Chapter 2 Cell activity

Question 1

Functions of proteins

Answer 1

• * Structure: Keratin (hair, nails and skin strength), collagen (cartilage, deep layer skin strength and flexibility.
• * Transport: Cell movement, molecule movement.
• *Communication: (hormones, nerve cells)
• *Metabolism: enzymes are proteins; determines chemical reactions.
• *Movement: within cell/within molecule/whole cell →muscle cells)
• *DNA and enzymes: DNA controls the structure and function of every cell. Hence control of the individual.
STCMMD

Question 2

Organelles of the cell membrane

Answer 2

Mitochondria
Nucleus
Nucleolus
Rough ER
Smooth ER
Golgi apparatus
Cytoplasm
Cytoskelton
Membrane (F.M model)
Proteins( Receptor proteins, Channel proteins
, Carrier proteins)

Question 3

-Membrane/receptor proteins

Answer 3

-Membrane/protein receptors: Specific proteins in the cell membrane. They react to certain external molecules and the bind together. This triggers changes in the cell

Question 4

-Channel proteins

Answer 4

-Channel proteins: Proteins that pass molecules through the membrane, passive, facilitated transport, cant go against the concentration gradient

Question 5

-Carrier proteins

Answer 5

-Carrier proteins: Proteins that move, within the membrane to move molecules into/out of the cell, active and can go against the concentration gradient.

Question 6

Diffusion/Osmosis

Answer 6

Diffusion: Movement of molecules so that they are evenly spread amongst an area. Passive, movement across cell membrane. Cell membrane is differentially permeable; (allows some substances entry/exit others it doesn’t). Osmosis; water diffusion.

Question 7

Carrier mediated transport

Answer 7

Transport into/out of the cell via carrier or channel proteins. Bind to/pass through these proteins. Can become saturated, regulated by hormones. Passive/active,

Question 8

Vesicular transport

Answer 8

Movement of molecules via membranous bags (vesicles). Active.

Question 9

Forms of vesicular transport/ molecule type expelled

Answer 9

Endocytosis: Entry into cell, active
Exocytosis: Exit of of the cell, active
Pinocytosis: cell drinking(liquids)
Phagocytosis: cell eating(solids)