The Cell

What is a cell?

The basic unit of life

All living thing are composed of one or more cells

Uni cellular organisms

Are made up of a single cell and carry out all necessary life processes within and by that cell. They are small in size and have a short life span.

Multi cellular organism

Are composed of multiple cells that work collaboratively to perform various functions, allowing for greater complexity and size and longer life spans.

Types of microscope 

Light microscope used to view cell microstructure 

Electron microscope used to view cell ultrastructure

Parts of light microscope

Eyepiece lens

Objective lens

Stage/platform

Condenser

Diaphragm

Light

Coarse focus

Fine focus

Magnification Triangle

magnification: image size divided by actual size of object

actual size of object: image size divided by magnification

image size: actual size of object multiplied by magnification

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Cell Ultrastructure

The detail that can be seen using an electron microscope

Plasma membrane (Cell membrane)

Keeps the cell contents enclosed

It is composed of phospholids and proteins

Phospholids 

Phosphate head- water loving 

Lipid- water hating

These are arranged in double layer, the proteins are embedded in the layers.

Draw animal cell ultrastructure

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Draw plant cell

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Cell Wall  

Only in plant cells

Made up of cellulose (carbohydrate) and is permeable to water and solutes 

Prevents lysis

Gives the plant extra protection and support

Cytoplasm

The liquid that surrounds the nucleus

It is a sticky liquid in which the cell organelles are suspended

Mitochondria

Powerhouse of cell

Easily recognized by the folding of the inner membrane

Supplies cell with energy

The site of respiration

Found in large amounts in muscle cells (animal cells) and meristem (plant cells), fat cells need fewer mitochondria

Mitochondria diagram

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Nucleas

Brain of cell

Controls cell activity

Contains DNA

Nuceolus + Ribosomes

The area in the nucleus where ribosomes are made

Composed of ribosomal RNA and protein

Involved in the making of protein

Chloroplast

Only present in plants

Green structure where photosynthesis takes place 

They contain the green pigment, chlorophyll

Chloroplast diagram

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Vacuole

Only found in cell structures

Large sack like structure

Stores water, sugar, starch, amino acids and wastes

Involved in elongation (growth)

Organelles only found in plant cells

Cell wall

Vacuole 

Chloroplast 

Endoplasmic Return

Smooth ER- does not have any ribosomes attached to it. Forms many proteins, stores calcium and breaks down poisons

Rough ER-has ribosomes attached to the outer side. Produces and transports protein and new membrane

Golgi apparatus

Made up of flattened membrane sacks

Makes, stores and transports molecules

Prokaryotic

Do not have a nucleus or membrane enclosed organelles 

Are small and more primitive 

Are found in bacteria 

Eukaryotic

Have a membrane enclosed nucleus and cell organelles 

Are larger and more advanced 

Are found in plant and animal cells