biology- a level organelles

function of cell surface membrane

• made of lipids and proteins

• regulates substances in and out

• has receptor molecules

• thin barriers

5 key features of a cell surface membrane

• surround organelles

• may contain pores

• may be selectively permeable

• may be stacked or folded

• may be fluid

function of a mitochondria

• site of aerobic respiration

• produces ATP → common energy source in the cell

• found in large numbers in active cells → require lots of energy

structure of mitochondria

• usually oval shaped

• double membrane

• inner one folded to form cristae

• matrix → contain enzymes → for respiration

chloroplast

• small flattened structure

• in plant and algae cells

• double membrane

• folded inner membrane → thylakloid → stacked up in parts of the chloroplast →granum → linked with lamella

• photosynthesis happens in the granum and stroma

function of a nucleus

• surrounded by nuclear envelope → double membrane

• contains chromosomes called nucleolus

• pores allow substances to move between nucleus and cytoplasm

• DNA contains instructions to create protein

• controls cells activities

smooth endoplasmic reticulum

• no ribosomes

• similar to RER

• synthesises and processes lipids

rough endoplasmic reticulum

• ribosomes on surface

• system of membranes

• encloses fluid filled space

• folds and processes proteins made at ribosome

ribosomes

• small organelles that float free

• no membrane

• in cytoplasm or attached to RER

• made up of proteins or DNA

golgi body

• processes, packages new lipids and proteins

• makes lysosome

• group of fluid-filled membrane-bound, flattened sacs 

golgi vesicles

• seen at the edge of the sacs

• stores lipids and proteins

• small fluid filled sac in the cytoplasm

• surrounded by a membrane

• produced by the golgi body

lysosome

• contains digestive enzymes → lysozymes

• used to digest invading cells

• or break down worn out components of the cell

• round organelle surrounded by a membrane→ type of golgi vesicle

cell wall

• rigid structure

• surrounds cells in plants, algae, fungi

• function : supports cells, prevents them from changing shape

vacuole

• membrane-bound organelle

• surrounding membrane → tonoplast

• found in the cytoplasm, which contains cell sap

• function: maintains pressure inside the cell and keeps the cell rigid stopping it from wilting

centrioles