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Cells &

Organelles

Cell:

Smallest unit of life that

can carry out all of the

functions of a living

thing.

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The Cell Theory

1. All living things are composed of cells.

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

3. New cells are produced from existing cells.

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Two Types of Cells

Prokaryotes

� Pro-: before; -karyote: nucleus

� Very small and simple

� No defined Nucleus

� No membrane-bound

organelles

� Kingdoms Found in:

� Bacteria

� Archaea

Eukaryotes

� Eu-: true; -karyote: nucleus

� Larger

� Contain defined Nucleus

� Contain membrane-bound

organelles

� Kingdoms Found in:

� Animalia

� Plantae

� Protista

� Fungi

Prokaryotes vs. Eukaryotes

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Unicellular vs. Multicellular

Organisms

Unicellular

� Uni-: one; -cellular: cell

� Composed of one cell

� Ex. Bacteria

Multicellular

� Multi-: many; -cellular: cell

� Composed of two or more cells

� Ex. Plants, Animals

Cell Size

� Vary greatly

� 8,000 of smallest bacteria can fit into 1 red blood cell

� Nerve cells can be >1 meter long

� Ostrich Egg has a volume of 1 L

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Cell Shape

� Size is always related to function

� Ex. Nerve cells are very long – Why?

� Ex. Red blood cells are round – Why?

� Ex. Amoeba shape changes – Why?

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Cell Organelles

� Two Word Definition:

� Little Organs

� Specialized structure that performs important cellular

function

� Helps the cell do different jobs

� Each organelle has its own purpose which is very specific

Animal Cell

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Plant Cell

Animal Cells Plant Cells--- Cell Wall

Cell Membrane Cell Membrane

Cytoplasm Cytoplasm

Nucleus Nucleus

Nucleolus Nucleolus

Mitochondria Mitochondria

Endoplasmic Reticulum Endoplasmic Reticulum

Golgi Bodies Golgi Bodies

Lysosomes Lysosomes

Ribosomes Ribosomes

Centrioles Centrioles

Cilia Cilia

Flagella Flagella

--- Chloroplast

--- Chromoplast

--- Leucoplast

--- Vacuole

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Organelle: Cell Membrane

� Two Word Definition:

� Selectively permeable

� Function:

� Regulates what enters and leaves the cell (like a fence with gates)

� Provides protection and support for the cell

Organelle: Cell Membrane

� Structure:

� Complex structure arranged in a double-layered sheet known as a lipid bilayer

� “Fluid Mosaic Model” – flexible lipid bilayer structure with proteins and carbohydrates embedded within the layers

Protein Gate

Lipid Bilayer

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Organelle: Cell Membrane

Cell Membrane taken with a TEM

Egg

Demonstration

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Solution Review

Solution Review

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Organelle: Cell Wall

� Two Word Definition:

� Support & Structure

� Function:

� Provide support and protection for the cell

Organelle: Cell Wall

� Structure:

� Composed mainly of Cellulose (carbohydrate fiber)

� More rigid than cell membrane

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Organelle: Cytoplasm

� Two Word Definition:

� Cell Fluid

� Function:

� Allows movement of materials built inside the cell

� Medium for the organelles to sit/float in

Organelle: Cytoplasm

� Structure:

� Semi-fluid substance made of water, proteins, lipids, and other chemicals

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Organelle: Nucleus

� Two Word Definition:

� Control center

� Function:

� Stores the cell’s DNA

� DNA: Instructions for making proteins

� Control different activities in the cell

Organelle: Nucleus

� Structure:

� Surrounded by a double-layered membrane, called the Nuclear Envelope, which contain thousands of holes, called Nuclear Pores.

� These pores let messages in and out of the nucleus.

� Inner fluid is called Nucleoplasm (like cytoplasm in the nucleus)

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Organelle: Nucleus

Organelle: Nucleolus

� Two Word Definition:

� Makes Ribosomes

� Function:

� Assemble the ribosomesneeded for the cell

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Organelle: Nucleolus

� Structure:

� Dense “knot” of chromatin

� There can be more than one in the nucleus.

Nucleolus

Organelle: Mitochondria

� Two Word Definition:

� Cell Powerhouse

� Function:

� Site of Cellular Respiration

� Food ���� Energy

� Makes “ATP”

� ATP = cell energy

� Like our battery back (energy reserve)

� Trivia: We use 1 billion ATPs / 2 minutes

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Organelle: Mitochondria

� Structure:

� Kidney bean shape

� Two Regions in the Interior:

� Cristae: inner folded membrane

� Matrix: inner fluid

Organelle: Mitochondria

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Organelle: Mitochondria

Organelle: Endoplasmic Reticulum

� Two Word Definition:

� Transport & Storage

� Prefix/Suffix:

� Endo- = inside

� Plasma = fluid

� Reticulate = repeated patterns

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Organelle: Endoplasmic Reticulum

� Two Types of Endoplasmic Reticulum (ER):

� Rough Endoplasmic Reticulum (ER)

� Smooth Endoplasmic Reticulum (ER)

Organelle: Rough ER

� Function:

� Transports and stores proteins

� Structure:

� Covered in Ribosomes (like spots)

� Connected to the nuclear membrane

� Network of channel-like membranes

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Organelle: Smooth ER

� Function:

� Transports and stores lipids & detoxifying drugs

� Structure:

� NO Ribosomes (smooth surface)

� Connected to the nuclear membrane

� Network of channel-like membranes

Organelle: Endoplasmic Reticulum

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Organelle: Golgi Apparatus

� Multiple Names:

� Golgi Apparatus

� Golgi Body

� Golgi Complex

� Mr. Camillo Golgi

� Discovered the Golgi Apparatus in 1898!

