Cell Structure Function Cell Theory 1 All living

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Cell Structure & Function

Cell Structure & Function

Cell Theory 1. All living things are made of cells 2. Cells are the

Cell Theory 1. All living things are made of cells 2. Cells are the basic unit of life 3. All cells come from pre-existing cells

What do all cells have in common? 1. Genetic information (DNA) 2. Cytoplasm –

What do all cells have in common? 1. Genetic information (DNA) 2. Cytoplasm – fluid-filled region between center and cell membrane

What do all cells have in common? 3. Cell membrane (plasma membrane) – surrounds

What do all cells have in common? 3. Cell membrane (plasma membrane) – surrounds cell ◦ Function: regulates what enters and leaves cell 4. Ribosomes – make proteins using instructions from DNA

How big is a cell? Animation – Cell Size

How big is a cell? Animation – Cell Size

Surface Area to Volume Ratio • Why are cells so small? • Ratio of

Surface Area to Volume Ratio • Why are cells so small? • Ratio of surface area to volume • Much greater for small cells • Space is important for cells to receive nutrients, oxygen, and to remove waste • Volume increases faster than surface area as cells grow • Greater volume= more metabolic reactions BUT more difficult to transport wastes and nutrients • The smaller the cell, the more efficient it is to transport materials across it

Organisms can be: o Unicellular o Consist of only 1 cell o Multicellular o

Organisms can be: o Unicellular o Consist of only 1 cell o Multicellular o Consist of multiple cells

2 Basic Cell Types PROKARYOTIC EUKARYOTIC

2 Basic Cell Types PROKARYOTIC EUKARYOTIC

Prokaryotic • Smaller/unicellular • Simple • No organelles • No nucleus • Ex: Bacteria

Prokaryotic • Smaller/unicellular • Simple • No organelles • No nucleus • Ex: Bacteria

Eukaryotic • Larger-multi or unicellular • More complex • Many organelles • Structures that

Eukaryotic • Larger-multi or unicellular • More complex • Many organelles • Structures that have a specific function; “miniorgans” • Nucleus – encloses DNA • Control center of the cell

Eukaryotic o. Ex: Plants, animals, fungi, protists o. Unicellular eukaryotes = Protists

Eukaryotic o. Ex: Plants, animals, fungi, protists o. Unicellular eukaryotes = Protists

Unicellular Eukaryote. Protists Why are protists eukaryotes if they are only made up of

Unicellular Eukaryote. Protists Why are protists eukaryotes if they are only made up of ONE cell? Amoeba Paramecium Dinoflagellates

Prokaryote vs. Eukaryote -What is different between the two types of cells?

Prokaryote vs. Eukaryote -What is different between the two types of cells?

Prokaryotes • Simple internal structure • Nucleoid Region (no nucleus) • Flagellum → whiplike

Prokaryotes • Simple internal structure • Nucleoid Region (no nucleus) • Flagellum → whiplike tail used for movement

Prokaryotes o. Pili – short projects that help bacteria attach to surfaces o. Most

Prokaryotes o. Pili – short projects that help bacteria attach to surfaces o. Most primitive organisms

Bacteria E. Coli Strepococcus mutans

Bacteria E. Coli Strepococcus mutans

Bacteria Staphylococcus aureus Mycobacterium tuberculosis

Bacteria Staphylococcus aureus Mycobacterium tuberculosis

Cell Organelles and Functions EUKARYOTIC CELLS INTERNAL STRUCTURE

Cell Organelles and Functions EUKARYOTIC CELLS INTERNAL STRUCTURE

Eukaryotes CAN BE SPLIT INTO PLANT AND ANIMAL CELLS

Eukaryotes CAN BE SPLIT INTO PLANT AND ANIMAL CELLS

Animal Cell

Animal Cell

Animal Cell

Animal Cell

Plant cell

Plant cell

Nucleus o. Function: Control center of the cell o. Eukaryotic cells ONLY!!!

Nucleus o. Function: Control center of the cell o. Eukaryotic cells ONLY!!!

Nucleus 3 parts: ◦ 1. Contains DNA ◦ A. Chromosome – DNA coiled around

Nucleus 3 parts: ◦ 1. Contains DNA ◦ A. Chromosome – DNA coiled around proteins called histones ◦ Humans contain 46 chromosomes in nucleus of all cells ◦ Exceptions: Red blood cells (no nucleus), sex cells ◦ B. Chromatin – uncoiled DNA; DNA usually found in this form

Nucleus 2. Nuclear envelope (nuclear membrane) – membrane w/ pores to allow materials in

Nucleus 2. Nuclear envelope (nuclear membrane) – membrane w/ pores to allow materials in and out of the nucleus 3. Nucleolus – inside the nucleus; makes ribosomes

Cytoplasm o. Organelles can be found in the cytoplasm o. Cytoplasm- portion of the

Cytoplasm o. Organelles can be found in the cytoplasm o. Cytoplasm- portion of the cell outside of the nucleus

Endoplasmic Reticulum(ER) Folded membranes attached to nucleus Smooth ER → ◦ Not lined with

Endoplasmic Reticulum(ER) Folded membranes attached to nucleus Smooth ER → ◦ Not lined with ribosomes ◦ Synthesizes lipids ◦ Detoxifies chemicals (i. e. liver)

Rough ER ◦Lined with ribosomes ◦Function: Modifies proteins that are being transported Ribosomes- made

Rough ER ◦Lined with ribosomes ◦Function: Modifies proteins that are being transported Ribosomes- made of RNA & protein - Function: Assemble proteins based on instructions from DNA

C 4 U Difference between Rough and smooth ER What are ribosomes? Where can

C 4 U Difference between Rough and smooth ER What are ribosomes? Where can they be found?

