The Cell Membrane

A. Phospholipid

1. They have a polar head that is hydrophilic (water-loving).

2. They are made of nonpolar tails that are hydrophobic (water-fearing).

B. Phospholipid Bilayer

1. The plasma membrane is made of 2 layers of phospholipids with polar heads pointing out and nonpolar tails pointing in.

What the phospholipid bilayer look like?

C. 3 Proteins in the Membrane

1. Transport protein: act like doors or channels that allow molecules to pass through the membrane. (Cell phone)

2. Receptor proteins: transfer information to the inside of the cell. (Texting)

3. Recognition proteins or glyco-proteins. These are name tags. (caller ID)

Movement Through the Cell Membrane

D. Selectively Permeable D. Selectively Permeable MembraneMembrane

Only certain molecules are allowed to pass freely.

So how do materials move in and out of a cell?

1. Passive transport – NO energyA. Simple Diffusion (Osmosis)B. Carrier-facilitated Diffusion

2. Active transport – needs energy

Diffusion of Kool Aide in water

A. Simple Diffusion• No energy is needed.

Molecules move from an area of high concentration (where there are many molecules) to an area of low concentration (where there are less molecules).

• Molecules spread out evenly and reach an equilibrium.

B. Osmosis1. Osmosis is the Diffusion of WATER.

Water molecules move from an area of high concentration (where there are many water) to an area of low concentration (where there are less water).

2. NO energy needed!

1. Water moves by diffusion.2. Membrane is selectively permeable.

Dictionary says: “Facilitate: to make easier; to help something happen”

So who facilitates in the cell membrane?

C. Facilitated DiffusionC. Facilitated Diffusion• The TRANSPORT PROTEINS move molecules,

they are facilitators or helpers.

• No energy needed because molecules are moving from a higher concentration (lots of molecules) to a lower concentration (few molecules).

Active TransportActive Transport• Transport Proteins move or pump molecules

by using energy.

Why is energy needed?

• Molecules move from a low concentration (few) to a higher concentration (many).

What do you know?

Use your notes to help!!

Name differences between simple diffusion & facilitated diffusion.

What is the smallest

living thing?

Power Point #2

The Cell

Name a structure found in

eukaryotes but not in prokaryotes.

Nucleus,Organelles

Bacteria is what type of cell?

Prokaryotic Cell

Are prokaryotes simple cells or complex cells?

Simple Cells

Are prokaryotes unicellular or multicellular?

Unicellular

Are plants and animal cells

eukaryotic cells or prokaryotic cells?

Eukaryotic Cells

Are eukaryotic cells simple cells or complex cells?

Complex Cells

Are eukaryotic cells unicellular or multicellular?

They can be both unicellular or multicellular

Is a virus living or nonliving?

Nonliving

What is the function of the

cell membrane?

Acts as a boundary between the cell and

its environment. Controls what enters and leaves the cell

What is the cytoplasm?

A jelly-like substance in the

cell that holds the organelles in place

What is the function of the

lysosomes?

To break down worn out

organelles and debris

What is the function of the

nucleus?

It contains the DNA.

Control center for the cell

What is the function of the

smooth ER?

To synthesize lipids

Which organelle packages proteins

into vesicles?

The Golgi Complex

Which type of cell transport (active or passive) requires

no energy?

Passive Transport

How do cells move material from an

area of high concentration to an

area of lower concentration?

Active Transport

Which part of the phospholipid is water loving?

The polar head is hydrophilic

What is the function of the

receptor protein?

Transfers information to the inside of the cell

What is a recognition

Protein?

These are the name tags

What are the Transfer Proteins?

Doors or channels that allow

molecules to pass through the membrane

Energy is stored in fats or proteins. Which organelle

produces ATP from these energy

sources?

Mitochondria