Cell structure

• Eukaryotes: organisms with a nucleus and membrane-bound organelles
• Eukaryotic cells: Cells that have a nucleus and membrane bound organelles
• Eukaryotic cells include animal and plant cells
• Prokaryotes: Single-celled organisms that lack a nucleus and membrane-bound organelles
• Prokaryotic cells: No nucleus, no membrane bound organelles
• Prokaryotic cells include bateria
• Eukaryotic cells:

  Between 5μm and 100μm

  Cell membrane - surrounded by cell wall in plants and fungi

  DNA in a nucleus - plasmids are found in a few simple eukaryotic organisms

  Cell Division: Mitosis
• Eukaryotic cells contain cytoplasm, mitochondria, chloroplasts in plants and ribosomes
• Prokaryotic cells:

  Between 0.2μm and 2.0μm

  Cell membrane - surrounded by cell wall

  DNA is a single molecule, found free in the cytoplasm

  Cell Divison: Binary Fission
• Prokaryotic cells include cytoplasm, ribosomes, no mitochondria or chloroplasts
• Cell Membrane: controls what goes in and out of the cell, controls what goes on inside the cell
• Cell wall: A rigid structure that surrounds the cell and provides support and protection.
• Cytoplasm: A gel-like substance that fills the space between the cell membrane and the nucleus.
• Mitochondria: Site of aerobic respiration, where most of the energy for cellular respiration is produced
• Chloroplasts: Site of photosynthesis, where photosynthesis occurs.
• Ribosomes: Site of protein synthesis in the cell.
• Nucleus: contains genetic material and controls cell activities.
• Plasmid: A small circular DNA molecule that is found in bacteria.
• Animal cells: Nucleus, cytoplasm, cell membrane, mitochondria, ribosomes
• Plant cells: Nucleus, cell wall, chloroplasts, vacuole, cell membrane
• Vacuole: A large, spherical structure that contains cell sap and is found in plant cells.
• Cytoplasm: The jelly-like substance inside the cell where most chemical reactions take place.
• Cell membrane: The outer boundary of the cell which separates it from its surroundings.
• Sperm: Tail (enables sperm to swim)

  Midpiece with mitochondria (releases energy)

  Haploid nucleus (contains genetic material)

  Acrosome (contains enzymes to penetrate egg)
• Nerve cell: long, thin, and branched, and has a nucleus.

  Dendrite, Nucleus, Cytoplasm, Cell membrane, Axon, Nerve ending
• Dendrite: A branch of a neuron that receives information from other neurons.
• Axon: The long, thin fibers that carry nerve impulses away from the cell body.
• Neurone: A specialized type of animal cell found in the nervous system that is responsible for transmitting electrical signals throughout the body.
• Mitochondrion: An organelle within eukaryotic cells that generates most of the chemical energy needed to power the cell's metabolism through aerobic respiration.
• Muscle cells: long, thin, and cylindrical, with lots of mitochondria
• Root hair cell: Specialised cell that has a large surface area for absorbing water and minerals
• Xylem cell: A type of plant cell that transports water and mineral ions from the roots to the leaves.
• Phloem cell: A type of plant cell that transports food substances from the leaves to the rest of the plant
• Animals and plants produced by sexual reproduction begin life as a single cell - a fertilised egg or zygote
• This cell must divide to produce a multicellular organism. It must also differentiate so that its cells develop features that enable them to fulfil specific roles
• Cells in circulatory system: Specialise to transport substances, defend the body and regulate temperature
• Cells in excretory system: Specialise to remove waste products and unwanted substances and regulate the water contents of the body
• Cells in the muscular system: Specialise to bring about movement
• Cells in the nervous system: Specialises to respond to external and internal stimuli and conditions, carry messages for the body work as a coordinated whole
• Cells in respiratory system: Specialises in delivering oxygen for respiration and removes waste