cell structure Flashcards
what are the organelles inside an animal cell?
nucleus, nuclear pores, nucleolus, ribosomes, plasma membrane, smooth ER, rough ER, mitochondria, Golgi apparatus
what are the organelles in a plant cell
nucleus, nuclear pores, nucleolus, rough ER, smooth ER, mitochondria, ribosomes, cellulose cell wall , plasma membrane, vacuole, chloroplast, Golgi
what are the components of the nucleus and what do they do
nuclear envelope = A double membrane made of phosphates.
nuclear pores = gaps in the membrane allowing molecules to pass such as MRNA
nucleoplasm = jelly like substance taking up most of the nucleus
nucleolus= where RNA and ribosomes are synthesised
chromosomes = protein bound linear DNA
what does the nucleus do?
site of DNA replication and transcription (making MRNA resulting in protein synthesis). Retain genetical information. Manufactures RRNA and ribosomes
what does mitochondria do and what are its components
mitochondria produces APT ( adenosine triphosphate) via respiration
- site of aerobic respiration
- double membrane
- contains cristate (extensions of the inner membrane providing a large surface area)
- contains a matrix including ribosomes, protines, lipids and DNA
what are the properties of the chloroplast
- surrounded by a double membrane
- contains stacks of thylakoids called grana they contain chlorophyll. granal membranes have large surface areas.
- DNA and ribosomes are present for easy manufacturing of proteins
what are the endoplasmic reticulum and what are the properties of the 2.
It is sheet like membranes throughout the cell continuous from the nucleus and has tubules and flattened sacs (cisternae).
- rough ER = contains ribosomes for a large surface area for protein synthesis and lipids also is a pathway for transport of molecules throughout the cell.
- smooth ER = Lacks ribosomes. Synthesizes, stores lipids and carbohydrates
what does the Golgi apparatus do and its propites
It makes/transports glycoproteins
- compromised ser of flattened sacs called cisternae
- proteins and lipids are modified and transported in vesicles
- proteins are modified by addition of carbohydrates and turn into glycoproteins
- vesicles located in the cytoplasm
- lysosomes are produced in the Golgi ( special type of Golgi vesicle )
what do lysosomes do and there properties
functions Digest food molecules that enter the cell.
. Perform autophagy (destruction of improperly functioning organelles).
. Break down excess or worn-out cell parts.
. Destroy invading viruses and bacteria.
. hydrolyse phagocyted material
-produced via the golgi
-contain protease, lipase and lysozymes ( enzymes which hydrolyse the cell wall of some bacteria )
- they fuse with vessels
what are ribosomes made from and the properties
they are small cytoplasmic granules found in all cells made of protein and RRNA
- 80s ribosomes found in eukaryotic cells
-70s found in prokaryotic cells
- They are the site of protein synthesis
what is the cell wall made of in
plant and algae
fungi
bacteria
plant and algae = made of cellulose, cellulose microfibres embedded in a matrix. Provide mechanical strength and structure. water moves along via adhesion
fungi = made of chitin
bacteria made of peptidoglycan ( also called murein )
What are the propites of the vacuole
. Fluid bound sacs bound by a single membrane (the tonoplast)
. makes plants turgid
. Stores sugars plus amino acids
. may contain pigments the colour petals
What is the plasma membrane made up of
- A phospholipid bilayer
- cholesterol
- transmembrane proteins
- peripheral proteins
- glycoproteins
How is the phospholipid bilayer structured
they have a electrically charged hydrophilic head and a hydrophobic tale
this means the tales are facing towards each other
the bilayer is impermeable to some proteins and allows non polar substances to pass
what does cholesterol do and also glycoproteins in the plasma membrane
cholesterol - regulates fluidity
Glycoproteins - signalling and communication
What does the transmembrane and peripheral proteins do
transmembrane - transport
peripheral - anchoring (holding)
What is transcription
First stage of protein synthesis
what is a specialised cell
A cell that can differentiate to carry out a specific function
What are the Golgi vesicles and what do they do?
A small fluid sac in the cytoplasm surrounded by membrane and produced via the Golgi apparatus
stores lipids and proteins made by the Golgi and transports them out of the cell
