Cells

• An independent variable is the variable that you change
• The dependant variable is the thing you are measuring
• The controlled variables re kept the same
• All living organisms are made up of cells
• A scientific observation is looking carefully and in detail at an object and drawing conclusions
• A microscope is made up of an eyepiece, objective lens, stage, slide, light, fine focus and course focus
• Total magnification = eyepiece lens magnification × objective lens magnification
• The four components found in an animal cell are a nucleus, cell membrane, cytoplasm and mitochondria
• Cytoplasm- a jelly like substance where chemical reactions take place
• Cell membrane- barrier around the cell that controls what comes in and out of a cell
• Nucleus- controls the cell and contains genetic material
• Mitochondria- where respiration happens
• Additionally to an animal cells components, plant cells also have a cell wall, vacuole and chloroplasts
• Cell wall- support structure for the cell, made of cellulose
• Vacuole- contains cell sap; this keeps the cell firm
• Chloroplasts- where photosynthesis happens; contains chlorophyll (green coloured substance)
• A specialised cell is suited out to carry out a specific function
• Nerve cells cary electrical impulses around the body. Their long and thin shape have connectiosn at each end so that they can join other nerve cells.
• Red blood cells don't have a nucleus so that they have a larger surface area
• Sperms cells are streamlined and have a long tail which allows them to move through liquid
• Leaf cells are long and thin and are packed with chloroplasts so that they can absorb more energy
• Root hair cells have a large surface area to absorb water and minerals
• All cells in your body need glucose and oxygen
• Carbon dioxide is a substance that moves out of a body cell as a waste product of respiration
• Diffusion is when particles in an area of high concentration move to an area of low concentration
• Unicellular organisms is made up of just one cell. It is not a plant or animal