updated the cell factory ppt

THE CELL

Chapter 7

Microscopy Micrographs

Photograph of the view through a microscope Light Microscopes Electron Microscopes

Scanning EM To look at the surface of cells/specimen 3-D images

Transmission EM To look at internal structures of cells/specimen

Robert Hook (1665)

Englishman cork “cells” Compound

microscope

Anton van Leeuwenhoek (1660’S)

(LAY vun Hook)

Holland Single lens

microscope Pond water “animalcules”

Cell Theory

3 parts and key people

Cells

Basic units of life

Matthias Schleiden (1838)

German botanist Plant cells

Theodor Schwann (1839)

German biologist Animal cells

Rudolf Virchow (1855)

German physician New cells could only

come from the division of existing cells

Cell Theory

All living things are composed of one or more cells

Cells are the basic units of structure and function in living things

New Cells are produced from existing cells

Lots of different shapes and sizes of cells

Microscopes

Sizes The body is made of 100 trillion cell (1014) Extremely small…The human eye can

see .01 cm, a human cell is 5x smaller 5 to 50 micrometers…µm How big is a micrometer? 1m=100cm=1,000,000 micrometers 1 micrometer=.000001m Basically you can’t see it Remember: KHDmDCM..micro..nano..pico

Chaos chaos Largest protozoan You can see without

microscope 1000 micrometers How many meters is this?

.001 m How many centimeters is

this? 0.1 cm

2 things in every cell…

Surrounded by a barrier, cell membrane At some point in their life they contain….

DNA

What is a Nucleus? Plural: nuclei Large, membrane enclosed

structure that contains the cell’s genetic material in the form of DNA

What is a membrane? A thin layer of material that

serves as a covering or lining

2 categories for cells… Prokaryotes (pro-care-ee-

ohts) No nucleus Cell’s genetic material is

not contained in the nucleus…found in NUCLEOID:

Region in cytoplasm where DNA is found

Less complicated that eukaryotes

Some have internal membranes

Do NOT have membrane bound organelles

Carry out every activity associated with living things…which are…

Eukaryotes (you-care-ee-othts) Contain nucleus in which the

genetic material is separated from the rest of the cell

Contains dozens of structures and internal membranes

High Variety Single celled or multi-cellular Plants, animals, fungi, and protists

Eukaryotic cell structure

The Cell factory Organelles

Highly specialized structures within the cell Little organs

2 major divisions of the eukaryotic cell Nucleus

The “brain” DNA

Cytoplasm Portion outside the nucleus but inside the cell membrane

2 types of Eukaryotic cells Plant cells

Animal cells What are the differences? (write them down!!!)

Nucleus

Brain of the cell Office of the factory Contains nearly all the cell’s DNA and

with it the coded instructions for making PROTEINS and other important molecules

Nuclear envelope Surrounds nucleus Made of 2 membranes Dotted with thousands of nuclear pores

How do we get messages, instructions and blueprints out of the office?

Allow material to move in and out of nucleus by using “little runners” such as proteins, RNA and other molecules

Inside the nucleus we see…

Contain a granular material called… CHROMATIN

Chromatin= DNA + protein Usually spread out in nucleus During cell division, chromatin clumps

together or condenses…we call this…. CHROMOSOMES

In the nucleus…

Contain a granular material called… CHROMATIN

Chromatin= DNA + protein Usually spread out in nucleus During cell division, chromatin clumps

together or condenses…we call this…. CHROMOSOMES

Chromosomes

Threadlike structures that contain genetic information that is passed on from one generation to the next

Nucleolus

Small dense region inside the nucleus Function: assembly of ribosomes begin…

Ribosomes Most important function of cell is…

Making proteins Proteins regulate a zillion different things Like…

Proteins are assembled ON Ribosomes Ribosomes are small particles of protein &

RNA (what’s RNA?) They follow instructions from the nucleus to

make proteins…follow the orders from the “head haunchos” in the main office

Scattered throughout the cell They are like little factories If a cell’s main function is making proteins, how

many ribosomes are you going to have?

Endoplasmic reticulum (ER)

Internal membrane system The site where the lipid components of

the cell membrane are assembled, along with proteins and other materials exported from the cell

2 types Smooth ER Rough ER

Rough ER Involved in protein making (synthesis) So what are we going to see on it?

ribosomes Once a protein is made, it leaves the

ribosome and goes into the Rough ER The rough ER then modifies the protein All proteins that are exported by the cell

are made on the RER Membrane proteins are made on the

RER too

Smooth ER NO ribosomes on it Looks smooth Contains collections of ENZYMES that have

specialized tasks What do enzymes do?

Tasks include: Synthesis of membrane lipids Detoxification of drugs Liver cells

Big in detox therefore….what do u think liver cells have a lot of?

Golgi Apparatus Discovered by Italian scientist Camillo Golgi Once proteins are done being “modified” in the

RER, they move onto the Golgi apparatus Looks like a stack of pancakes Function: modify, sort, and package proteins

and other materials from the ER for STORAGE or SECRETION outside the cell Proteins are “shipped” to final destination

They are the CUSTOMIZATION SHOP Finishing touches on proteins before they leave

factory

Lysosomes (Lie-so-soh-mz) The factory’s clean-up crew It’s an Organelle filled with

enzymes Function: Digestion (break

down) of lipids, carbohydrates, and proteins into smaller molecules that can be used by the cell

Also digest organelles that have outlived their usefulness

What do you think happens if lysosomes malfunction?

