Welcome Back! • Current Event? • 4.2 Bellringer • Film advertisements • Membranes (10:40) • Work on HW or finishing filming (time permitting) • HW: Draw a representation of a membrane, showing all parts. NOTE that we no longer have time to build one – so ignore the building instructions
21
Embed
Welcome Back! Current Event? 4.2 Bellringer Film advertisements Membranes (10:40) Work on HW or finishing filming (time permitting) HW: Draw a representation.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Welcome Back!• Current Event?• 4.2 Bellringer• Film advertisements• Membranes (10:40)• Work on HW or finishing filming (time
permitting)
• HW: Draw a representation of a membrane, showing all parts. NOTE that we no longer have time to build one – so ignore the building instructions
Membranes
PLASMA MEMBRANE- keeping it all together
• Isolates the cell from external world• Regulates entry and exit to the cell
• Made up of phospholipids
• The 2 layers of phospholipid molecules are called the phospholipid bilayer
Phosphate
Fatty acid tails
1 phospholipid
Plasma membrane• Called a fluid mosaic because of the different
parts AND b/c phospholipids move around.
Phospholipid “Sandwich”• phosphates touch
watery sides (“the bread”)
• The fatty acids (lipids) “hide” creating the inside of the PM.
phosphate
fatty acids
You are Watery
• The fluid that surrounds all cells in body (interstitial fluid) AND the cytoplasm is:• mostly water• with• salts, proteins, lipids, carbohydrates,
sugars, amino acids, nucleotides, dissolved into it
• Ex: Think liquid in a blister or tears or sweat
Cytoplasm
• Made of:• Function:
–Location of most of the cells metabolic activities (aka: the biochemical reactions that support life)
–Gives cell “fullness”
Define: Mosaic• Mosaic is the art of creating images with an
assemblage of small pieces of colored glass, stone, or other materials
• For example Snowflake Mosaic!
•Other parts of the “mosaic” are…–Proteins do a whole host of things–Cholesterol acts as a stabilizer
Protein Functions
1. Transport
• Move molecules in or out of the cell that can’t cross the membrane
2. Signal Reception
• E.g. receives signals from hormones
• Cell can change activity or gene expression
3. Identifier
• E.g. type A or B blood
• Body can know what cell it is and not to attack it
Blood Transfusions Gone Wrong
4. Cell Connections
• Connect cell to cytoskeleton (interior side)
• Connect cell to other cells (exterior side)
Your Task
• Build a model of the cell membrane out of materials of your choosing
• Think of things you have lying around or waste products (e.g. toilet paper tubes)
• Must include:– Phospholipid bilayer– 4 types of membrane proteins– Labels
• 3D preferred
New Task
• Draw a representation of the membrane
• Include all parts you were supposed to construct and label