Chapter 7 Review! Cellular Structure and Function

Directions Work in a group of 3-4 students We will go group by group to answer a question. If a group cannot answer a question correctly, the first group to raise their hand and is called on may answer the question. There is no penalty for guessing. Team with the most points at the end wins! I may deduct points for disruptive behavior …

Here we go … Good luck!

An electron microscope can magnify an object about how many times? 500,000

A light microscope can magnify an object how many times? 1,000

List the 3 principles of the cell theory 1.All living organisms are composed of cells 2.Cells are the basic unit of life 3.Cells come from pre-existing cells

Define: organelle Specialized structure which carries out a specialized function.

If a cell has a cell wall, is it a plant cell or an animal cell? How do you know? Plant cell b/c animal cells do not have cell walls.

What is the function of the lysosome? Digests & breaks down worn- down organelles and food particles.

Which organelle converts sugars into energy? (In an animal cell) The mitochondria

Where are proteins made? In the ribosomes

What is the function of the nucleus? Control center; holds DNA (genetic information)

Cells fall into two broad categories. What are they? Prokaryotes & Eukaryotes

The major structural difference between prokaryotes and the eukaryotes is … The nucleus … prokaryotes don’t have a nucleus & eukaryotes do have a nucleus.

Describe a eukaryotic cell. *contain a nucleus *has organelles *larger & more complex than prokaryotes

What are examples of eukaryotic cells? Plants and animals

Describe a prokaryotic cell. *no nucleus or membrane bound organelles *smaller, simpler than eukaryotic cells

What’s an example of a prokaryotic cell? Bacteria

Both eukaryotes and prokaryotes have a … Plasma membrane

What is the function of the plasma membrane? It regulates what enters and leaves the cell through selective permeability.

Why is the plasma membrane called a fluid mosaic model? It has a lot of different components and has fluidity

Describe the structure of the phospholipid bilayer. It has two layers of phospholipids arranged tail-to-tail

The heads of a phospholipid are (polar/non-polar) and the tails are (polar/non-polar) Heads: polar Tails: non-polar

Why are the non-polar tails pointing inward? Because they are hydrophobic and are being shielded from the watery interior and exterior

Besides phospholipids, list three other components of the plasma membrane. Transport proteins, cholesterol, carbohydrate chains.

What is the function of cholesterol in the plasma membrane? It helps maintain fluidity – keeps the tails from sticking together

What is the function of the carbohydrates attached to the proteins? Define a cell’s characteristics and helps the cell identify chemical signals

Identify A, B, C, D, & E in the diagram.

What do you think would happen to the plasma membrane if the cholesterol was removed? The membrane would become more rigid because the cholesterol helps with fluidity.

Define: homeostasis Maintaining an internal balance

What characteristic of the plasma membrane maintains a cell’s homeostasis? Selective permeability

True or false: Passive transport requires energy. FALSE!

List three examples of passive transport. 1.Diffusion 2.Facilitated diffusion 3.Osmosis

In diffusion, molecules move from an area of ____ concentration to an area of ____ concentration. High, low

How does facilitated diffusion differ from diffusion? Instead of molecules passing directly through the plasma membrane, molecules pass through transport proteins.

Active transport requires … ENERGY!

Na/K pump, endocytosis, and exocytosis are examples of … Active transport … molecules are moving against its concentration gradient & requires energy

This is a picture of what type of transport?

Our goal … Is for EVERYONE to earn an 80% (a B or better!) on exam!