Chapter 8

A Tour of the Cell

How can we see cells?

Light microscope– Uses light and lenses to magnify

Electron microscope– Uses beam of electrons– Gives a 3-D picture

Not a flashcard.

Electron vs. Light

What can you see without a microscope?

Not a flashcard.

Here are some pictures of cellsView the size of cells

Not a flashcard.

Cell TypesCell Types

Bone Cell

Muscle Cell

Nerve Cell

Cartilage Cell

Blood Cell

Small IntestineCell

Not a flashcard.

Discovery of the Cell

Made possible by the development of the microscope

Robert Hooke first used a microscope in 1665

Examined a thin slice of cork Found similar formations, “a great many little

boxes,” when looking at stems of trees, carrots, and ferns

Cells – named after the small rooms in which monks lived

Cork cells Not a flashcard.

Cell Theory

The 3 Parts to the Cell Theory:

All living things are composed of one or more cells

Cells are the basic units of life

All cells come from pre-existing cells

There are 2 types of cells

ProkaryoticExample: bacteria

EukaryoticExamples: plant & animal

Which is Bigger?

Bacteria Cell Animal Cell Plant Cell

Small Bigger Biggest

Not a flashcard.

Cell Type: Prokaryotic

No true nucleus No organelles

with membranes

Cell Type: Eukaryotic

Has at least 1 true nucleus

Has organelles with membranes

Prokaryotes vs. Eukaryotes

Why aren’t cells large?

As cell size , the surface area to volume ratio

Rates of chemical exchange may then be inadequate for cell size

Cell size, therefore, remains small

Cell Size

Not a flashcard.

Surface Area to Volume RatioNot a flashcard.

Unicellular vs. Multicellular

UnicellularMade of only ONE cell

or MulticellularMade of more than one cell

Organelles

There are 16 organelles I would like you to know.

Be able to label each of them and describe their functions.

Not a flashcard.

Cell Wall

Not in animal cells

Provides: protection shape support

Cell Membrane

Made of phospholipids Selectively permeable Maintains homeostasis

The Cell Membrane…

Controls what enters and leaves the cell

Not a flashcard.

Cytoplasm

Clear fluid that surrounds the organelles

Jelly-like

The Cytoskeleton

Fibrous network in cytoplasm Provides support and maintains shape Made of microtubules

Nucleus

The cell’s control center

Contains DNA RNA is made here

Nucleolus

Inside the nucleus

Produces ribosomes

Mitochondria

Makes energy The more

mitochondria, the more energy the cell can produce! (muscle cells)

Endoplasmic Reticulum

A folded membrane attached to the nucleus

‘Intra-cellular highway’

Ribosomes

Small and ‘circular’ Assembles amino acids to make proteins

Vessicles

Small packages that transport proteins from the ER to the Golgi apparatus

Golgi Apparatus

Flattened sacs Packages proteins and lipids to leave the cell

Lysosomes

sacs of enzymes digests particles

Vacuoles

Stores food, enzymes, and waste

Plants: only 1 LARGE

Chloroplasts

Found only in plants Contains chlorophyll (green) Converts sunlight to useable energy

Elodea Cells Not a flashcard.

Centrioles

Used in cell replication; only in animal cells Pulls chromosomes apart

Cilia vs. Flagella

Locomotive appendages:

Cilia is short and hairlike (large #’s)

Flagella is longer and whiplike (small #’s)

Real Pictures of Cilia

Cilia

Not a flashcard.

It’s all connected! Not a flashcard.

Difference Between Plant & Animal Cells

Plant Cells Have: A Cell wall Chloroplasts Larger vacuole No centrioles

A Plant Cell Not a flashcard.

A Real Plant Cell Not a flashcard.

Another Plant Cell

Important Info!

Not a flashcard.

An Animal Cell Not a flashcard.

Another Animal Cell Not a flashcard.

Cell Cheer!

The End!

See you soon!