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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