envelope b. cell walls c. organelles d. plasma membrane

d. plasma membrane

Facilitated diffusion utilizes _________.

proteins

Which of the following is found both in eukaryotic and prokaryotic cells nucleus. mitochondria. vacuole ribosome

ribosome

Membranes are ___________ permeable.

selectively