Cell Organelles and Functions

Outside the Cell - Cell Wall Made of cellulose Freely permeable to

water and most solutes

Only in Plant cells Maintains cell turgidity Provide mechanical

support Protect from

mechanical damage

Extensions of the cell – Cilia / Flagella

Used for movement

Cilia are tiny hair-like projections

Flagella are long tail-like projection

Arrangement of microtubules

Holding it all together - Cell Membrane Phospholipid bilayer

containing proteins, cholesterol and carbohydrates

Separates cell contents from the environment; regulates movement of substances into and out of the cell

The Fluid within - Cytoplasm Fluid that

encompasses the inside of the cell’s membrane and outside the nucleus

Site of many chemical reactions

Give cell its structure Where the organelles

are located

Organelles in the Cytoplasm (eukaryote) - Nucleus

Membrane Bound spherical structure

Control centre of the cell

contains the genetic material

In the Nucleus-(eukaryote) Chromatin/Chromosomes

Threadlike Deoxyribonucleic Acid (DNA) and associated proteins

Genetic Material Also goes by the name

chromosomes, sister chromatids at various stages of cell life

In the Nucleus (cont’d) Nucleolus

Dense, spherical structure; composed of DNA, RNA and protein

Site of ribosome synthesis

Around the Nucleus – Nuclear Membrane

Phospholipid - protein bilayer; contains pores

Controls what enters and leaves the nucleus

Organelles in the Cytoplasm -Endoplasmic Reticulum (ER)

Membrane bound channels running throughout the cell

Network of channels

*Rough ER

Ribosomes attached to outside

Involved in protein synthesis and transportation of molecules

*Smooth ER

Ribosomes NOT attached to outside

Synthesis of lipids and transportation of molecules in the cell

Organelles in the Cytoplasm - Golgi Apparatus/bodies

Flattened, membrane bound, fluid filled disks, with associated vesicles surrounding the disks

Involved in the packaging of proteins, lipids and carbohydrates

Organelles in the Cytoplasm - Ribosomes

Small spherical bodies free floating in the cytoplasm or attached to ER

Composed of ribosomal RNA and protein

Site of protein synthesis

Organelles in the Cytoplasm -Lysosome Membrane bound

spherical sacs, containing enzymes

pH of approx. 5 Site of digestion and

storage of digestive enzymes

Can destroy harmful invaders to the cells

Organelles in the Cytoplasm -Vacuole

Membrane bound, fluid-filled sacs

Storage of food or water

In plants, involved in turgor pressure

Organelles in the Cytoplasm -Centriole Paired cylindrical

structures, composed of protein

Found only in Animal Cells

Assist in cell reproduction by producing spindle fibres (a type of microfilament)

Assists in the formation of cilia and flagella

Organelles in the Cytoplasm –Chloroplasts (next unit)

Used for absorption of light

Only in plants Site of

photosynthesis A series of chemical

reactions resulting in the production of glucose and ATP from sunlight and other raw materials

Mitochondria (next unit)

Membrane bound, bean shaped

mostly protein, but also contain lipids, DNA and RNA

Mitochondrial DNA is passed down from the mother only

Site of Aerobic Metabolism

Releases energy from food in the form of ATP