and CORRECT Answers
A kinase is an enzyme that:
functions as a second messenger molecule
serves as a receptor for various signal molecules
adds a phosphate group to target proteins
regulates the production of second messenger molecules - CORRECT ANSWER - adds a
phosphate group to target proteins
Which of the following is not a characteristic that chloroplasts and mitochondria share?
The both have their own DNA.
They are both exhibit multiple membranes.
They are both part of the endomembrane system.
They are capable of reproducing themselves. - CORRECT ANSWER - They are both part
of the endomembrane system.
At the end of mitosis, each daughter cell has:
twice the DNA and half of the cytoplasm of the parent cell
identical amounts of DNA to that of the parent cell
half the DNA and half the cytoplasm of the parent cell
twice the cytoplasm and the same amount of DNA as the parent cell - CORRECT
ANSWER - identical amounts of DNA to that of the parent cell
Which molecule is not part of the cell membrane?
nucleic acid
lipid
protein
steroid
, phosphate group - CORRECT ANSWER - nucleic acid
Which statements most accurately describes diffusion?
ATP is used to pump ions across a membrane.
Ions move down their chemical gradient (from high to low concentration).
Ions move up their chemical gradient (from low to high concentration).
Transport proteins facilitate ion movement against their chemical gradient. - CORRECT
ANSWER - Ions move down their chemical gradient (from high to low concentration).
Active transport requires which of the following?
ATP
Ions flowing down their chemical gradient.
Ionophores
An electrical charge across the membrane. - CORRECT ANSWER - ATP
In a phospholipid, the phosphate head is hydrophobic while the fatty acid tails are hydrophilic.
T/F - CORRECT ANSWER - False
What is the basic macromolecule that all cell membranes are composed of?
proteins
phospholipids
nucleic acids
carbohydrates - CORRECT ANSWER - phospholipids
Amino acids of integral membrane proteins that cross the lipid bilayer would most likely be:
nonpolar and hydrophobic.
nonpolar and hydrophilic.
polar and hydrophobic.