A bunch of “junk” build up in the cell…why?

Is this good? Many human diseases result from

malfunction of lysosome Tay-Sachs disease DNA does not make the enzyme

hexoaminidase A that breaks down lipids in nerve cells

Build up of lipids in nerve cells causes those cells to stop working

Noticeable 3-6 months after birth, child lives to be about 4-5 years old

Vacuoles The factory’s storage place Only in certain cells Sac-like organelles Function: stores material such as water,

salts, proteins, and carbohydrates Plant cells have a single, large central

vacuole Pressure of central vacuole allows plants to

support heavy structures

Single-celled organisms and some animals also have vacuoles…

Paramecium Contractile vacuole Contracts rhythmically to pump excess water

out…this maintains what? homeostasis

What is the one thing all living things need to eat, breath, reproduce, move and much more?

ENERGY!!!!

Two ways cells get energy…

From food molecules From the sun

Mithochondria

Convert chemical energy stored in food into compounds that are more convienent for the cell to use

Has 2 membranes Inner membrane Outer membrane

In Animal AND Plant cells Nearly all come from the ovum

You get your mitochondria from your mom!

Mitochondria=LOTS of ATP Site of cell respiration Cell Respiration (REQUIRES

OXYGEN=AEROBIC)

3 stages of Cell respiration GLYCOLYSIS

Makes a lil’ bit of ATP Location: CYTOPLASM

KREBS CYCLE Makes a lil’ bit of ATP Location: MATRIX of

MITOCHONDRIA

ELECTRON TRANSPORT CHAIN Makes A LOT of ATP!!! Location: INNER MEMBRANE of

MITOCHONDRIA

No Oxygen= ANAEROBIC No oxygen available (or not enough) cell switches to

FERMENTATION Glycolysis over and over and over

Happens in CYTOPLASM Makes a Little Bit of ATP Lactic Acid Fermentation

Animals Muscle cells Only can use for a few seconds

Alcohol Fermentation Bacteria and Fungi Ex. yeast

Chloroplasts Plant and some Bacteria cells only ( NOT

in animal cells) Capture energy from the sunlight and

convert it into chemical energy…what is this process called? PHOTOSYNTHESIS

Like solar power for plants 2 membranes Inside: large stacks of other membranes

that contain chlorophyll

Organelle DNA Chloroplasts and

mitochondria contain their own genetic info In form of small, circular

DNA molecules mDNA

Lynn Margulis

American biologist Chloroplasts and

mitochondria are descendents of prokaryotes

She said… Ancient Prokaryotes from wayyyyy back in the

day had a symbiotic relationship with the ancient eukaryotes What is symbiotic? (review ecology!!!)

The prokaryotes lived inside the eukaryotes There were prokaryotes that used oxygen to

make energy (ATP) Mitochondria

There were prokaryotes that used photosynthesis to get energy Chloroplasts

Endosymbiotic Theory Idea that

mitochondria and chloroplasts evolved from prokaryotes

Cytoskeleton

Supporting structure and transportation system Network of protein filaments that helps

the cell to maintain its shape and to help the cell move

2 main type of filaments Microtubules Microfilaments(Intermediate filaments is a 3rd type)

Microfilaments

Threadlike structures Made of protein called ACTIN Extensive networks Tough, flexible framework Help cells move Assembly and disassembly helps cells

move (like amoebas)

Microtubules

Hollow structures Made of proteins called TUBULINS Maintain cell’s shape Important in cell division

Make mitotic spindle (separates chromosomes)

Help build projections from cell surface…

Cilia and Flagella Plural: cilium and flagellum Cilia: hundreds of extension of the cell membrane that move like

the oars of a boat Flagella: one or two long extensions off the cell that move in a

whip like fashion Enable cells to swim rapidly through liquid

Centrioles

Only animal cells Made of protein

TUBULIN What else is made of

tubulin?

Near nucleus Help organize cell

division

Antwon van Leeuwenhook Robert Hook Cell bacteria Cell Theory Electron microscope Prokaryote Eukaryote Organelles Cytoplasm Nuclear envelope Chromatin Nucleus nucleolus Ribosome Smooth ER Rough ER Chromosome Vacuole Osmosis Endocytosis exocytosis Proteins DNA RNA

Microscope Micrograph Magnifier Lens Contractile vacuole Central Vacuole Centrioles Centrosomes Nuclear pores Nuclear-plasm Stomata ATP synthase Chlorophyll Cell membrane Cell Wall Cellulose Phospholipids Thylakoid Cristae Matrix Inner membrane Outer memebrane

Golgi apparatus Micrometer Millimeter Picameter Lysosome Vacuole Mitochondria Chloroplast Cytoskeleton Centriole Mictrotubule Microfilament Theodor Schwann Matthias Schleiden Rudolph Virchow Lynn Margulis Endosymbiotic Theory Cilia Flagella Photosynthesis Pseudopodia Aquaporin Transmembrane protein Facilitated diffusion