� Won the 1906 Nobel Prize for nervous system research

Organelle: Golgi Apparatus/Body

� Two Word Definition:

� Packaging Center

� Function:

� Modifies, sorts, and packages protein vesicles made in the “ER”

� These vesicles will leave the cell

� Makes lysosomes

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Organelle: Golgi Apparatus/Body

� Structure:

� Flattened stack of membranes

� Like a “pancake stack”

Transport

Vesicle

from ER

New Vesicle

forming

Transport Vesicle

from Golgi

Organelle: Golgi Apparatus/Body

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Org

an

elle

: Go

lgi

Ap

pa

ratu

s/Bo

dy

Organelle: Lysosomes

� Structure:

� Membrane sac filled with hydrolytic enzymes

� Made by the Golgi Apparatus

� Two Word Definition:

� Suicide Sacs

� Function:

� Contain enzymes used to breakdown/destroy materials inside and outside of the cell

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Organelle: Lysosomes

Formation of Lysosomes by the Golgi Apparatus

Vesicle containing

hydrolytic enzymes is

pinched off the Golgi

and begins journey to

cell membrane.

Organelle: Ribosomes

� Two Word Definition:

� Protein Synthesis

� Function:

� Site of the construction of proteins

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Organelle: Ribosomes

� Structure:

� Made of rRNA

� Made of 2 interlocking parts (“subunits”)

� Ribosomes are found in two locations:

� Free ribosomes (“floaters”)

� Ribosomes connected to Rough ER

Organelle: Ribosomes

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Organelle: Ribosomes

Organelle: Chromosomes

� Two Word Definition:

� Hereditary Information

� Genetic Mailman

� Function:

� Code for all the organisms’ traits

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Organelle: Chromosomes

� Structure:

� Composed of DNA and proteins

� When cell is at rest, DNA is known as “chromatin”

Organelle: Chromosomes

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Organelle: Cilia

� Two Word Definition:

� Short/Fast Movement

� Function:

� Locomotion

� Structure:

� Short, hair-like structures

� 9+2 arrangement of microtubules

Organelle: Flagella

� Two Word Definition:

� Long/Slow Movement

� Function:

� Locomotion

� Structure:

� Long, hair-like structures

� Flagella whips around for movement

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Cilia & Flagella Videos

� https://www.youtube.com/watch?v=QGAm6hMysTA

Organelle: Centrioles

� Two Word Definition:

� Cell Division

� Function:

� Makes spindle fibers

� Spindle fibers: protein

structure that divides

genetic material in the cell

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Organelle: Centrioles

� Function:

� Centrioles produce spindle fibers during cell division

� As cell division begins centrioles move to opposite ends of the

cell

� Once positioned centrioles will produce spindle fibers

Organelle: Centrioles

� Structure:

� Made of microtubules of contractile proteins

� Tubules are in a 9x3 arrangement

� Centrioles are located at right angles to each other OUTSIDE of the cell nucleus

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Organelle: Chloroplast

� Two Word Definition:

� Photosynthesis

� Function:

� Site of photosynthesis reactions

� Conversion of light energy to chemical energy

Organelle: Chloroplast

� Structure:

� Similar appearance to mitochondria

� Two Main Regions:

� Stroma: fluid

� Grana: stacks of chlorophyll discs

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Organelle: Chloroplast

Stroma = Fluid environmentGranum (-a) = chlorophyll storage

Organelle: Chloroplast

Relation of Structure to Function:

Sunlight energy is

absorbed by the

chlorophyll.

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Organelle: Chromoplast

� PLANTS ONLY!

� Two Word Definition:

� Color Storage

� Color Bodies

� Function:

� Coloration of flowers,

fruits, and leaves

� Structure:

� Membrane sacks filled with non-green pigments in plants

Organelle: Leucoplast

� PLANTS ONLY!

� Two Word Definition:

� Starch Storage

� Function:

� Starch Storage

� Structure:

� Membrane sack filled with starch

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Organelle: Vacuole

� Two Word Definition:

� Water/food Storage

� Function:

� Food and water

storage center inside

the cell.

� Structure:

� Similar to a water balloon

Organelle: Vacuole

- One cell organisms “stomach.”

- Function of water vacuole in plants is to provide

tugor pressure which keeps plants upright.