Eukaryotic cells 1 - Common Cellular Structures Flashcards
What is a eukarotic cell
any cell or organism that possesses a clearly defined nucleus
what is the functions of membranes in eukaroytic cells
They localise enzymes in reaction pathways `
Describe the nucleus in Euarkotic cells
The largest orangelle in the cell
Spherical in shape
Surronunded by a double nuclear membrane containing holes or pores known as a nuclear envelope
Why does the nucleus have pores
Chemicals can pass in and out of the nucleus through these pores so that the nucleus can controll events in the cytoplasm
What is inside the nuclear envlope
nucleic acids and proteins
What are the nucleic acids in the nuclear envlope
DNA and RNA
What happens when the cell is not activley dividing
the DNA is bonded to the protein to form chromatin
What else is in the nucleus
a nucleous - extra dense area of almost pure DNA and protein
What is the nueclous involved in
production of ribsomes
What is the role of the mitochondria in eukaroytic cells
molecules are oxidised in the processes of cellular respiration producing ATP that can be used to drive other functions of the cell and indeed the organism
what surrounds the mitochondria
and outer and inner membrane
Why do mitochondria have the own gentic material
so that when a cell divides the mitochondria replicate themselves under the control of the nucleus
The mitochondrial DNA is what
part of the whole genome of the organis m
What is the structure of mitochondria
the inner membrane is folded to form cristae which give a very large surface area, surrounded by a fluid matrix. This structure is closely integrated with the events in cellualr respiration that take place in the mitchondria
in each cell there is a pair of what
centriloes near the nucleus
What is the centrole made up of
bundle of 9 tubles
What are the centrioles involved with
cell division when a cell divides the centrioles pull apart to produce a spindle of microtubles that are involved in the movement of the chromosomes
What is a cytoskelton
3D web like strucutre that fills the cytoplasm
What is the cytoskelton made up
microfilaments which are protein fibres and microbtubles- tiny protein tubes
Where are microtubles found
they are found singly and in bundle throughout the cytoplasm
What do microtubles consist of
globular protein tubulin
What is the function of the cytoskelton
gives the cytoplams a strucutre and keeps the organelles in palce
The cytoskleton is closely linked with the cell movements and transport within cells
Are vaculoes permanent
NO as they formed and lost as needed
What is the protplasm
the cytoplasm and nucleus combines
Whar does scanning EM show
Intact organelles allowing detailed measurremnts of the outer dimensions to be taken or it can take 4d images along fracture lines
