Biology Paper 1

• Eukaryotic cells


  Contain a nucleus and other organelles that are bound by membranes.
• prokaryotic cell


  cell lacking a nucleus and most other organelles
• Nucleus


  A part of the cell containing DNA and RNA and responsible for growth and reproduction
• Cytoplasm


  A jellylike fluid inside the cell in which the organelles are suspended
• cell membrane


  A cell structure that controls which substances can enter or leave the cell.
• Mitochondria


  An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur.
• Ribosomes


  site of protein synthesis
• cell wall


  A rigid structure that surrounds the cell membrane and provides support to the cell. made of cellulose
• Vacuole


  Cell organelle that stores materials such as water, salts, proteins, and carbohydrates
• Chloroplast


  An organelle found in plant and algae cells where photosynthesis occurs
• Chromosomal DNA


  stores information in units called genes
• Plasmid DNA


  A ring of DNA capable of replicating itself. Found in bacteria commonly.
• flagellum


  A long, hairlike structure that grows out of a cell and enables the cell to move.
• Multicellular organisms


  Organisms composed of many cells (Ex. tissue, humans, etc.)
• sexual reproduction


  A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents
• egg cell


  female reproductive cell
• sperm cell

  male reproductive cell
• ciliated epithelial cells


  Cells in the trachea which have microscopic hairs (cilia) growing from them.
• microscope


  An instrument that makes small objects look larger
• light microscope


  An optical instrument with lenses that refract (bend) visible light to magnify images of specimens.
• electron microscope


  microscope that forms an image by focusing beams of electrons onto a specimen
• Magnification


  the ratio of an object's image size to its real size
• Enzymes


  Catalysts for chemical reactions in living things
• Substrate


  reactant of an enzyme-catalysed reaction
• active site


  The part of an enzyme or antibody where the chemical reaction occurs.
• factors which affect the rate of reaction

  -temperature

  -pH

  -substrate concentration
• Denature


  A change in the shape of a protein (such as an enzyme) that can be caused by changes in temperature or pH (among other things).
• Pepsin


  Enzyme that breaks down proteins into smaller polypeptide fragments
• Amylase


  enzyme that breaks down starch
• lock and key


  The idea that enzymes are specifically shaped to fit only one type of substrate
• Carbohydrase


  enzyme that breaks down starches into sugars
• Protease


  enzyme that digests protein
• Lipase


  enzyme that breaks down fat
• glycogen synthase


  An enzyme that joins together lots of chains of glucose molecules to make glycogen
• Starch test


  Iodine is used. If it's present, the sample goes from brow/orange to blue/black
• Lipids test


  Emulsion test. combine substance with ethanol and pour into water. if it's present they will show as milky
• Proteins test


  Biuret test. Add KOH to make substance alkali. add CuSO₄. If they're present, the solution will turn purple
• Diffusion


  Movement of molecules from an area of higher concentration to an area of lower concentration.
• Osmosis


  the net movement of water molecules across a partially permeable membrane from an area of high water concentration to an area of lower water concentration.
• Partially permeable membrane


  a membrane that allows only certain substances to pass through