Warm-up

1. Carbon atoms in organic molecules most commonly bond to atoms of hydrogen, oxygen, and:– calcium– magnesium– nitrogen – sodium

2. Which TWO of the following cell types do you think have more in common with each other:

• plant cells, • animal cells • bacterial cells

Why?

Cell Components

Objectives

• Identify the role of each cellular organelle

• List the major components of a plant and an animal cell

• Apply your knowledge of cellular components to a concrete analogy.

WHAT DO WE MEAN BY:

STRUCTURE and

FUNCTION ?

•STRUCTURE= how it is built/constructed

•FUNCTION= what it does (how it works)

Cells

• Smallest living unit • Range in size

– 1/12,000 of an inch

– Over a meter (nerve cell)

• Trillions of cells in the human body– Only 200

different kinds!

Organelles

• Small structures found inside the cell

• Have special jobs to help the cell survive

• Think of the organs of the human body!

Cell Membrane

• Boundary • Protection• Shape and structure• Selective

– Controls what substances enter and leave the cell

– Transports food, gases, and waste both in and out of cell

Cell Membrane Analogy“Security Guard”

Cytoplasm

• Material between plasma membrane and nucleus– Water, proteins,

salts, sugars

• Where the organelles “live”

Cytoplasm Analogy“FRUIT PUDDING”

Nucleus

• “Cell Brain”- control center of the cell • Stores DNA

– DNA strands are often stored as chromatin.

• Nucleolus – contains information to make ribosomes

• Nuclear Envelope - allows molecules to move in and out of cell

Nucleus Analogy“BRAIN”

Ribosomes

• Make proteins• Some float freely

in cytoplasm• Others attach to

the endoplasmic reticulum

Ribosome Analogy“KNITTING NEEDLES”

Endoplasmic Reticulum

• Maze of passageways

• Carry proteins and other materials from one part of the cell to another

Endoplasmic Reticulum

• Rough ER – transports proteins

• Smooth ER – contains enzymes to produce membrane lipids

Endoplasmic Reticulum Analogy“HIGHWAY”

Golgi Apparatus

• Sorts and packages the proteins and lipids made in the E.R.

• Sends them to different locations around the cell in secretory vesicles

Golgi Apparatus Analogy“POST OFFICE”

Mitochondria

• Provides energy for the cell

• Converts energy in food molecules into energy the cell can use to carry out its functions

Mitochondria Analogy “POWER HOUSE”

Cytoskeleton

• Network of protein filaments

• Helps cell maintain its shape

• Made up of:– Microtubules– Microfilaments

Cytoskeleton Analogy “STEEL BEAM SUPPORTS”

Lysosome

• Contain chemicals that break down food particles and worn-out cell parts– Break down old cell parts and

release them so they can be used again

• Autolysis

Lysosome Analogy“CLEANUP CREW”

Animal vs. Plant Cell

• DIFFERENCE:– Plant cell has a cell

wall, chloroplasts, and a vacuole

Cell Wall• Protection

– Very thick

• Prevents excessive uptake of water

• Strong walls hold the plant up against the force of gravity

Cell Wall Analogy“Wall”

Chloroplast

• Capture energy from sunlight and use it to produce food for the cell– Photosynthesis

• Have pigment chlorophyll which gives leaves their green color

Chloroplast Analogy“Grocery Store”

Vacuole

• Storage Sac:– Water– Organic

compounds– Waste– Pigments – Poisonous and

unpalatable compounds

Vacuole Analogy“POND”

Animal vs. Plant Cell

• DIFFERENCE– Animal cell has centrioles

Pop Quiz!

1. Which organelle provides energy for the cell?2. Which organelle is involved in protein transport?3. Which organelle is involved in packaging

proteins? 4. Which organelle is only found in an animal cell?5. Which organelle is only found in a plant cell?

Homework

• Finish Cell Graphic Organizer– Use Textbook to help!

Your Turn!• An analogy is a comparison of

one thing to another. A good analogy helps us understand the two things more clearly.

• Your job is to think of a good analogy that helps us understand the organelles in a cell and their functions, and then use that analogy to explain what a cell is and how it works.

Your Turn!Please include:

– Descriptive Title, Heading– Brief overview or introduction to your analogy.

Don't forget to say whether you are representing a plant cell or an animal cell.

– More detailed explanation of each part of the cell and how it fits into the analogy. Please include at least ten cell parts!

– A brief explanation of ways that your analogy does NOT perfectly describe the cell. (For example, the solar system analogy for the atom is not perfect, because the electrons do not move around the nucleus in predictable orbits like planets move around the sun.)

References• Prentice Hall’s Life Science: Science Explorer (2007).Pearson

Education, Inc.• Microsoft ClipArt• uhaweb.hartford.edu/BUGL/immune.htm • www.holisticeducator.com/neuron.htm • www.dkimages.com/.../The-Cell/The-Cell-68.html • www.biologycorner.com/bio3/notes-cell_membrane• micro.magnet.fsu.edu/mitochondria.html • www.canjo.net/k/ • srv2.lycoming.edu/ribosome/header.htm • utopiankitchen.wordpress.com• www.jeffsmusclestudio.com/muscleart.html • student.nu.ac.th/u46410320/vacuole.htm • www.eecs.berkeley.edu/strawberrydna.html • library.thinkquest.org/plcells/nuclues.htm