Biology Cells, Exchange and Transport: Organelles

Nucleus

Endoplasmic Recticulum (Smooth and Rough)

Golgi Apparatus

Mitochondria

Chloroplasts

Lysosomes

Ribosomes

Centrioles

Structure

* darkened patches called chromatin

* surrounded by nuclear envelope

* made of two membranes, with fluid in between them

* nuclear pores go through the nuclear envelope

* inside nucleus, there is a dense spherical structure called the nucleolus.

Function

* holds the cells genetic material, chromatin consits of DNA and proteins

* has the instruction for making proteins, which regulate cells' activities

* during cell division, chromatin turns into visible chromosomes

* nucleolus makes RNA and ribosomes.

Structure

* stack of membrane bound, flattened sacs

Function

* receives proteins from ER and modifies them e.g adding sugar

* packages modified proteins into vesicles

Structure

* flattened, membrane bound sacs called cisternae

* continuous with outer membrane

* Rough ER is studded with ribosomes

* Smooth ER does not have ribosomes

Function

* Rough ER transports proteins made on the attached ribosomes

*Smooth ER involved in making lipids

Structure

* spherical or sausage shaped

* two membranes separated by fluid filled space

* inner membrane highly folded to form cristae

* central part called the matrix

Function

* ATP (adenosine-triphosphate) is produced during respiration

* called the universal energy carrier

Structure

* only in plant cells and some protoctists

* two membranes separated by a fluid filled space

* continuous inner membrane with a network of thylakoids

* thylakoids are flattened membrane sacs

* stack of thylakoids called granum (plural grana)

* chlorophyll molecules present on thylakoid membranes

Function

*site of photosynthesis

Structure

* spherical sacs surrounded by a single membrane

Function

* contain powerful digestive enzymes

* role is to break down materials

* e.g. white blood cell lysosomes help to break down invading microorganisms.

Structure

* some are in cytoplasm

* some are bound to ER

* each one consists of two subunits

Function

* site of protein synthesis

* act as an assembly line where coded info (mRNA)is used to assemble proteins from amnio acids

Structure

* small tubes of protein fibres (microtubules)

* pair of them next to nucleus

Function

* take part in cell division

* for fibres called spindle which move chromosomes during cell division