Notes The Cell Structures Functions What is Cell

Notes: The Cell Structures & Functions

What is “Cell Theory”? p The idea that all living things are made up of cells.

What’s so special about cells? p Cells are the smallest working units of all living things. Yeast Cells

Where do cells come from? p All cells come from preexisting cells through cell division. Bean Cells in Mitosis

Definition of the Cell p A cell is the smallest unit that is capable of performing life functions.

Would you like to see some examples? Even if you don’t, too bad.

Remember… p These are magnified images taken with microscopes p Some cells have been stained with color so you can see them better.

Nerve Cell

Bacteria Cell

Tree cells from the stomach of a possum.

Brain Cell

Cornstalk Cells

Mammalian Tissue • Smooth muscle are structurally the simplest muscle cells • Provide contractile forces for most internal organs • Controls flow of blood through vessels and moves food through digestive tract.

Two Types of Cells Prokaryotic p Eukaryotic p

Prokaryotic p One-celled organisms p Example: Bacteria p Few internal structures surrounded by membranes Cells Dividing: Bacteria from a Taxi Cab

Eukaryotic p p Contain organelles surrounded by membranes Most living organisms Plant Humans & Animals

“Typical” Animal Cell

“Typical” Plant Cell

Cell Parts and Functions Cell Wall Plant, not animal cells Outer layer, rigid, strong, stiff Made of cellulose

Cell Parts and Functions Cell Membrane Plant & animal cells Protects the cell Lets things in and out of the cell Location: around the cell

Cell Parts and Functions Nucleus p Plant & animal cells p Large & oval p Control center p Location: n n Inside the cell, Near the center

Cell Parts and Functions Nucleolus (Nucleoli) Plant & animal cells Makes ribosomes Location: inside the nucleus (dark spot) Nuclear Membrane Plant & animal cells Protects around nucleus Lets things in/out of nucleus (pores) Selectively permeable cell

Cell Parts and Functions Cytoplasm p Plant & Animal p Clear, thick, jellylike p Holds all organelles in cell p Location: in cell

Cell Parts and Functions Chromatin/Chromosomes p In Plant & Animal Cells p Contains genetic information/traits p Location: In nucleus

Cell Parts and Functions Endoplasmic Reticulum (E. R. ) p p p Plant & animal cells Network of tubes and membranes Transports materials and sends messages to all parts of the cell Two types: smooth and rough (has ribosomes) Location: attaches from cell membrane to nuclear membrane

Rough E. R.

Cell Parts and Functions Ribosome p Plant & Animal Cells p Makes proteins p Small circular shape p Location: n n In Cytoplasm or Attached to E. R.

Mitochondria p Plant & animal p Bean shaped with inner membrane p Makes energy/powerhouse p Breaks down sugar into energy p Location: In Cytoplasm

Mitochondria

Cell Structure & Function Vacuole Plant = few/large Animal = small Fluid filled sacs Stores food, water & waste Location: In cytoplasm

Vacuole

p What does a vacuole remind you of?

Golgi Bodies or Golgi Apparatus p Located in Plant & Animal Cells p Packages and secretes p Gets rid of waste p Location: in cytoplasm

p What does a Golgi Body remind you of?

GOLGI APPARATUS

Cell Parts and Functions Lysosome Plant & Animal Cells Contains digestive enzymes Destroys bacteria, old cell parts… Location: in cytoplasm Centrioles Plant & Animal Cells Helps the cell to divide Location: in cytoplasm

Cell Parts and Functions Cilia Most Plant, Animal & Bacteria Cells Short hair-like projections Used for movement Location: outside of cell Flagella Most Plant, Animal & Bacteria Cells Long whip-like tail Used for movement Location: outside of cell

What’s that?

Cell Structures and Functions Chloroplast Only in plant cells Contains chlorophyll Makes plants green Traps light energy from the sun Light Energy = Chemical Energy (Where photosynthesis occurs) Chemical Energy = Food for the Plant

Cell Structures and Functions Plastids p Found in Plant Cells p Stores extra food p Located in cytoplasm

Can you name these plant cell parts? A. B. C.

Cell Parts and Functions Cytoskeleton Also called Microfilament Plant & Animal Cells Made of thin hallow tubes Like a spider web Supports & transports “Super Highway” Microfilament (cytoskeleton) of mouse embryo fibroblasts, stained with FITC-phalloidin (100 fold magnification. )

Can you name these animal cell parts? Cell Membrane #1 #2 Rough E. R. #3 Ribosome's Cytoskeleton or Microfilaments #4 #5 Mitochondria