2.4 eukaryotic cell structure Flashcards
Mitochondria structure and function
S: double membrane. Inner membrane is folded to form cristae. Inside the matrix is enzymes responsible for respiration
F: Site of aerobic respiration (ATP production)
Vesicles function
transport material around the cell bound by a phospholipid bilayer
Cytoskeloton function and structure
s: made up of
- microfilaments: contractile protein fibres made of actin and bring abour contraction during cytokenieses
- microtubles: formed from cylindrecal protein tublin globular proteins scaffold structures, “tracks” for vesivles and organelles (spindle fibres are composed of microtubles, spindle fibres used in the segregation of chromatids)
-intermediate fibres: mechanical strength
F: provides structure and intracellular support
To include providing mechanical strength to cells,
aiding transport within cells and enabling cell
movement.
Cytoplasm function/def
site of chemical reactions. composed of cytosol
Lysosome function/def
specialised membrane-bound vesicles found in the cytoplasm that contain a hydrolytic (digestive) enzyme called lysozyme.
(SER) Smooth endoplasmic reticulum
A membrane-bound organelle involved in lipid
synthesis.
Rough endoplasmic reticulum (RER)
A membrane-bound organelle that is involved in the
synthesis and packaging of proteins.
Ribosomes def/function
Organelles found either free in the cytoplasm or membrane bound that are
involved in the synthesis of proteins. (some not membrane bound)
Nucleus def/function
An organelle found in eukaryotic cells that stores the genetic information of the cell
as chromosomes and is surrounded by a membrane called the nuclear envelope.
Nucleolus def/function
Nucleolus: A structure found inside the nucleus that contains proteins and RNA
and is involved in synthesizing new ribosomes.
Centrioles function
Structures found in the cytoplasm made of microtubules that produce the spindle fibres during mitosis. to organise the position of organelles. two centrioles form the centrosome
Golgi apparatus function
An organelle found in eukaryotic cells that is involved in the modification
and packaging of proteins.
Nuclear envelope
Nuclear envelope: A double membrane that surrounds the nucleus.
Plasma membrane
A semipermeable lipid bilayer studded with proteins that surrounds the
cell and many organelles.
Protein production overview steps 1-5
- proteins are synthesised on the ribosomes bound to the ER
- then passed into its cisternae and packaged into transport vesicles
- vesicles transport the protein to the Golgi apparatus via the cytoskeleton
4.fuses to the golgi where the proteins are modified, trimmed and then leave in vesicle to be excreted or used internally - secretory vesicle carry proteinsd that are to be released from the cell. vesicles fuse with the cell surface membrane releasing their contents by exocytosis.
some vesicles form lysosomes these contain enzymes for use in the cells
catabolic vs anabolic reactions
Catabolic reactions break down complex molecules into simpler ones, releasing energy, while anabolic reactions build complex molecules from simpler ones, requiring energy
explain why cells need to be compartmentalised and give three exapmles.
anabolic and catabolic reactions require differnt conditions. the reactions are incompatable eg. damage due to hydrolytic enzymes. nucleus, lysome,mitochondria
outline the differneces in structurea nd function between smooth and rough ER
rough has ribsomes attached and smooth er does not have ribosomes ataached rough er sythesis and modifies protein whereas smooth er is responsible fo rlipid synthesis.
suggest how dna is condensed/packed
coiled around histones wich are further coiled to form chromatin