Golgi apparatus (golgi body) Looks like a flattened stack of pancakes Functions: ◦ Receives

Golgi apparatus (golgi body) Looks like a flattened stack of pancakes Functions: ◦ Receives vesicles (sacs) from the ER and finishes, sorts, and ships protein ◦ “Packages protein” One side = receiving; other side = shipping

Lysosomes • Lysosome – Function: Contains powerful digestive enzymes • Digests food particles to

Lysosomes • Lysosome – Function: Contains powerful digestive enzymes • Digests food particles to release nutrients to cell Fun Fact enzyme in lysosome destroys skin between fingers/toes during embryo development

Lysosomes ◦“Demolition/cleanup crew” ◦Destroys damaged organelles ◦Ex: neutrophils (WBC) engulf bacteria ◦Produced by the

Lysosomes ◦“Demolition/cleanup crew” ◦Destroys damaged organelles ◦Ex: neutrophils (WBC) engulf bacteria ◦Produced by the Golgi

Peroxisomes • Functions: • Breakdown fatty acids, H 2 O 2 (catalase), synthesis of

Peroxisomes • Functions: • Breakdown fatty acids, H 2 O 2 (catalase), synthesis of myelin (for nerve cells) • Produced by the ER • Disease: ALD – caused by peroxisome not functioning properly

Inside the cell WORKING AS A TEAM

Inside the cell WORKING AS A TEAM

Vacuoles Function: Storage “containers” ◦ store various substances Animals = small and numerous Plants

Vacuoles Function: Storage “containers” ◦ store various substances Animals = small and numerous Plants = one large central vacuole ◦ Stores mostly water ◦ Helps with the structure of a plant cell

Central Vacuole • Also functions as a large lysosomecontains enzymes which break down materials

Central Vacuole • Also functions as a large lysosomecontains enzymes which break down materials • Increases turgor pressure (internal cell pressure)

Turgor Pressure Cell swells due to influx of water Cell shrinks due to water

Turgor Pressure Cell swells due to influx of water Cell shrinks due to water loss

Vacuoles Contractile vacuole → gets rid of excess water; found in some protists ◦

Vacuoles Contractile vacuole → gets rid of excess water; found in some protists ◦ Prevents bursting of cell & dilution

Energy Organelles CHLOROPLAST • Plants only • Some protists and algae • Function: •

Energy Organelles CHLOROPLAST • Plants only • Some protists and algae • Function: • Site of photosynthesis • Use sun energy to make food energy

Energy Organelles MITOCHONDRIA • All eukaryotes • Function: • Site of cellular respiration •

Energy Organelles MITOCHONDRIA • All eukaryotes • Function: • Site of cellular respiration • Creates energy for cell (ATP) from food

Mitochondria • Contain 2 membranes • Outer membrane • Inner membranefolded up inside the

Mitochondria • Contain 2 membranes • Outer membrane • Inner membranefolded up inside the organelle

Plant cells ONLY! o. Cell Wall o. Function: Rigid layer to protect and support

Plant cells ONLY! o. Cell Wall o. Function: Rigid layer to protect and support cell o. Keeps cell from bursting o. Made of cellulose (carbohydrate) o. Chloroplasts – used for photosynthesis o. Large central vacuole

Plant Cell

Plant Cell

Cytoskeleton - network of protein filaments (fibers) that help the cell maintain its shape

Cytoskeleton - network of protein filaments (fibers) that help the cell maintain its shape • Function: Helps with support/internal structure and movement • Like wood and nails of house

Cytoskeleton

Cytoskeleton

Cytoskeleton • Made up of microfilaments and microtubules

Cytoskeleton • Made up of microfilaments and microtubules

Microfilaments ◦Made of solid globular protein called actin ◦Used for movement and supports shape

Microfilaments ◦Made of solid globular protein called actin ◦Used for movement and supports shape ◦Ex: Muscle contractions

Intermediate Filaments ◦Made of fibrous proteins ◦They reinforce cell shape and anchor organelles ◦Ex:

Intermediate Filaments ◦Made of fibrous proteins ◦They reinforce cell shape and anchor organelles ◦Ex: Holds nucleus in place

Microtubules ◦ Hollow tubes of protein called tubulin ◦ They often disassemble and reassemble

Microtubules ◦ Hollow tubes of protein called tubulin ◦ They often disassemble and reassemble ◦ Helps with movement) ◦ Ex: lysosome may slide along to reach food ◦ Ex: movement of chromosomes when cells divide

Movement Both made of microtubules wrapped in membrane Cilia → short and numerous; beat

Movement Both made of microtubules wrapped in membrane Cilia → short and numerous; beat together ◦ Ex: Cells of human windpipe sweep pollen & mucous containing debris from lungs Flagella → few; long and whip-like ◦ Ex: sperm cells

Centrioles • Type of microtubule • Function: Organize DNA during cell division • ONLY

Centrioles • Type of microtubule • Function: Organize DNA during cell division • ONLY IN ANIMAL CELLS

PLANT BOTH ANIMAL

PLANT BOTH ANIMAL

Use these terms to fill in your Venn Diagram Cell membrane Golgi body Rough

Use these terms to fill in your Venn Diagram Cell membrane Golgi body Rough & smooth ER Mitochondria Nucleus Cytoskeleton Ribosomes Central vacuole Chloroplast Lysosome Centrioles Cell Wall Small vacuoles