Cell structure Flashcards
What does prokaryotic mean
Pro-before
Karyote - nucleus
Contains no membrane bound organelle
What does eukaryotic mean
contains a nucleus and membrane bound organelle
What is the function of the nucleus
Holds/stores genetic information for polypeptides
Produces mRNA and tRNA
Transcription and DNA replication occurs
Structure of the nucleus
Consists of nuclear envelope and pores
Double membrane and pores
nucleoplasm
chromosomes/DNA
Nucleolus
What is the structure and function of the nuclear envelope
Double membrane and pores
function -> continuous with the RER, controls the entry and exit
passage of large molecules
Structure and function of the nucleoplasm
Granular jelly like substance similar to the cytoplasm, suspends other nuclear structures within it
What is it?
Cell surface membrane?
A phospholipid bilayer composed of proteins that surriund the cell and protect them from the environment
What is the structure surrounding the nucleus called?
The envelope
The envelope is a double membrane that contains nuclear pores.
What is the function of nuclear pores?
Enables molecules to enter and leave the nucleus
There are approximately 3000 nuclear pores in the envelope.
What is the site of ribosome production within the nucleus?
Nucleolus
What is the jelly-like material inside the nucleus called?
Nucleoplasm
What are the characteristics of the rough endoplasmic reticulum?
Flattened sacs enclosed by a membrane with ribosomes on the surface
RER folds and processes proteins made on the ribosomes.
What is the primary function of the smooth endoplasmic reticulum?
Produces and processes lipids
What is the structure of the Golgi apparatus?
Fluid filled, flattened & curved sacs with vesicles surrounding the edges
The Golgi apparatus processes and packages proteins and lipids and produces lysosomes.
What are the key features of mitochondria?
Oval shaped, double membrane with inner membrane folded into cristae
The matrix contains all the enzymes needed for respiration.
What role do centrioles play in a cell?
Involved in producing spindle fibres for cell division
What are ribosomes made of?
Two subunits
What do lysosomes contain?
Digestive enzymes
Lysosomes are vesicles bound by a single membrane.
What is the function of the cell wall in prokaryotic cells?
Rigid outer covering made of peptidoglycan
What is the purpose of the capsule in prokaryotic cells?
Protective slimy layer that helps retain moisture and adhere to surfaces
What is a plasmid?
Circular piece of DNA
What is the function of the flagellum in prokaryotic cells?
A tail-like structure that rotates to move the cell
What are pili?
Hair-like structures that attach to other bacterial cells
What are mesosomes?
Infoldings of the inner membrane containing enzymes required for respiration
