What is the structure of a mitochondrion (3)?
- rod shape/spherical
- 2 layers of membrane: smooth outer membrane, folded inner membrane
- contains respiratory enzymes
What are the functions of mitochondria (2)?
- site that generates energy through glucose oxidation
- energy in the form of ATP molecules
What are the structures of the centriole? (3)
- small, cylindrical, exists in pair
- made up of complex arrangement of microtubules
- does not exist in plant cells
What is the function of the centriole? (1)
- forms spindle fibre during cell division in animal cells
What are the structures of golgi apparatus? (2)
- stack of parallel flattened sacs coated by a single cell membrane
- new membrane added at one end and vesicles bud off from the other end
What are the functions of golgi apparatus? (Pn Rozanah’s 4 keywords)
- processing, modifying, packing and transporting chemicals (protein, carbohydrates & glycoprotein)
What is the structure of plasma membrane? (4)
- outer membrane that surrounds the entire cell
- made up of proteins and phospholipids
- thin and elastic film
- partially permeable
What are the functions of the plasma membrane? (3)
- separates content of cell from the external environment
- controls movement of substances in and out of the cell
- allows exchange of nutrients, respiratory gases and waste materials
What are the structures of the lysosome? (2)
- small, spherical sac enclosed in a single membrane
- contains hydrolytic enzymes
What are the functions of lysosome? (2)
- hydrolyses complex organic molecules (protein, lipid, nucleic acid)
- breaks down bacteria and components of damaged cells
What are the structures of the nucleus? (3)
- largest component in the cell
- spherical, compressed & enclosed in a nuclear membrane with many pores
- contains chromosomes, nucleolus and nucleoplasm
What are the functions of the nucleus (2)
- controls all cell activities
- has chromosomes that contain DNA which determines the cell characteristics and metabolic function
What are the structures of the ribosome? (3)
- small, compact & spherical granules
- consists of protein and RNA
- present on the surface of the rough ER / exists freely in the cytoplasm
What are the functions of ribosome? (1)
- site of protein synthesis
What are the structures of endoplasmic reticulum? (3)
- consists of a system of interconnected folded flattened sacs
- ER membrane is continuous with the nuclear membrane
- 2 types: - rough ER (has ribosomes attached to it)
- smooth ER (does not have ribosomes)
What are the functions of ER? (2)
- transport system within the cell
- provides wide surface for enzyme attachment & biochemical reactions
What are the functions of rough ER? (1)
- transports proteins synthesised by ribosomes
What are the functions of smooth ER? (2)
- synthesises and transports glycerol & lipids, carries out the detoxification of drugs & metabolic by-products
What are the structures of the vacuole? (5)
- liquid-filled sac (cell sap)
- surrounded by the tonoplast membrane
- young plants cells have many small vacuoles, mature plant cells have a large vacuole
- vacuole in animal cells is small
- cell sap contains water, organic acids, sugars, amino acids, mineral salts, oxygen, carbon dioxide & metabolic by-products
What are the functions of the vacuole? (2)
- water absorbed into the vacuole of plant cells & the cells become turgid
- unicellular organisms: vacuole contracts during osmoregulation, osmosis and excretion
What are the structures of the chloroplast? (3)
- oval shaped
- consists 2 layers of membrane
- contains chlorophyll pigments in the grana
What is the function of the chloroplast? (1)
- absorbs sunlight and converts it to chemical energy during photosynthesis
What are the structures of the cytoplasm? (2)
- jelly-like medium that contains components of the suspended cells
- contains organic compounds (protein, lipid, carbohydrate) & inorganic compunds (K+ ions)
What are the functions of the cytoplasm? (1)
- acts as a medium for biochemical reactions in cells
