Aqa A level Biology - Topic 2 Cells

what is the structure of cell surface membrane

phospholipid bilayer. receptors for cell recognition and attachment

what is the function of the cell surface membrane

controls exhchange between the cell and its environment

what is the structure of the nucleus

contains chromosomes consisting of protein bound linear DNA and one or more nucleoli

what is the function of the nucleus

involved in protein synthesis- transcription of DNA code onto RNA copy

what is the structure of mitochondria

two membranes called inner and outer. inner folded to form cristae which surround the matrix

contains circular DNA and 70S ribosomes

what is the function of mitochondria

site of aerobic respiration using oxygen to make ATP

what is the structure of chloroplasts

double outer membrane with stroma inside

grana- parallel stacked membrane thylakoids

often contains starch grains

70S ribosomes and circular DNA

what is the function of chloroplast

site of photosynthesis

thylakoid contains chlorophyll to absorb light for photosynthesis

what is the structure of golgi apparatus/body

stack of dynamic flattened cisternae

what is the function of golgi apparatus

packages and transports proteins from the RER for secretion out the cell

modifies proteins

transports lipids

what is the structure of lysosomes

type of golgi vesicle

contains lysozymes

what is the function of lysosomes

breakdown unwanted organelles/structured/bacteria in phagocytosis

lysosomes fuse with membrane of digestive vacuoles

what is the structure of ribosomes

made of rRNA and protein.

80S ribosomes in eukaryotes

what is the function of ribosomes

synthesise proteins from amino acids

what is the difference between RER and SER

RER has ribosomes attached whereas SER does not

what is the function of RER

has ribosomes attached which attach to mRNA in protein synthesis

acts as a transport system

what is the function of SER

makes lipids and steroids

transports lipids

what is the structure of cell wall in plants and algae

cellulose microfibrils polysaccharide

outside the cell membrane

what is the structure of cell wall in fungi

made of chitin

what is the function of the cell wall

gives cell its shape

prevents bursting

fully permeable to water and solutes

what is the structure of vacuoles

small vesicles in animal cells

large and surrounded by a tonoplast in plant cells

what is the function of vacuoles

plant cell vacuoles function as storage sites

animal cell vacuoles may be formed during phagocytosis

what is a tissue

a group of similar cells carrying out the same function

what is an organ

a group of several tissues that perform a particular function for the whole organism

what is an organ system

several organs working together

what do all prokaryotic cells contain

• no membrane bound organelles

• 70S ribosomes

• no nucleus

• a murein cell wall

what do only some prokaryotic cells contain

• plasmids

• capsule

• flagella

what do all viruses contain

• genetic material

• capsid

• attachment proteins

are viruses living or non living

non living

what’s the function of viruses genetic material

codes for viral protein