Cell Structures, Functions and Transport

Types of Cells Prokaryotic cells Eukaryotic cells

Prokaryotic cells Simplest cells No membranes around their

nuclear material (DNA and RNA, genetic material)

Prokaryotes include bacteria and some pond scum

Eukaryotic cells Eukaryotic cells have membranes

around their nuclear material Membrane bound organelles Eukaryotes include protists, fungi,

plants, and animals (almost all organisms)

Section 7-2

Figure 7-5 Plant and Animal Cells

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Animal Cell

Section 7-2


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Animal Cell

Cell Membrane

Cell membrane

Eukaryotic Cell Organelles and Function

1. Cell Membrane Nickname: “The Gatekeeper” Function: forms outer boundary of

the cellallows only certain

materials tomove into and out of the

cell

Parts: made up of a double layer of fats with some proteins scattered

throughout

Section 7-2


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Animal Cell

Cell Membrane

Cytoplasm

Cell membrane

Cytoplasm


2. Cytoplasm Gel-like material inside the cell

membrane and outside the nucleus Function: contains water, chemicals,

and the various cell organelles Cytoplasm constantly moves or

streams

Section 7-2


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Animal Cell

NucleusNucleolus

Cell Membrane

Cytoplasm

Nuclear Membrane

Cell membrane

Cytoplasm

NucleusNucleolus

Nuclear envelope/membrane


3. Nucleus Nickname: “The Control Center” Function: holds the DNA Parts:

1. Nucleolus: dark spot in the middle of the nucleus that helps make ribosomes

2. Nuclear envelope/membrane: surrounds nucleus in eukaryotic cells, has pores to let material in and out of the nucleus


3. Nucleus Parts:

3. Chromatin: Strands of genetic material found in the nucleus, made of protein and DNA

Section 7-2

Figure 7-5 Plant and Animal CellsAnimal Cell

NucleusNucleolus

MitochondriaCell Membrane

Cytoplasm

Nuclear Membrane

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria


8. Mitochondria Nickname: “The Powerhouse” Function: Energy formation

Breaks down food to make ATP ATP: is the major fuel for all cell

activities that require energy

Section 7-2


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Animal Cell

NucleusNucleolus Ribosomes

Cell Membrane

Cytoplasm

Nuclear membrane

Ribosomes

Mitochondria

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes


4. Ribosomes Function: makes proteins Found in all cells, prokaryotic and

eukaryotic

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Animal Cell

NucleusNucleolus

Rough Endoplasmic Reticulum

Smooth Endoplasmic Reticulum

Cell Membrane

Cytoplasm

Ribosomes

Nuclear Membrane

Ribosomes

Mitochondria

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes




5. Endoplasmic Reticulum (ER) Nickname: “Roads” Function: The internal delivery

system of the cell

Endoplasmic Reticulum 2 Types:

1. Rough ER: Rough appearance because it has

ribosomes on its surface Function: helps make proteins, that’s

why it has ribosomes2. Smooth ER:

NO ribosomes Function: makes fats or lipids

Section 7-2


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Animal Cell

NucleusNucleolus



Ribosomes

Golgi Complex

Cell Membrane

CytoplasmRibosomes

Nuclear membrane

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes



Golgi Body


6. Golgi Complex (Golgi Body) Nickname: The shippers Function: packages, modifies, and

transports materials to different location inside/outside of the cell

Appearance: stack of pancakes Structure: stack of membrane-

covered sacs

Section 7-2


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Animal Cell

NucleusNucleolus



Ribosomes

Golgi Body

Cell Membrane

CytoplasmRibosomes

Nuclear Membrane Mitochondria

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes



Golgi Body

Lysosome


7. Lysosomes: circular, but bigger than ribosomes

Nickname: “Clean-up Crews” Function: to break down food into

particles the rest of the cell can use and to destroy old cells

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes



Golgi Body

Lysosome

Vacuole


9. Vacuoles Function: Help store things Vacuoles in animal cells are usually

small sacs

Animal Cell

NucleusNucleolus



Ribosomes

Golgi Bodies

MitochondriaCell Membrane

CytoplasmRibosomes

Nuclear Membrane

Centrioles

Cell membrane

Cytoplasm

NucleusNucleolus


Mitochondria

Ribosomes



Golgi Body

Lysosome

Centriole (only 1 is shown)


10. Centrioles Function: Help with cell division Only found in animal cells Look like two small bundles of

spaghettiarranged perpendicularto each other

Now let’s talk about structures only found in PLANT Cells!!

Section 7-2


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Plant Cell

Cell Membrane

Vacuole


11. Vacuoles Function: stores water

This is what makes lettuce crisp When there is no water, the plant wilts

Animal cells have vacuoles to provide temporary storage

Vacuoles in animal cells are smaller than plant vacuoles

Vacuole

Section 7-2


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Plant Cell

Cell Membrane

Vacuole

Chloroplasts

Vacuole

Chloroplast


12. Chloroplasts Function: traps energy from the sun

to produce food for the plant cell Green in color because of

chlorophyll, which is a green pigment

Chloroplasts

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Plant Cell

Cell Membrane

Vacuole

Chloroplasts

Cell Wall

Cell wall


13. Cell Wall Function: provides support and

protection to the cell membrane Found outside the cell membrane in

plant cells

Plant Cell

Cell Membrane

Vacuole

Chloroplasts

Cell Wall

Nucleolus

Nucleus

Rough ER

Smooth ER

Golgi Bodies

Mitochondria

Ribosomes

Cytoplasm

Rough ER

Nuclear Membrane

Cell wall

Cell membrane

Vacuole

NucleusNucleolus


Chloroplast

Mitochondria Golgi Bodies

Ribosomes

Smooth ER

Rough ER

Lysosome

Cytoplasm

Comparing Plant and Animal CellsPlant Animal

Comparing Plant and Animal CellsPlant Animal

Cell WallChloroplastsLarge vacuole

CentriolesSmall vacuole

Cell MembraneCytoplasmNucleusNucleolusNuclear membraneMitochondriaRibosomesRough Endoplasmic ReticulumSmooth Endoplasmic ReticulumGolgi BodiesLysosomesVacuoles

Cell Transport

It’s a question of control.

Who’s in control? Cells get nutrients, etc. from

environment Release waste into same

environment

Moving along…or not!

Selective permeability: property of a cell membrane which allows some materials to pass through while keeping others out.

Diffusion Molecules move constantly Move from crowded

conditions to less crowded conditions

Particles diffuse in liquids and in gases

Diffusion cont’d Equilibrium: molecules of a

substance are spread evenly throughout a space

Molecules continue to move during equilibrium

Osmosis—Diffusion of H2O The diffusion of water through

a cell membrane Most cells surrounded by

water molecules and contain water molecules

Osmosis Cont’d What happened to egg cells

in lab? If cells aren’t surrounded by

pretty pure water, they’ll lose the water.

No water molecules in corn syrup around eggs—so ….

Water tended to move out of the cells and dilute the corn syrup

Cells became shriveled and yolks became firm

Place eggs in pure water and the process is reversed

The eggs swell up and the yolks slosh around inside

Moving on… Particle movement across cell

membrane by diffusion is called passive transport because…

Cell doesn’t use energy to move the materials

Active transport: energy required to move large molecules through cell membrane

Need help of transport proteins

Active transport is required to move substances from where there are small amounts to where there are large amounts

Cell membrane Cell membrane is composed

of a double layer (bilayer) of phospholipids with protein molecules scattered throughout

Phospholipids make a bilayer with polar heads facing out and hydrophobic tails facing in

Cell membrane model

Lipids

Cell Structures, Functions and Transport

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