organisation of organisms

• what is a cell 


  the smallest unit of living matter
• what are the two types of cells

  eukaryotic, prokaryotic
• the nucleus contains genetic material and controls the activities of the cell
• the cytoplasm is the site of many chemical reactions
• the cytoplasm is a gel-like substance which supports internal cell structures
• the cell membrane is a selectively permeable barrier that controls the movement of substances in and out of the cell
• the ribosomes are the site of protein synthesis in the cell
• the mitochondria is the site of aerobic respiration and is where energy is released to fuel cellular processes
• the cell wall is made of cellulose in plants
• the cell wall is made of chitin in fungi
• the cell wall is made of peptidoglycan in bacteria
• the cell wall supports the cell and defines it shape
• the cell wall protects a plant cell from bursting due to turgor pressure
• the vacuole is a fluid filled sac that stores water and nutrients in plants
• the vacuole supports the plant and gives it its shape by applying turgor pressure on the cell wall
• the nucleus controls all activities within the cell, including protein synthesis
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• levels of organisation 


  cell, tissue, organ, organ system
• what is a tissue

  a group of similar cells working to perform the same function
• what is the function of a RBC

  transports oxygen around the body for respiration
• RBCs have a biconcave shape to increase surface area to be able to carry more oxygen
• RBCs have no nucleus to make space for hemoglobin
• RBCs have hemoglobin to bind to oxygen
• RBCs are 7mm in diameter which is the exact diameter of a capillary
• new cells are produced by the division of existing cells
• what is the function of egg and sperm

  carry genetic material for reproduction
• sperm cells have a tail to swim
• sperm cells have a haploid nucleus
• ciliated cells beat to sweep pathogens and bacteria back up the throat
• goblet cells make mucus to trap dust and bacteria
• what is the function of palisade mesophyll cells 


  absorb light energy from the sun for photosynthesis and where photosynthesis takes place
• palisade mesophyll cells have many chloroplasts to absorb lots of light for photosynthesis
• palisade mesophyll cells have a large vacuole to push chloroplasts to the edge
• palisade mesophyll cells are fou9nd at the top of the leaf to absorb as much sunlight as possible
• palisade mesophyll cells are arranged vertically to maximise absorption of sunlight
• root hair cells absorb water and mineral ions from the soil

  A) cell membrane
• root hair cells have a long thin projection to increase surface area
• root hair cells have thin walls to decrease diffusion distance
• root hair cells have many mitochondria to provide energy for active transport
• root hair cells have concentrated cell sap to increase rate of osmosis