Atomic and Bonding Chemistry
Biological Molecules
The Cell
Plasma Membrane Structure
Plasma Membrane Transport
100

What is the fundamental difference between covalent and ionic bonding?

Covalent involves shared electrons

Ionic involves transfer of electrons

100

An example of a monosaccharide is ________.

  • fructose
  • glucose
  • galactose
100

True or False? All cells have a cell wall.

False

100

Are membrane phospholipids fluid or stationary?

Fluid.

100

Most of the functions of a cell membrane, including transport and enzymatic function, are performed by

proteins

200

Magnesium has an atomic number of 12. How many protons, neutrons and electrons does it have?

12 protons

12 neutrons

12 electrons

200

What feature of fats makes them hydrophobic?

Fats have nonpolar hydrocarbon chains.

200

The function of chloroplasts is

photosynthesis

200

Phospholipids are important components of

the plasma membrane of cells

200

How does water moves via osmosis?

from an area with a low concentration of solutes to an area with a higher concentration of solutes.

300

The figure below shows five water molecules. What atoms are involved in hydrogen bonding?

oxygen and hydrogen atoms of different water molecules.

300

Amino acids can be distinguished from one another by

the chemical properties of their R groups

300

Why is the membranous compartmentalization of a cell important?

Because it allows different chemical conditions to be maintained in different parts of the cell.

300

How are phospholipids different from triglygerides?

Phospholipids have a hydrophilic phosphate head group and hydrophobic fatty acid side chains.

300

The principal force driving movement in diffusion is __________.

the concentration gradient

400

What is a compound?

A substance that contains two or more elements in a fixed ratio.

400

How are genes used by cells to build proteins?

The genes in DNA direct the synthesis of an RNA molecule, which is used to build a protein.

400

Cyanide inhibits mitochondrial function; as a result, the rate of

ATP synthesis decreases.

400

How do phospholipids assemble to form a membrane?

Phospholipid bilayer. Polar head groups face the extracellular and cytoplasmic side of the membrane, hydrophobic fatty acid side chains orient towards the inside of the bilayer.

400

Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient.

transport proteins; down

500

A single water molecule (H—O—H) is held together by

two polar covalent bonds.

500

A diet high in animal products and hydrogenated vegetable margarine may increase the risk for heart disease. This is because:

most animal fats are saturated and many hydrogenated vegetable margarines contain high levels of trans fats.

500

Name the organelles that are not components of the endomembrane system.

Ribosomes, mitochondria, chloroplasts, cytoskeleton

500

The fluid mosaic model describes the plasma membrane as consisting of

a phospholipid bilayer with embedded carbohydrates and proteins.

500

Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment:

is hypotonic to the protozoan.