Name: ___________________ Period: _________Unit 4 Cell Structure and Function

Two Basic Cell Types:Prokaryotic vs. Eukaryotic Cells

Remember….cells are the basic unit of life for ALL living things.There are two basic types of cells:Prokaryotic cells – found in ________________Eukaryotic cells – found in protists, _________, plants and ______________

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PROKARYOTES

EUKARYOTES

Same

What does size have to do with it?

• Prokaryotic cells are much smaller than eukaryotic cells. Why? – _____________ surface area to volume allows nutrients to easily and quickly reach inner parts of

the cell.– Eukaryotic cells are larger and cannot pass nutrients as quickly. They require specialized

organelles to:• carry out _______________• provides _____________• _________________ chemicals throughout the cell

DiscoveryWhy do we call them cells?

• In 1665, _____________________ was the first to view cells from ______ (dead plant material).• He called them “cells” because they looked like tiny ____________.

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Important Discoveries

Eukaryotic Cells

Cell Theory1. All living things are made of __________2. CELLS are the basic units of ____________ and ______________ in living things3. _________ CELLS are produced from ______________ CELLS

Cellular Transport NotesAbout Cell Membranes

1. All cells have a cell ___________________2. __________________

a. Controls what enters and exits the cell to maintain an internal balance called _______________________

b. Provides _________________ and support for the cell3. Structure of cell membrane

______________________-2 layers of phospholipidsa. Phosphate head is ___________________ (water loving)b. Fatty acid tails _________________ (water fearing)c. Proteins embedded in membrane

4. Cell membranes have pores (holes) in ita. __________________________________ Allows some molecules in and keeps other molecules

outb. The structure helps it be selective!

Types of Cellular Transport_____________________________

cell doesn’t use energy1. Diffusion2. Facilitated Diffusion

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Robert Hooke

Weeee!!!

low

high

Polar heads love water & dissolve.

Label the cell membrane to the right

3. Osmosis

________________________cell does use energy

1. Protein Pumps2. Endocytosis3. Exocytosis

Passive Transportcell uses no ________________molecules move ___________________Molecules spread out from an area of ____________ concentration to an area of ______________ concentration. (HighLow)Three types: 3 Types of Passive Transport

1. ________________2. ________________ __________________ – diffusion with the help of transport proteins 3. __________________ – diffusion of water

Passive Transport: 1. Diffusion

1. Diffusion: random movement of particles from an area of _________ concentration to an area of _____________ concentration.

(High to Low)Diffusion continues until all molecules are evenly spaced (___________ is reached)-Note: molecules will still move around but stay spread out.2. _________________ __________________: diffusion of specific particles through transport proteins found in the membrane

a. Transport Proteins are _______________ – they “select” only certain molecules to cross the membrane

b. Transports larger or charged molecules3.Osmosis: diffusion of _______________through a selectively permeable membraneWater moves from _____________ to _____________ concentrations

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This is gonna be hard work!!

low

high

Active Transportcell uses energy

actively moves molecules to where they are neededMovement from an area of low concentration to an area of high concentration

(Low High)Three Types:

• 1. Protein Pumps• 2. Endocytosis:• 3. Exocytosis

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How Organisms Deal with Osmotic Pressure

Bacteria and plants have ________ ________ that prevent them from over-expanding. In plants the pressure

exerted on the cell wall is called ____________ pressure.

A protist like paramecium has _____________ vacuoles that collect water flowing in and pump it out to prevent

them from over-expanding.

Salt water fish pump salt out of their specialized gills so they do not ____________________.

Animal cells are bathed in blood. Kidneys keep the blood _______________ by remove excess salt and water.

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