Cell Structure and Function What the cell is going on here?

Cell Structure and Function

What the cell is going on here?

CELL BIOLOGY

All living things are made up of small individual units called cells. Cells are the smallest functioning living unit. Cells can not normally be seen with the naked eye. To usually observe a cell, you need a microscope!

Robert Hooke and Anton van Leeuwenhoek used the first 'primitive' microscopes to observe stuff in the mid 1600's! In the 400+ years since, improvements in the microscope have allowed scientists to observe cells better and to develop the cell theory.

The Cell Theory1. All organisms are made up of one or

more cells (unicellular or multicellular).

2. All cells carry out the 7 life functions.

3. All cells come from preexisting cells. BUT...

Exceptions to Cell Theory

A. Where did the first cells come from? CHICKEN AND THE EGG SYNDROME

B. Viruses are NOT composed of cells. But they do contain genetic material (DNA and/or RNA). They also can reproduce in the presence of a host cell.

C. Some cell parts (mitochondria and chloroplast) contain their own genetic material (DNA and/or RNA) and can reproduce in a cell.

Remember:

3 PARTS TO THE CELL THEORY

&3 EXCEPTIONS TO THE CELL

THEORY

a great way to see how big different things are; good metric review

http://www.cellsalive.com/howbig.htm

How Life is Organized...

Atoms and Molecules

the building blocks of everything in the universe

Organelles small parts of cells that have

specific functions different organelles have

different jobs

Cells the building blocks of life all living things are made up of one

(unicellular) or more (multicellular) cells

there are many typesex. muscle cells, neurons (brain cells),

skin cells, bone cells, blood cells

Tissue a group of cells that perform a

certain function ex. muscles, tendons, nerves

Organs a group of tissues that

perform a certain function

like organelles, different organs carry out different functions ex. brain, heart, skin, liver, intestines

Organ Systems

a group of organs that perform a certain function

organ systems have specific jobs ex. digestive system,

circulatory system, nervous system, reproductive system

Organism

a thing that carries out the 7 life functions

Population

a group of organisms of the same species in a given area

Community

a group of populations in a given area

Ecosystem

a community and the physical non-living environment that it exists in

Biosphere

the region of earth where life exists

all ecosystems on the planet make up the biosphere

As microscopes improved over the years, scientists were able to see into cells with more detail. There were able to see that there are two main types of cells... PROKARYOTES and EUKARYOTES

Prokaryotes and Eukaryotes

Prokaryotes

lack any internal membranes only the kingdoms bacteria and

archaebacteria are prokaryotes

Eukaryotes

have many internal membrane structures: nucleus-contains genetic material other organelles ('small organs')

Both Prokaryotes and Eukaryotes are Basically Alike

both have outer membranes both carry out the 7 life functions

Prokaryote

Eukaryote Unicellular Multicellular

Archaebacteria

Bacteria

Protist

Fungi

Plant

Animal

Comparing Prokaryotes and Eukaryotes

Prokaryotes Eukaryotes

Cell Membrane

Contain DNA

Nucleus

Endoplasmic Reticulum

Golgi Body

Vacuoles

Lysosome

Mitochondria

Cytoskeleton

In cells, various specialized functions occur in specific places. These places are like small organs to the cell. They are called organelles!

They’re likemini-organs!

Different Cell Parts Do Different Jobs

Organelles allow the cell to do 3 main jobs make energy

need energy for all activities need to clean up waste produced

while making energy make proteins

proteins do all the work in a cell, so we need lots of them

make more cells for growth to replace damaged or diseased

cells

Our organellesdo all these

jobs!

