Chapter 2 - Basic Components of Living Systems Flashcards
Function of the nucleus
- contains genetic information as DNA stored as chromatin
- DNA controls protein synthesis, the cells metabolic activity, growth and reproduction
structure of the nucleus
- contained by nuclear envelope (double membrane) to protect from damage from cytoplasm
- nuclear pores control entry and exit of molecules from nucleus eg. mRNA
function of nucleolus
- produces ribosomes from proteins and rRNA
structure of nucleolus
- made of proteins and RNA (which is used to produce rRNA)
- in nucleus, not surrounded by a membrane
function of mitochondria
- site of cellular aerobic respiration and ATP production
structure of mitochondria
- double membrane
- inner membrane folds: cristae has high surface area
- matrix has enzymes for aerobic respiration
- circular DNA
function and structure of vesicles
- membranous sacs, single membrane with fluid inside
- used to transport materials inside the cell
function and structure of lysosomes
- specialised vesicles (single membrane)
- contain hydrolysing enzymes that digest organelles, cells and pathogens
structure and function of centrioles
- formation of spindle fibres
- crucial in spatial awareness of cell
- part of the cytoskeleton, made of microtubules
where are centrioles found
animal cells and some plant (except flowering plants) absent from most fungi
structure and function of cilia
- mobile/ stationary with microtubules arranged in 9+2 formation
- stationary: sensory function eg. in nose
- mobile: beat rhythmically to create a current
structure and function of flagella
- enables cells to be motile
- sometimes a sensory organelle used to detect environmental changes
structure and function of RER
- synthesis and transport of proteins
- a series of membranes continuous with nuclear envelope
enclosing flattened sacs: called cisternae - Ribosomes on surface
function and structure of smooth ER
- synthesis, transport and storage of lipids, carbohydrates and steroid hormones
- series of membranes not continuous with nuclear membrane, but with RER
- cisternae
strucure and function of ribosomes
- made of RNA molecules from nucleolus
- site of protein synthesis
- can be in cytoplasm or on RER
- also in mitochondria and chloroplasts
structure and function of Golgi apparatus
- stack of membrane-bound flattened sacs (cisternae)
- modify proteins + lipids (e.g. add sugar to make glycoproteins)
- and package into vesicles
different materials of cell wall
plant: cellulose
prokaryote: peptidoglycan
fungi: chitin
function of cell wall
- plants: provide shape, contents presses against it creating rigidity (turgor pressure), tensile strength
- prokaryotes: maintain shape
structure and function of permenant vacuole
- surrounded by single membrane tonoplast
- maintains turgor pressure to maintain rigid framework
- contains nutrients and metabolites
function of chloroplasts
chlorophyll in grana, where light dependent reactions occur during photosynthesis
structure of chloroplasts
- stacks of double membranes containing photosynthetic pigments
- stacks: grana, membranes: thylakoids
- fluid inside: stroma