Cell Structure and Function

Cell size comparison

Bacterial cell

Animal cell

What jobs do cells have to do for an

organism to live…

Gas exchange

CO2 & O2

Eat (take in & digest food)

Make energy

ATP

Build macromolecules

proteins, carbohydrates, lipids, nucleic acids

Remove wastes

Control internal conditions

Respond to external environment

Build more cells

growth, repair, reproduction & development

(homeostasis)

Cell Membrane

Structure Lipid bilayer embedded

with proteins

Function controls what enters or

leaves cell

O2,CO2, food, H2O, nutrients, waste

recognizes signals from other cells

allows communication between cells

All Cells!

Cytoplasm

Structure

Fluid in the cell

Contains water,

nutrients, and proteins

Function

Supports the cell

structures

All Cells!

Cytoskeleton

Structure

Thin tubes and filaments

made of proteins

Function

Helps the cell: move,

Keeps its shape

Organizes its parts

Think skeleton

Not in Prokaryotes

All Eukaryotes

Vacuoles

Structure

Large membrane sac

Function

Store food, water, waste, and nutrients

Plants have a large, central vacuole that fills with water and pushes against the cell wall causing the plant to stand upright

Not in Prokaryotes

Only in Plants and Protists

Vesicles

Structure

Small membrane

sac

Function

move material

around the cell

Like proteins,

food, waste

products, etc.

Not in Prokaryotes

All Eukaryotes

Lysosomes

Structure

Small membrane sac filled with digestive

enzymes

Function

Digest food

Clean up waste

Recycle old parts

Not in Prokaryotes

Animals and Some Protists

Mitochondria

Structure

Outer membrane surrounding an folded inner membrane embedded with many proteins

Function

Makes ATP using the energy from glucose

Cellular Respiration

Glucose + O2 ATP + CO2 +H20

Not in Prokaryotes

All Eukaryotes

Singular = Mitochondrion ATP

Chloroplast Not in Prokaryotes

Only in Plants and Some Protists

Structure

Double membrane surrounding thylakoids which contain the pigment chlorophyll (green)

Function

Photosynthesis to make glucose

Sun light + CO2 +H20 Glucose + O2

Cell Wall All Prokaryotes

Fungi, Plants, and some Protists

(Not Animals)

Structure

Rigid Layer that lies outside the

cell membrane

Bacteria – peptidoglycan (proteins and sugars)

Plants – cellulose

Fungi – chitin

Function

Structure and support

Nucleus

Structure

Nuclear membrane with nuclear pores

Contains the nucleolus

where ribosomes are made

Filled with DNA

Function

Stores and protects the DNA

Not in Prokaryotes

All Eukaryotes

Ribosomes

Structure

Small structures made of proteins

and RNA

some float in cytoplasm

some attach to ER

Function

Make proteins using instructions

from the DNA

All Cells!

Rough Endoplasmic Reticulum

Not in Prokaryotes

All Eukaryotes Structure

A system of interconnected

membrane folds/sacs

embedded with ribosomes

Usually found connected to

the nucleus

Function

Package the proteins made by

ribosomes into vesicles to be

transported around the cell

Smooth Endoplasmic Reticulum

Structure

A system of interconnected

membrane tubes (with no

ribosomes)

Usually found with the

Rough ER

Function

Builds lipids

Breaks down toxins

Makes vesicles

Not in Prokaryotes

All Eukaryotes

Golgi Apparatus

Structure

Membrane folds/sacs

Function

Modifies, sorts, labels,

packages, and ships

proteins and lipids

UPS store

Not in Prokaryotes

All Eukaryotes

DNA

RNA

ribosomes

endoplasmic

reticulum

vesicle

Golgi

apparatus

vesicle

protein on its way!

protein finished protein

Making Proteins

TO:

TO:

TO:

TO:

nucleus

*Centrioles*

Structure

Two short cylinders

made of proteins

Function

Organize the parts

of the cytoskeleton

that help with cell

division

Not in Prokaryotes

Only Animals and some Protists

Cilia

Structure

Short, hair-like structures

made of proteins covered in

membrane that extend from

the surface of the cell

Function

Help a cell move through a

watery environment

Or, help move air and fluids

over the cell’s surface

Not in Prokaryotes

Only Animals and Some Protists

Protist Video

Flagella

Structure

Long, hair-like structures

made of proteins covered in

membrane that extend from

the surface of the cell

Function

Moves the cell through its

environment

Singular = Flagellum

Some Prokaryotes

Some Animals and Some Protists

Plasmid

Structure

A small, extra ring of DNA

Function

Provides extra genetic

information

Can be swapped with other

bacteria

May carry antibiotic resistance

genes

Only Prokaryotes

Capsule

Structure

Outer covering of sticky

carbohydrates that bind to

the cell wall

Function

Protects the cell from drying

out and harsh chemicals

Keeps bacteria from being

broken down

Helps bacteria stick to other

cells

Some Prokaryotes

Pili

Structure

Short, thick, hair-like

structures made of

protein found on the

surface of bacterial cells

Function

Help bacteria stick to

other cells and surfaces

Allow bacteria to share

plasmids

Some Prokaryotes