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Infection and response
Organisation
Cell biology
Biological molecules
Homeostasis and response
Responding to change (a2 only)
Energy transfers (a2 only)
The control of gene expression (a-level only)
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
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1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
Britain & the wider world: 1745 -1901
Inter-war germany
World war one
2n revolution and dictatorship: russia, 1917-1953
World war two & the holocaust
1l the quest for political stability: germany, 1871-1991
The cold war
2j america: a nation divided, c1845-1877
Medieval period: 1066 -1509
The fight for female suffrage
2m wars and welfare: britain in transition, 1906-1957
2d religious conflict and the church in england, c1529-c1570
Britain: 1509 -1745
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04/10/2023
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Science Cells Eukaryotes and Prokaryotes 8 Eukaryotic cell 5 Mm - 100 μm cell membrane - cytoplasm, sett mitochondria Pro Karyotic cell and ribosomes. • DNA in a nucleus mitosis. • 0.2 μm - 2.0μm cell membrane surrounded by cell wall in plants and fungi. chloroplasts (in plants), / outer layers of cell cell contents type of cell division. surrounded by cell wall Eukaryotic cells animal cell Prokaryotic cell - Bacterial cell. genetic material size Cytoplasm, ribasomes A- • DNA is a single molecule, free in the cytoplasm. also found in plasmid rings. binary fission + plant cell cell size Science - cells most animal and plant cells are 0.01 -0.10mm in size. cells are best measured using the micrometre, μm. Sub • cellular structures are best measured using the nanometre, nm. magnification = real size: 0.08min book = 100mm, 100 mm 0.05 mm. = 2000 Animal cell3 cytoplasm Nucleus Mitochondria Science cells Ribosomes O Cell membrane- It is mitochondrion nucleus ribosomes cytoplasm cell membrane. A jelly-like material that contains dissolved nutrients and Salts and structures called organelles. It is where many of the chemical reactions happen. Contains genetic material controls the cell's activities. It's structure is permeable to some substances, but not others. It therefore Controls the movement. of substances. in and out of the cell. Organelles that contain the and where including DNA, which in respiration Ting structures enzymes for respiration, released the most energy is where protein Syn thesis accurs. Most cells are specialised and are adopted for their function. Plant cells Chloroplasts Cell wall Science Cells Same Structures as Structures. . Chloroplasts •nucleus ribosomes. cell wall vacuole cell membrane is cytoplasm. animal cells, with some additional Organelles that contains the green pigment, Chlorophyll, which absorbs light energy for Photosynthesis....
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Contains the enzymes enzymes needed for photosynthesis.. Made from cellulose fibres and strengthens. the cell, and supports the plant. Permanent vacuole - filled with cell sap to help keep the cell turgid. Animal Specialised animal cells. complete Cell Specialisation. red blood cells. Science Sperm cells Egg Cell - - a specific purpose. Cilliated cells cells have components that allow them to carry oxygen around. the body. no Contain haemoglobin (carries oxygen). nucleus (more space for oxygen). biconcave (gives them. a larger surface are). join with egg cell to form an embryo. tail (moves them toward egg cell) many mitochondria (releases energy) has a to digest acro some releases enzymes the egg membrane. haploid contains genetic material. produced in large numbers. embryo. to form an contains col nutrients fo join with sperm cell. cytoplasm The haploid Cell membrane changes. So more sperm contains genetic material.. after fertilisation cells can enter. found in airways. Mave tiny hoirs called cilia, which beat in a mythm. These hairs move mucus. Animal Nerve cells muscle cells. Villi cell Specialisation.. - Science Cells - trasmit electrical signals in the nervous system. thin to Carry messages around the body quickly. branched connections at each end, to join other nerve to cells. fatty sheath (myelin) that surrounds them, increasing speed that mesages. Can travel. bundles to make up to contract and relax. found in able Cardiac pump Our around Smooth muscle cells make of muscle. contract and relax to body. thin sheets muscles. blood Skeletal muscle is joined to bones, Contracts to make bones move and joints bend. Structures about Che small one millimetre long in and large intestines. Millions of them pake out to absorb food and water into the blood. large surface area. thin walls one cell thick cells of the lining have ting hairs. Plant Cell Specialisation. root hair cells Palisade cells. Science Cells Phloem - found hold plants in absorb Outside surface of roots are covered in with root hair cells, hair cells. increase surface area. as place they grow. minerals from soil. water and the major of leaf (maximum) Pat Palisade cells. Site for photosynthesis. the top towards lot's of chloroplasts. are Xylem and phoem cells: xylem - transport water from roots to other parts of the plant. Cells die and the ends break down, allowing them to form long tubes to carry water upward for photosynethsis. Thick to support support the plant. walls near the xylem cells in the stem. Phloem cells are alive. They carry sugary water from the leaves to the rest of the plant. Cell division by mitosis. mitosis is when cells divide when; -an Cell cycle : cell begins to divide Science - Cells DNA replicates r Cell stops dividing/ resting period ↑ Cytoplasm seperates two cells formed Nuclear membrane breaks down. ✓ nucleus divides organism grows organism becomes damaged and needs to produce. new cells. Cell growth Mitosis →>>> 2 DNA synthesis ✓ further two cells called daughter cells. are produced during mitosis. Each identical to the parent cells. length of different stages of the cell cycle