Cell theory…

• Cells come from other cells

• All things are made of cells

• Named by Robert Hooke when he observed cells in cork oak

• Monk’s cells in monastery

Hooke’s microscope – late 17th century

Light source

Eye piece

LT#1 Structure & Fxn of Plasma (cell) Membrane

• The plasma membrane separates the inside of the cell from the outside

• It is made up of phospholipids• Phospholipids are fats with a

phosphate group attached• Fats alone are hydrophobic• The phosphate groups are

hydrophilic

Glycocalyx – glycoprotein / glycolipid / glycocarb = area adjoining the cell that provides specific bio markers that allow cells to recognize each other

LT#1 The molecules involved with the Fluid Fluid Mosaic ModelMosaic Model of the plasma membrane.

• The fluid mosaic model is a double bilayer of lipids imbedded with dispersed proteins

• The bilayer consists of:

• Phospholipids: polar heads, nonpolar tails

• Cholesterol: steroid• Glycolipids: lipids

bound with carbohydrate

LT#2 & #3 Structure & Fxn of Nucleus; Role of DNA

• The nucleus consists of the nuclear envelope, nucleoli, chromatin, and proteins

• It contains the genetic library w/blueprints for proteins (DNA)

• It dictates the kinds and amounts of proteins to be made

• We have 46 chromosomes: 23 from mom and 23 from dad

LT#2 & #4 The role of ribosomes & 3 RNAs. • Fxn of nucleolus = site of ribosome

prodxn• Transcription = synthesis of RNA under

the direction of DNA• mRNA carries information from DNA to

ribosomes• Ribosomes are made from proteins and

rRNA, which come together to form • tRNA (a molecular machine ) that can

read and translate the information they carry into proteins.

LTs #4-#8

• See Chart

LT#9 Describe transport across the plasma membrane. Passive transport; diffusion; random nature of diffusion; concentration gradient

• Passive transport requires no E (ATP)• E.g. Diffusion of nonpolar & lipid

soluble substances– Diffuse directly through the lipid bilayer– Diffuse through channel proteins

• Random because it can go either way• Concentration gradient – a difference

in concentration between 2 points (cell membrane)

LT#9 What is osmosis? Be sure you can differentiate between a hypertonic, hypotonic and isotonic situation! Essay!

• Osmosis is the diffusion o f water across a semipermeable membrane

• Hypertonic – solutions with [solute] > cytosol

• Hypotonic – solutions with [solute] < cytosol

• Isotonic – solutions with same [solute] as cytosol

LT#9 If you add distilled water to blood, what will happen to red blood cells relative to the 3 states?

• If you add distilled water to blood the RBC would burst because RBC contain 0.7% salt so distilled water is a hypertonic solution (to the cell) and water diffuses into the cell POP! (lyse)

LT#9 What is the difference between active and passive transport?

• Active transport requires ATP• Passive transport does not require

E (ATP)