SSRFirst 10 minutes of class

Cell Race Review graphic organizer Notes Cell Test-Tuesday 10/2

Agenda9/25/12---Day 4

Smallest unit of all living things

Composed of organelles

Each organelle performs specific jobs so the cell can do it’s job

The Cell

Cell membrane Nucleus nucleolus Chromatin Nuclear envelope Microvilli Cytoplasm

Mitochondria Golgi body Endoplasmic

Reticulum Ribosome Centrioles

Organelles Know location of and function of the following sructures

Describe three organelles discussed yesterday

Three lines

Collins I

Discuss cell Continue notes Cell diagram and plasma membrane

diagram color and label

Agenda9/26---Day 5

The barrier surrounding each cell Separates the cells contents from the

surrounding environment Is selectively permeable This is the cells way of maintaining

boundaries

Plasma Membrane

Phospholipid bi-layer Meaning two layers Each layer consists

of a lipid tail connected to a phospo- head

The tails face each other, away from the external or internal environments

Structure of plasma membrane

Hydrophobic◦ The lipid tails are

water insoluble◦ They are “water

fearing”◦ They are non-polar

Hydrophilic◦ The protein heads of

each Phospholipid is water soluble

◦ They are “water loving”

◦ They are polar and interact well with other polar substances

Phospholipid bi-layer

1. Proteins◦ a. Peripheral proteins act as binding sites or

receptors◦ b. Integral proteins- proteins that span the

membrane act as transport protein◦ c. Glycoprotein- act as markers, which allow your

cells to be recognized as “self” cells 2. cholesterol

◦ Help to stabilize the plasma membrane

Throughout the membrane you will find

Channel Proteins◦ Passive movement

of material through pores

Carrier proteins◦ Molecule will bind to

the carrier protein causing it to open, allowing passage into the cell

Types of transport proteins

Use passive transport◦ Do NOT require energy◦ 1. diffusion- molecules move across membrane

through pores along a concentration gradient (high to low)

◦ 2. filtration-movement of water and other solutes from high to low concentration Based on a difference in water pressure between

external and internal environment Pushes out solutes Occurs in the kidneys

Channel proteins

Facilitated diffusion- ◦ concentration gradient still needed◦ Protein carrier is used because molecules are too

large to enter pores◦ Still passive transport, just needs help◦ No energy because it is using a gradient

Solute Pump (example Na/K exchange pump)◦ Moves molecules or ions too large to enter on own

AGAINST a concentration gradient ◦ REQUIRES ENERGY (active transport)

Carrier proteins

Several junctions are present in order for the cells to continue doing their jobs, while communicating with adjacent cells all the while staying anchored to each other!

Cells join to form tissue

Membrane junctions:◦ Tight junctions◦ Desmosomes◦ Gap junctions◦ Microvilli

Define the following terms and provide an example of where it occurs page 59