Cell Structure & Function

transcript

http://koning.ecsu.ctstateu.edu/cell/cell.html

Topic: Cell theory

• EQ: What are the parts of the cell theory?

What is a cell?

A cell is the smallest unit that is capable of performing life

functions.

Who first discovered cells?

• Robert Hooke discovered the first cells. He built the first microscope. He then viewed cork from an oak tree. This is what he saw.

He thought they looked like the little rooms,so he called them “cells”

What part did microscopes play?

• Microscopes allowed scientists to see cells and other things that were too small to be seen with just their eyes.

Time passed on….

• Better microscopes were built and other scientists began to look for cells in other places……….

• After many, many observations a theory was made…..called The Cell Theory

• The cell theory grew out of the work of many scientists and improvements in the microscope.

• Many scientists contributed to the cell theory.

Cell Theory

The three principles of the cell theory:

• 1. All living things are made up of cells. • 2. The cell is the smallest of all life• 3. All cells come from preexisting cells

through cell division.

ISN 52

• Create a Cell Theory Bubble map

Topic: Prokaryotic vs Eukaryotic Cells

• Prokaryotic

• Eukaryotic

2 Basic Types of Cells

• Prokaryotes (prokaryotic cells)– Cells that DO NOT have a nucleus– Examples: bacteria

• Eukaryotes (eukaryotic cells)– Cells that DO have a nucleus and other

organelles– Examples: plant cells and animal cells

Prokaryotic Cells

Prokaryotic

• DNA: free-floating, not surrounded by a membrane

• Organelles: Not many organelles

• Level of organization: One-celled (unicellular)

• Size: small

http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic

Plant Animal

http://library.thinkquest.org/C004535/eukaryotic_cells.html

Eukaryotic Cells• DNA: surrounded by a

membrane• Organelles: Many

specialized parts• Level of Organization:

Multicellular: plants, fungi, animals, and protists

Size: larger

Examples of Cells

Amoeba Proteus

Plant Stem

Red Blood Cell

Nerve Cell

Bacteria

Homework

Types of Cells

P la n t C e lls A n im a l C e lls

E u ka ryo tic C e lls P ro ka ryo tic C e lls

C e ll T yp e s

http://www-class.unl.edu/bios201a/spring97/group6

http://waynesword.palomar.edu/images/plant3.gif

“Typical” Plant Cell

“Typical” Animal Cell

http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif

Cell Parts

Organelles

Topic: Cell Organelles (Shape and movement

EQ: Explain the function of the 7 cell organelles.

Shape and movement

• Parts of a cell have unique functions. A cell is made up of different structures that keep it alive. They each have a different job.

What is an organelle?

• An organelle is a part of the cell that has a specific job. They are little organs or parts inside of a cell.

What is the Nucleus? • Directs cell activities (Boss of the cell)• Contains genetic material – DNA• Found in Plant and Animal Cells

What is the cell membrane?• Flexible covering

• Protects and controls movement in and out of the cell

• Found in plant & animal cells. It only allows certain materials to pass (selectively permeable)

http://library.thinkquest.org/12413/structures.html

What is a cell wall?

• Only in plants

• A stiff structure outside the cell membrane.

• Adds support & helps the plant keep its shape.

What is the cytoskeleton?

• A network of threadlike proteins that are joined together and help give the cell its shape and help it move.

Directions

•Cut out table on pg. 65 and glue in your ISN 56

Movement of materials in a cell

• EQ: Explain the function of the 7 cell organelles.

How do materials move in and out of the cell?

• Two processes:

• A. Diffusion• B. Osmosis

What is Cytoplasm?

• A fluid inside a cell that contains salts and other molecules.

• Surrounded by cell membrane

What is diffusion?

• The movement of molecules from an area of higher concentration to an area of lower concentration.

• Diffusion moves ALL KINDS of materials in/out of cells

What does diffusion look like?

• http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html

What is osmosis?

• The diffusion of water molecules through a membrane

• This process refers to transferring only WATER in/out of cells

What does osmosis look like?

• Osmosis

Why is osmosis and diffusion important?

Both of these processes allows for things the cell need (water, nutrients, etc.) to get in and wastes have a way to leave out.

Double-Bubble

What is diffusion? What is osmosis?

Where did you get this information?

diffusion osmosis

Topic: Cells Energy and Storage

• EQ: Explain the function of the 7 cell organelles

Eukaryotic Cell Organelles and Function

Mitochondria– Nickname: “The Powerhouse”– Function: Energy formation

• Breaks down food to make ATP– ATP: is the major fuel for all cell activities that

require energy

Animal Cell

Nucleus

Nucleolus

Rough Endoplasmic Reticulum

Smooth Endoplasmic Reticulum

Ribosomes

Golgi Bodies

Mitochondria

Cell Membrane

Cytoplasm

Vacuoles– Function: stores water– Only in plant cells

• This is what makes lettuce crisp– When there is no water, the plant wilts

Section 7-2

Figure 7-5 Plant and Animal Cells

Go to Section:

Plant Cell

Cell Membrane

Vacuole

Chloroplasts– Function: traps energy from the sun to

produce food for the plant cell– Green in color because of chlorophyll, which

is a green pigment– Found only in plant cells

Section 7-2

Figure 7-5 Plant and Animal Cells

Go to Section:

Plant Cell

Cell Membrane

Vacuole

Chloroplasts

Nuclear Membrane

• Surrounds nucleus• Made of two layers• Openings allow

material to enter and leave nucleus

Chromosomes

• In nucleus• Made of DNA• Contain instructions

for traits & characteristics

Nucleolus

• Inside nucleus• Contains RNA to build

proteins

Endoplasmic Reticulum• Moves materials around

in cell• Smooth type: lacks

ribosomes• Rough type (pictured):

ribosomes embedded in surface

Ribosomes

• Each cell contains thousands

• Make proteins• Found on ribosomes

& floating throughout the cell

Mitochondria

• Produces energy through chemical reactions – breaking down fats & carbohydrates

• Controls level of water and other materials in cell

• Recycles and decomposes proteins, fats, and carbohydrates

Golgi Bodies

• Protein 'packaging plant'

• Move materials within the cell

• Move materials out of the cell

Lysosome• Digestive 'plant' for

proteins, fats, and carbohydrates

• Transports undigested material to cell membrane for removal

• Cell breaks down if lysosome explodes

Vacuoles

• Membrane-bound sacs for storage, digestion, and waste removal

• Contains water solution

• Help plants maintain shape

Chloroplast

• Usually found in plant cells

• Contains green chlorophyll

• Where photosynthesis takes place

Cell Structure & Function

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