IB Biology 1.3 and 1.4 Cell Membrane

Which process(es) occur by osmosis?

• Uptake of water by cells in the intestine

• Gain of water from a plant cell in a hypertonic environment

• Evaporation of water from sweat on the skin surface

• Movement of water in the blood stream

Tags

NGSS.HS-LS1-3

What is the essential feature of the Davson-Danielli model of the membrane structure?

• A phospholipid monolayer with intrinsic and extrinsic proteins

• A layer of protein sandwiched between two layers of lipid

• A phospholipid bilayer with intrinsic and extrinsic proteins

• A layer of lipid sandwiched between two layers of protein

Which molecule regulates the fluidity of the cell membrane?

• Phospholipids

• Cholesterol

• Glycoprotein

• Peripheral protein

Which type of transport happens in the sodium-potassium pump?

• Facilitated diffusion

• Osmosis

• Active transport

• Simple diffusion

Which molecule is an integral protein?

• A

• C

• E

• F

Which molecule is a peripheral protein?

• A

• C

• E

• F

Which part of the cell membrane is pictured here?

• Glycoprotein

• Cholesterol

• Glycolipid

• Phospholipid

The salt concentration inside a Paramecium is 1.8%. The salt concentration in the surrounding medium suddenly drops to 0.2%. What will be the likely response?

• The cell will lose salt to the medium.

• The contractile vacuole will expel more water.

• The cell will swell and eventually burst.

• The membrane will become more permeable to salt.

Tags

NGSS.HS-LS1-3

Which evidence falsifies the Davson-Danielli model?

I. The presence of globular proteins within the phospholipid bilayer

II. Non-polar amino acids cause proteins to remain embedded in membranes.

III. Membrane Proteins remain in a fixed position inside a membrane.

• I only

• I and II only

• II and III only

• I, II and III

What is osmosis?

• The movement of water through a membrane from a low to a high solute concentration.

• The movement of solutes through a membrane from a high to a low water concentration.

• The movement of water through a membrane from a high to a low solute concentration.

• The movement of solutes through a membrane from a low to a high water concentration.