(WIP) ocr biology year 1: microscopy and cell structure

describe the nucleus’ structure

• Contains DNA

• Contained within a double membrane (nuclear envelope) which has nuclear pores to allow molecules to move in and out.

describe the nucleus’ function

• DNA replication and transcription

• Controls metabolic activities of the cell

describe the structure of the nucleolus

• Area within the nucleus

• Densely staining

• Composed of proteins and RNA 

describe the function of the nucleolus

• Produces ribosomes

describe the structure of the mitochondrion

• Has a double membrane

• Inner membrane is folded into cristae

• The fluid interior is called the matrix

• Contain mitochondrial DNA (mtDNA) 

describe the function of the mitochondrion

• Site of final stages of aerobic cell respiration (produces ATP)

• The membrane forming the cristae contains the enzymes used in respiration

describe the structure of the vesicles

• Membranous sacs with storage and transport roles

• Have a single membrane with fluid inside

describe the function of the vesicles

• Transport of materials within the cell

describe the structure of the lysosome

• Specialised vesicle containing hydrolytic enzymes

• Densely stained in electron micrograph

describe the function of the lysosome

• Breaking down waste material in cells including old/damaged organelles and pathogens ingested by phagocytic cells

describe the structure of the rough endoplasmic reticulum

• Made up of flattened membranous sacs called cisternae

• Has ribosomes bound to the surface 

describe the function of the rough endoplasmic reticulum

• Synthesise proteins usually for secretion from the cells (in vesicles which travel via the Golgi apparatus)

describe the structure of the smooth endoplasmic reticulum

• Made up of flattened membranous sacs called cisternae

• NO ribosomes bound to the surface

describe the function of the smooth endoplasmic reticulum

• Lipid and carbohydrate synthesis and storage

describe the structure of the free ribosomes

• Not surrounded by a membrane

• Made of RNA

describe the function of the free ribosomes

• Site of protein synthesis

describe the structure of the Golgi apparatus

• Similar in structure to SER

• Made up of flattened membranous sacs (cisternae) from which vesicles can bud off

describe the function of the Golgi apparatus

• Role in modifying proteins made in the RER and packaging them into vesicles