can enstimated & be using. length of time in phase= observed numbers of cello at that stage total number of cells obsened divide to form two identiral cells growth DNA checked. for errors x 606 al length of of сей адос time Science - cells Stem cells in a humans. Stem cells are cells that have not undergone differentiation. Adult stem cells can be found in the: brain, adult „Stem cells can differentiate into related cell types only... eyes, blood, heart, liver, bone marrow, Skin, muscle. Stem cells in plants. Cell division in plants occurs in regions called meristems. Meristem cells can^ differentiate to produce all types of plant cells at any time during the life of a plant. Diffusion Science -Cells particles in a liquid and gas move continuously. Because of this movement, particles will spread evenly throughout a liquid or a gas. If there is a situation where particles of a substance are. in a higher concentration, they will move from a region. where they are in a lower concentration. This is called diffusion. to Particles will move in both directions, but there will be from high to low concentration. a net movement Particles will end up evenly spread throughout the liquid or gas, but will continue to move. Examples include: lungs, leaps liver cells. Surface area to volume. Organisms must substances. Science Small Cells take in nutrients and ratio. organisms exchange. these essential and waste Substances between. themselves and the enviroment.. Chemical They do this over. their body surface. Simple can diffuse in and out of their bodies. Substances. their sett surface area does. not increase as fast as volume. the The size of their surface, or surface area, defines Cubsorb Substances. The size how quickly they can. of their volume defines. how much of these substances. they need. Gell of an organism - cobe. As the volume increases, surface area does not increase at the same rate. As multicellular organisms increase in size problema. Problem their volume increases remove waste insufficient surface area to meet their need. diffusion is not quick enough to move substomas to where they nee de o in the organism's body. they face two Solution to problem. body systems that add additional absori orbing area to exchanging Surfaces. A transport System. Osmosis Science-Cells Osmosis is the diffusion of water molecules, from a region where the water molecules are in higher concentration, to a region where they are in a lower concentration, through a partially partially permeable membrane. A dilute solution contains a high concentration of water molecules, while a concentrated solution a low concentration of water molecules. Plant cells use osmosis. contains Active transport Science - Cells active transport is a process that is required to move molecules against a concentration gradient. This process requires energy Aftine bansport is weed in plants and animados. used transport in cells. process Osmosis Science Cells diffusion substances move from a high to low concentration down a concen- tration gradient. Active transport descriptions water moves from a high to a low concentration across a porti. ally permeable membrane and down a concen- Eration gradient Substances move against a con. centration gradient. - Substan Ces moved carbon dioxide, 0₂. H₂0, food substances, wastes (urea) H₂O mineral jons into plant roots, glucose From the gut in to intestinal cels, from where it moves into the blood. energs required NO Yes. Science -Calls Respied posiad one Moscopes Repquind party practical top: osmosis. A communicable disease is one that 59 be passed- from one thing to another. A micro-organisn pathogen. There Bacteria. Science - Infection and Response Viruses bacteria, viruses, fungi, protists. that They When Causes fungi causes They reproduce very fast. Ideal conditions : moist; warm & nutritious. i oxygen. that damage. our tissues. they produce. four main groups of pathogens: They reproduce very fast. Protists toxing and can at only reproduce when inside. cell is full of viruses tissue damage. disease more likely to infect plants. digest dead material. 1 microscopic, worm like organism. calleda it bursts open. the cell. Passed on via: air-borne diszas water-based direct contact sexually bodily fluids. transmitted Measles causes most HIV. Science Infection and Response. fever and Children a red skin rash. Spread by droplets of moisture. Can be fatal are vaccinated Salmonella initially causes flut flu-like symptoms if not treated with. the antiretroviral drugs, the virus system. body's immune immune system lives inside white blood cells and destroys them if not treated. late stage Hiv, or AIDS occurs when the is badly damaged it infections can + no longer deal with other Spread by sharing bodily fluids E.G. blod, unprotected sex. Causes food poisoning. spread by eating infected food, or food prepared in unhygenic conditions. poultry all all vaccinated causes fever, abdominal. attacks cramps, vomiting, diarrhoea. Gonnorrhoea Sexually transmitted disease. Symptoms are thick / green discharge; pain while urinating.. caused by bacterial infection. #6 Science Infection and Response easily treated strains of are appearing. Spread is controlled with antibiotics, or by Malaria and lay eggs mosquito next by penicillin, but now person. Causes fatal episodes of fever. Controlled. by stopping mosquitos which the pathogen. a protist. protist needs a vector which is the mosqui to. mosquito feeds on blood of an infected person and takes the mosquito, breed in the protists. The protists in the salivary glands. When the bites person the Non-Specific defence systems are many resistant barrier methods. eggs end up in that bleeding passive defences, · Constantly stop pathogens getting into vaccinations. 955 Skin, nose, trachea and bronchea, Stomach. body. Our immune system will help fight off any infections that get through our first level defences. It is by our white achieved largely blood cells. There are many different kinds. white blood cels involved in our immune system. of