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