Organelles - Structure and Function

Structure:

- Largest organlle in cell
- Surrounded by Nuclear Envelope
- Nuclear Envelope made up of two layers with fluid filled space inbetween
- Nuclear envelope has nuclear pores - large enough to allow relatively large molecules through

- Nucleolus located inside nucleus 

Function:

-Contains genetic material
-Chromatin - consists of DNA & Proteins
-Has the instructions for making proteins
-Nucleolus makes RNA & Ribosomes 

Structure:

- Consists of cisternae

(NOTE- Cisternae are flattened membrane bound sacs)

- Rough Endoplasmic Reticulum is studded with ribosomes
- Smooth Endoplasmic Reticulum does not have any

Function:

- Rough Endoplasmic Reticulum Transports proteins (proteins that were made attached ribosomes

- Smooth Endoplasmic Reticulum - makes lipids 

- Proteins secreted from cell or placed on cell surface membrane 

Structure:

- Stack of flattened membrane bound sacs

Function:

- Receives proteins from Rough Endoplasmic Reticulum 

- Modifies & Packages proteins into vesicles

- Can then be transported to cell surface membrane to be secreted from cell

(NOTE: When a protein is modified by the Golgi Apparatus, sugar molecules may be added)

Structure:

- Two membrane layers - fluid filled space in between

- Inner membrane is highly folded - known as a cristae

- Central part of Mitochondria - Matrix

- Spherical / Sausage shaped 

Function:

- Site where ATP is produced

- Cell's activities are driven by ATP 

- ATP produced during respiration

Structure:

- Only found in plant cells

- 2 membranes separated by fluid filled space

- inner network is compact - flattened membrane bound sacs - THYLAKOIDS 

- Stack of Thylakoids  - Granum 

-Chlorophyll molecules present on the thylakoid membranes 

Function:

- Site of photosynthesis

- Light energy used to drive the reactions of photosynthesis

- Carbohydrates made from CO2 & Water 

Structure:

- Contain powerful digestive enzymes

- Spherical sacs surrounded by single membrane

Function:

- Break down materials

- Example: White blood cells break down invading microorganisms 

Structure:

- 2 subunits each

- found in cytoplasm / bound to Endoplasmic reticulum 

Function:

- Site of protein synthesis (where proteins are made)

- Ribosomes are the assembly line - mRNA from the nucleus is used to assemble proteins from amino acids 

Structure:

- Not surrounded by membrane 

- Small tube of protein fibres - microtubles 

- Pair next to nucleus in animal cells

Function: 

- Take part in cell division 

- Forms fibres - Spindle Fibres

- Moves chromosomes in cell division