Biology 1: Cell Biology Knowledge Organiser PDF

Biology 1: Cell Biology Section 1: Cell Structure Eukaryotic Prokaryotic 11 12 Animal Plant Bacterial Cell Structure Function...

Biology 1: Cell Biology Section 1: Cell Structure Eukaryotic Prokaryotic 11 12 Animal Plant Bacterial Cell Structure Function Cells Cells Cells Contains genetic information that controls the 1 Nucleus Y Y functions of the cell. 2 Cell membrane Controls what enters and leaves the cell. Y Y Y Where many cell activities and chemical 3 Cytoplasm Y Y Y reactions within the cell occur. 4 Mitochondria Provides energy from aerobic respiration. Y Y 5 Ribosome Synthesises (makes) proteins. Y Y Y 6 Chloroplast Where photosynthesis occurs. Y 7 Permanent Used to store water and other chemicals as cell Y vacuole sap. Strengthens and supports the cell. (Made of 8 Cell wall Y Y cellulose in plants.) 9 DNA loop A loop of DNA, not enclosed within a nucleus. Y A small circle of DNA, may contain genes 10 Plasmid Y associated with antibiotic resistance. Section 2: Specialised Cells Specialised Cell How structure relates to function Section 3: Microscopy Acrosome contains enzyme to break into egg; tail to swim; many The degree by which an object is enlarged. 13 Sperm cell 22 Magnification Magnification = size of image__ mitochondria to provide energy to swim. size of real object 14 Nerve cell Long to transmit electrical impulses over a distance. 23 Resolution The ability of a microscope to distinguish detail. Contain protein fibres that can contract when energy is available, making 15 Muscle cell 24 Light Basic microscope with a maximum magnification of 1500x. the cells shorter. microscope Low resolution. Long extension to increase surface area for water and mineral uptake; thin 16 Root hair cell Microscope with a much higher magnification (up to 500 cell wall. 25 Electron 000x) and resolving power than a light microscope. This 17 Xylem cell Waterproofed cell wall; cells are hollow to allow water to move through. microscope means that it can be used to study cells in much finer detail. Some cells have lots of mitochondria for active transport; some cells have 18 Phloem cell very little cytoplasm for sugars to move through easily. Section 4: Orders of Magnitude Unit Prefix Size in metres Standard Form 26 Centimetre 0.01m 10-2m (cm) 27 Millimetre 0.001m 10-3m (mm) 28 Micrometre 10-6m 0.000001m 21 – Root hair (μm) 19 – Sperm 20 – Nerve 29 Nanometre 10-9m cell cell cell 0.000000001m (nm)  Section 5: Mitosis and the Cell Cycle Section 7: Transport Across Membranes Number of sub-cellular structures Cell Growth, Definition 31 (e.g. ribosomes and mitochondria) Structure Uses increase DNA replicates. increase. Spreading out of the particles (gas/ in sub- Oxygen and carbon dioxide in gas Chromoso solution) resulting in a net cellular 32 Number of chromosomes double. 41 exchange (leaves and alveoli). me number movement from an area of higher structure doubles Diffusion Urea from cells into the blood plasma for One set of chromosomes is pulled to concentration to an area of lower s 33 excretion in the kidney. concentration. Mitosis each end of the cell. (cell More The diffusion of water from a dilute growth 34 The nucleus divides. 42 solution to a concentrated solution division) Osmosis through a partially permeable Movement of water into and out of cells. Cytoplasm and cell membranes membrane. 30 – Cell cycle 35 divide to form two identical cells Absorption of mineral ions (low The movement of substances from a concentration) from soil into plant roots. more dilute solution to a more 43 Active Absorption of sugar molecules from concentrated solution (against a Transport lower concentrations in the gut into the concentration gradient). Requires Section 6: Stem Cells blood which has a higher sugar Section 8:energy Factorsfrom respiration. Affecting Diffusion concentration. Stem Cell Properties Uses Factor Explanation Therapeutic cloning – embryonic stem cells 44 Difference in concentrations The greater the difference in concentrations, the faster the 36 Embryonic stem (concentration gradient) rate of diffusion. Can divide into most types of cell. produced with same cell Particles move more quickly at higher temperatures, so rate genes as patient. No 45 Temperature rejection. of diffusion increases. Can divide into a limited number of The greater the surface area the quicker the rate of 46 Surface area of membrane 37 Adult stem cell cells e.g. bone marrow stem cells can diffusion. form various blood cells. Section 9: Adaptations of Exchange Surfaces Clone rare species to Found in plants. Can differentiate (divide) prevent extinction. 47 Large surface area 38 Meristem 48 Thin membrane to provide a short diffusion path into any type of plant cell. Crops with special features can be clones 49 Ventilation (in animals for gas exchange – maintains a concentration gradient) Pros and Cons of Using Stem Cells 50 Efficient blood supply (in animals – maintains a concentration gradient) 39 Pros Treatment of diseases such as diabetes, dementia and paralysis. Ethical and religious objections. Can transfer viruses held 40 Cons within cells.