Cell Membrane

A cell membrane controls what enters and exits a cell. This helps organisms maintain -

(a)  

Tags

NGSS.HS-LS1-3

What is the correct orientation of the phospholipids in the cell membrane (phospholipid bilayer)?

Label the hydrophobic and hydrophilic parts of the phospholipid bilayer.

a

b

Nonpolar and hydrophobic

Polar and hydrophilic

The cell membrane is called a ​ (a)   because it has many small parts that are pieced together. The "background" of the cell membrane is made of ​ (b)   and the "tiles" are usually ​ (c)   . Cholesterol is a type of ​ (d)   that is also found in the cell membrane. Sometimes ​ (e)   attach themselves to proteins or phospholipids in the cell membrane, as well.

• fluid mosaic
• phospholipids
• proteins
• lipid
• carbohydrates

What does selectively permeable mean?

Organize these options into the correct categories:

Groups:

(a) Able to diffuse simply

,

(b) Need help to diffuse

• Polysaccharides

• Na⁺

• Water (H₂0)

• Nucleotides

• Glucose (C₆H₁₂O₆)

• Polypeptides

• Large molecules

• Small molecules

• Cl^-

• Uncharged/nonpolar molecules

• O₂

• CO₂

• Charged or polar molecules

Tags

NGSS.HS-LS1-6

Channel proteins and gated proteins help large and polar/charged molecules pass through a membrane. Channel proteins are ​ (a)   while gated proteins are ​ (b)   .

• always open
• able to open and close
• always closed