Eukaryotic Cell Structure- Alevel Biology

Nucleus

• center of cell

• includes nucleus envelope, nucleolus, and nuclear pores

• Has a double membrane

• houses DNA and controls cell activities.

• Controls protein synthesis, produces mRNA and tRNA

• Manufactures rRNA and ribosomes

nucleolus

• Centre organelle inside nucleus

• Assembles ribosomes

• Synthesizes RNA

Nucleoplasm

• A jelly like substance that makes up the bulk of the nucleus.

Function of the nucleus

• Store the Dna

• Control the cell activities

• Manufacture rRNA and ribosomes

• Control centre for protein synthesis

• Production of mRNA and tRNA

Nuclear envelope

• double membrane

• has pores

• continuation onto ER

• Surrounds the nucleus

• provide entry and exit of proteins and RNA through pores

Nuclear pores

Allow large molecules to pass, such as mRNA out the nucleus.

Ribosome

• Made of 2 sub units

• Made by the nucleulus

• membrane bound to the RER or free

• Site for protein translation.

• Made out of rRNA and protein

Function of ribosomes

Protein translation

Cell membrane

• "selective permeability"

• multi layer

• surrounds cytoplasm - lipids, proteins, carbs

• Chemical reactions happen here

Cell wall

• provides structure and support to cells under osmotic pressure

• Plant cell wall made if Cellulose

• Fungi cell wall made of Chetin

Mitochondria structure

• Has a double membrane

• Has Cristae, matrix, inner and outer membrane.

Mitochondria function

Supply the cell with energy from aerobic respiration.

Chloroplast

• Has a double membrane

• stroma: inside space

• thylakoid system: connect thylakoid membrane in grana, convert light energy into chemical energy

• chlorophyll: helps process of photosynthesis

Rough Endoplasmic Reticulum

• photosynthesis

• produce proteins and lipids required for production of chloroplast membrane

Cytoskeleton - general role

• made up of microtubules,

• support to cell and maintain its internal structure

• Provides tracks by which vesicles are carried around inside the cell

Centrisome

• Made up of 2 centrioles

• Which allow the mitotic spindle to form for mitosis and cytokenisis

Rough Endoplasmic Reticulum

• network of membranes that contains ribosomes

• produce proteins for cell

• Has membrane bound ribosomes to translate proteins from mRNA

Smooth Endoplasmic Reticulum

• contains tubular membranes

• does not have ribosomes on the surface

• plays role in synthesis of carbohydrates and lipids

Golgi apparatus

• made up of series of stacked cisternae

• located in cytoplasm next to endoplasmic reticulum

• transportation, modification, packaging of lipids and proteins into vesicles to deliver diff. destination in cell

Lysosome

• membrane bound organelle contains digestive enzymes and lysozyme.

• breaks down excess cell parts and worn out cell parts

Vacuoles

• space within cell

• empty of cytoplasm

• lined with membrane, filled with fluid

The mitochondria matrix

Contains protein, lipids ribosomes and Dna- that allows the

Cristae

Extensions of the inner membrane which provides a large surface area for enzymes and proteins to attach during respiration

Tonoplast

The membrane that surrounds th vacuole

Stroma

The matrix in a cholorplast

Granum/Grana

A series of stacked thylakoids