Biology- Parts of the Cell

Cell Membrane

Location: Outer most boundary of the cell

Structure: Flexible phospholipid bilayer (2 layers)

Function: Supports cell and controls what enters/leaves the cell

Is" “semi-permeable” because some substances can easily pass through while others cannot

Cytoplasm

Location: Fills the cell

Structure: Clear jelly-like fluid

Mostly water

Function: Holds and cushions organelles and contains dissolved substances the cell stores until needed

Chemical reaction take place here

Nucleus

Location: Roughly in the center of the cell

Structure: Dark sphere surrounded by a nuclear envelope/membrane

Function: “Control centre” of the cell that manages all cell activities

Contains DNA (genetic material)

Nuclear membrane/envelope

Location: Surrounds the nucleus

Structure: Lipid-protein bilayer that contains pores

Function: Contains the contents of the nucleus and controls what enters and exits the nucleus

Nucleolus

Location: Inside the nucleus

Structure: Dense, round mass

Function: Site where ribosomes are made

RNA stored here

Vacuole

Location: In cytoplasm

Structure: Fluid-filled sac enclosed by a single layer membrane

More prominent in plant cells, while animal cells may have small ones

Function: In plants, they mainly store water to help maintain turgor pressure of cell

Storage unit for nutrients, water and other substances used by the cell

Plants need to store more energy than animals

Vesicle

Location: In cytoplasm

Structure: Membrane-bound (double layer) organelle

Function: Transports substances throughout cell

Mitochondria

Location: In the cytoplasm

Active cells (e.g. muscle) contain more than less active cells (e.g. fat cells)

Structure: Cylindrical structure

Double Membrane is folded

Function: “Powerhouse” of the cell

Carries out cellular respiration to convert glucose into usable energy 

Golgi Apparatus/ Body

Location: Close to the nucleus

In cytoplasm

Structure: Flattened bag-like membrane-bound sacs

Function: Collects and sorts

Lysosome

Location: In cytoplasm

Only in animal cells

Structure: Spherical organelles

Contains enzymes

Function: Digests food particles

Destroys harmful materials that enter the cell

Recycles old cell parts and dead cells to make other cells

Endoplasmic Reticulum (Rough, Smooth)

Location: Runs throughout the cytoplasm

Extends from nucleus to cell membrane

Structure: 3D network of branching tubes/channels and pockets with ribosomes=rough ER

Without ribosomes=smooth ER

Function: Transports materials made in the cell throughout (fats and proteins)

Ribosome

Location:  Attached to ER or free-floating in cytoplasm

Structure: Small, dark spheres

Function: Site of protein synthesis (making)

Proteins help the cell to function properly and carry out activities 

Centriole

Location: Only in animal cells

In cytoplasm

Structure: Small cylinders (barrel-like shape, stacked straws)

Function: Involved in cell division

Provides attachment for spindle fibers

Chromatin

Location: Inside the nucleus

Structure: Stands of DNA and proteins

Function: Involved with reproduction and the inheritance of traits

Cell wall

Location: Surrounds the cell membrane of plant cells only

Structure: Tough, rigid structure with pores

Made of cellulose

Function: Provides support and protection

Chloroplast

Location: In cytoplasm of plant cells only

Structure: Inner and outer membrane surround tiny sacs called thylakoids

Function: Contain green pigment called chlorophyll (used to capture suns energy during photosynthesis) water, carbon dioxide and sunlight are combined to produce food for the plant and to release oxygen