Biology (Cell organelle description and function) (Grade 11)

Cell membrane

Description

• has a semi permeable membrane

• has double phospholipid bilayer

• has hydrophobic tail (pointing to the inside of the cell)

• has a hydrophilic head (points to the external aqueous environment)

Functions

• Allows materials inside and outside the cell

• acts as a protective layer

• has proteins which act as receptor sites, transporter, and communication messengers

Found in both animal and plant cells

Cytoplasm

Description

• is a jelly-like substance

• covers most of the area in the cell and holds the organelles together

• contains mostly water and other proteins

Functions

• maintains an optimal environment for the cell

• provides suspension for the organelles in the cell

• Transport medium for nutrients

Found in animal and plant cells

Nucleus

Description

• is a round-structure that has pores and has a nuclear envelope around it

• contains the nucleolus

• contains chromosomes, which contain hereditary information (DNA)

Functions

• in charge of cell division

• allows materials through the pores

• is the control centre of the cell

Found in animal and plant cells

Vacuoles and Vesicles

Description

• They are huge in plant cells and small in animal cells

• fluid filled sacs inside the membrane

Functions

• Vesicles transport material in and out, while vacuoles hold materials

• Vacuoles hold water in plant cells and hold waste materials in animal cells

• Vacuoles maintain turgor pressure and Vesicles maintain buoyancy control

Found in both animals and plants

Mitochondrian

Description

• bean shaped and has folded layers inside

• has ribosomes and ATP synthesis products

Functions

• powerhouse of the cell

• handles cellular respiration (converting glucose + oxygen into Carbon dioxide + water)

• changes chemical energy into usable energy

• duplicates, replicates and transcribes DNA

Found in both animal and plant cells

lysosomes

Description

• Spherically shaped, smaller than the nucleus but larger than vesicles

• Contain lipid layer below membrane

Functions

• contains enzymes to digest efficiently and easily

• lets it contents out to surround foreign invaders and kill them

• they break down worn out cells (clean the cells)

Found in animal cells only

Golgi apparatus

Description

• stack of flattened membrane

Function

• sort and package protein given to them by the rough endoplasmic reticulum

• form lysosomes

• transport lipids

Found in both animal and plant cells

Smooth endoplasmic reticulum

Description

• doesn’t have ribosomes on the outside

• has network of tubules throughout the cell

Functions

• makes fat and oil

Found in both animals and plant cells

Rough endoplasmic reticulum

Description

• has ribosomes on the outside

• has network of tubes throughout the cell

Functions

• makes the protein for the rest of the cell (gives it to the golgi)

Found in both animal and plant cells

Ribosome

Description

• made up of RNA and proteins

• attached onto RER or found floating in the cytoplasm

Function

• uses mRNA to make protein

cytoskelton

Description

• network mesh of proteins

• made up micro tubules + micro filaments + intermediate micro filaments

Functions

• backbone of the cell (gives it the structure and shape)

• helps the cell move

• supports the cell during the division

Found in both animal and plant cells

cell wall

Description

• semi permeable

• has a rigid layer of cellulose (fiber)

Functions

• Strengths and protects the cell

• provides structure and support

Found in only plant cells

Chloroplast

Description

• oval shaped

• has chlorophyll, a green pigment found in plants

• has thylakoid

• double outer membrane

Functions

• performs photosynthesis (converting carbon dioxide + water + energy into glucose and oxygen)

Found in only plant cells

centrioles

Description

• barrel shaped

• appear in pairs, perpendicular to each other

• ring of micro tubules (part of cytoskeleton)

Functions

• create spindle fibers to pull chromosomes apart during mitosis

Found in animal and protists

Cilia/Flagella

Description

• are tiny hair-like projections

• contain micro-tubules

• extend from the plasma membrane

Function

• used for movement

Found in animals, protists, fungi, and low level plants