Different Cell Parts Do Different Jobs

Making energy to fuel daily life & growth, the cell must…

take in food & digest it take in oxygen (O2) make ATP remove waste

organelles that do this work… cell membrane lysosomes vacuoles & vesicles mitochondria chloroplast (plant cells only)

Function separates cell from outside controls what enters or leaves cell

O2, CO2, food, H2O, nutrients, waste recognizes signals from other cells

allows communication between cells

Structure double layer of fat

phospholipid bilayer receptor molecules

proteins

“protein ice bergs floating in a fatty sea”

lipid “tail”

phosphate“head”

Function digest food

used to make energy clean up & recycle

digest broken organelles Structure

membrane sac of digestive enzymes

Function moving material around cell storage – plants store more, so they have

larger vacuoles. Structure

membrane sac

Function make ATP energy from cellular respiration

sugar + O2 ATP fuels the work of life

Structure double membrane

Mitochondria make energy from sugar + O2

cellular respiration sugar + O2 ATP

Chloroplasts make energy + sugar from sunlight

photosynthesis

sunlight + CO2 ATP & sugar ATP = active energy sugar = stored energy

build leaves & roots & fruit out of the sugars

ATP

sugar

ATP

Making proteins to run daily life & growth, the cell must…

read genes (DNA) build proteins

structural proteins (muscle fibers, hair, skin, claws) enzymes (speed up chemical reactions) signals (hormones) & receptors

organelles that do this work… nucleus ribosomes endoplasmic reticulum (ER) golgi apparatus

cellsDNA proteins

one of the major job of cells is to make proteins,because…

one of the major job of cells is to make proteins,because…

proteins do all the work!proteins do all the work!

signals

structural

enzymes

receptors

Function control center of cell protects DNA

instructions for building proteins Structure

nuclear membrane nucleolus

ribosome factory chromosomes

DNA

Function protein factories read instructions to build proteins from DNA

Structure some free in cytoplasm some attached to ER

Function works on proteins

helps complete the proteins after ribosome builds them

makes membranes Structure

rough ER ribosomes attached works on proteins

smooth ER makes membranes

transport vesicles

vesiclescarrying proteins

Function finishes, sorts, labels & ships proteins

like UPS headquarters shipping & receiving department

ships proteins in vesicles “UPS trucks”

Structure membrane sacs

DNA

RNA

ribosomes

endoplasmicreticulum

vesicle

Golgi apparatus

vesicle

proteinon its way!

protein finishedprotein

Making Proteins

TO:

TO:

TO:

nucleus

TO:

Making more cells to replace, repair & grow,

the cell must… copy their DNA make extra organelles divide the new DNA & new

organelles between 2 new “daughter” cells

organelles that do this work… nucleus centrioles

Function help coordinate cell division

only in animal cells Structure

one pair in each cell

cell membranecell boundarycontrols movementof materials in & out

recognizes signals

cytoplasmjelly-like material holding organelles in place

mitochondriamake ATP energy

from sugar + O2

nucleusprotects DNAcontrols cell

ribosomesbuilds proteins

ERhelps finish proteinsmakes membranes

Golgi apparatusfinishes, packages & ships proteins

lysosomefood digestiongarbage disposal &recyclingvacuole & vesicles

transport inside cellsstorage

centriolescell division

central vacuolestorage: food, water or waste

mitochondriamake ATP in cellular respiration

chloroplastmake ATP & sugars in photosynthesis

cell wallsupport

cell membranecell boundarycontrols movementof materials in & out

recognizes signals

Golgi apparatusfinish & ship proteins

nucleuscontrol cellprotects DNA

endoplasmic reticulumprocesses proteinsmakes membranes

lysosomedigestion & clean up

ribosomesmake proteinscytoplasm

jelly-like material around organelles

nucleolusmake ribosomes

Cells have 3 main jobs make energy make proteins make more cells

Comparing Plant and Animal Cells

Plant Cell Animal Cell

Cell Membrane

Nucleus

Endoplasmic Reticulum

Golgi BodyVacuoles

LysosomeMitochondria

Cytoskeleton

CentriolesCell Wall

Chloroplasts Ribosomes

Cell Wall

Chloroplasts Ribosomes

Cell Wall

Chloroplasts

Endoplasmic Reticulum

Ribosomes

Cell Wall

Chloroplasts Lysosome

Centrioles

Lysosome

Viruses

Viruses

are not cells! viruses can NOT carry out most life

functions, however...they can REPRODUCE

reproduction of viruses can only happen inside a host cell!

viruses, along with bacteria (cells), fungi (cells), and other parasites can infect plants and animals and interfere with normal life functions! ex. influenza, HIV, chicken pox, polio,

smallpox (gone!), viral pneumonia

Movies for cytology packet\Tim & Moby discuss viruses.htm