Cell Structure and Function

Cell Structure and Function

Cell: Basic unit structure and function in

living things.

2 Types of Cells

PROKARYOTES

Lack nucleus

Lack organelles

Only unicellular

EUKARYOTES

Have nucleus

Have membrane bound

organelles

Uni-/Multicellular

Only Example -

bacteria

Examples -

animal, plant, fungi, protists

Cells differ in size, shape and function. ALL cells have these components – BOTH prokaryotic and eukaryotic cells:

• Cell Membrane

• DNA

• Cytoplasm

• Ribosomes

Cell Structure and Functions

Organelles are specialized structures

INSIDE the cell that have their own

functions. Organelles function together to

help the cell carry out all of life’s activities.

Remember: ONLY EUKARYOTIC

CELLS HAVE ORGANELLES!!!!

Cell Structure and Function

Structure Function

• Cell or Plasma Membrane • Serves as barrier between

cell & its environment

• Controls the movement of

materials in/out of cell to

maintain homeostasis

Cell Structure and Function

Structure Function

• Cell Wall • Thick, inflexible outer layer

surrounding the cell

membrane that provides

support and protection

• Made of cellulose

• NOT found in animal cells

Cell Structure and Function

Structure Function

• Cytoplasm • Semi-fluid matrix (cytosol)

containing organelles

• Provides support and

protection for organelles

Cell Structure and Function

Structure Function

• Chromosomes • Contain DNA.

• Found in the nucleus of

eukaryotic cells and in the

nucleoid region of

prokaryotic cells.

Cell Structure and Function

Structure Function

• Nucleus • Contains the

chromosomes (DNA)

• Controls cell activities

such as protein synthesis

Cell Structure and Function

Structure Function

• Nucleolus • Non-membrane structure

located in nucleus

• Where ribosomes are

produced

Cell Structure and Function

Structure Function

• Ribosomes • Non-membrane structures

that are attached to the

Rough ER or free in the

cytoplasm

• Produce proteins

Cell Structure and Function

Structure Function

• Endoplasmic reticulum (ER) • System of channels and sacs that is

connected to the nucleus and

extends through cytoplasm

• Aids in protein synthesis and

transport of materials

• Two types of ER’s: Smooth & Rough

• Rough ER – has ribosomes on

surface, involved in protein synthesis

and transport

• Smooth ER – no ribosomes on

surface; involved in lipid synthesis

Cell Structure and Function

Structure Function

• Golgi Apparatus • Flattened sacs that modify

proteins, package them

inside transport vesicles,

and send them to their

destination

Cell Structure and Function

Structure Function

• Vacuole • Saclike structures that

store amino acids, sugars,

metabolic and toxic waste

• Also called vesicles

• Plant cells have a large

central vacuole that stores

water and other molecules

Cell Structure and Function

Structure Function

• Lysosomes • Vesicle containing digestive

enzymes that break down

and recycle organic

compounds

• Destroys cell parts, the

entire cell or pathogens

• RARELY found in plant

cells

Cell Structure and Function

Structure Function

• Chloroplast • Plastid only found in plants and

algae

• Site of photosynthesis -

transforming sunlight energy

directly into food

• Contains green pigment called

chlorophyll

• Has own DNA & can self

replicate

• NOT found in animal or fungi

cells

Cell Structure and Function

Structure Function

• Mitochondria • Site of aerobic cellular

respiration - Uses energy from

food to make ATP (adenosine

triphosphate) that the cell can

use to grow, develop and move

• Has own DNA and can self

replicate

• Very active cells have more

mitochondria

Cell Structure and Function

Structure Function

• Cilia • Short, more numerous hair

like structures made of

bundles of microtubules

located outside cell

• Assist in cell movement or

propelling foreign

substances around the cell

Cell Structure and Function

Structure Function

• Flagella • Long whip like tail of

microtubule bundles

located outside cell

• Used for cell movement;

usually 1-3 in number