BTEC Level 3 Applied Science Unit 1 Biology 2023 with 100% questions and answers

plasma membrane a microscopic membrane of lipids and proteins (Phospholipid bilayer) that forms the external boundary of the cytoplasm of a cell or encloses a vacuole, and that regulates the passage of molecules in and out of the cytoplasm. Golgi apparatus A system of membranes that modifies and packages proteins for export by the cell Vesicle Small membrane-bound sac that functions in moving products into, out of, and within a cell. Ribosomes site of protein synthesis - 70s in prokaryotic cells - 80s in eukaryotic cells Mitochondrion bean-shaped organelle that supplies energy (ATP) during the process of respiration , to the cell and has its own ribosomes and DNA. Centrioles Cell organelle that aids in cell division in animal cells only Nucleus the central and most important part of an object, movement, or group, forming the basis for its activity and growth. Contains DNA Nucleolus Makes ribosomes Smooth Endoplasmic Reticulum An endomembrane system where lipids are synthesized, calcium levels are regulated, and toxic substances are broken down. Rough Endoplasmic Reticulum System of internal membranes within the cytoplasm. Membranes are rough due to the presence of ribosomes. functions in transport of substances such as proteins within the cytoplasm Lysosomes An organelle containing digestive enzymes (lysozymes) cell wall A rigid layer of nonliving material that surrounds the cells of plants and some other organisms. Chloroplasts Site of photosynthesis Vacuole Cell organelle that stores materials such as water, salts, proteins, and carbohydrates Amyloplast starch storage Plasmodesmata An open channel in the cell wall of plants through which strands of cytosol connect from adjacent cells pits openings in the lateral walls of xylem cells allowing water and nutrients to leak into surrounding tissues. resting potential electrical charge across the cell membrane of a resting neuron (-70mV) action potential the change in electrical potential (due to changes in membrane permeability to sodium and potassium ions) associated with the passage of an impulse along the membrane of a muscle cell or nerve cell. Magnification equation Image size/actual size light microscope (LM) An optical instrument with lenses that refract (bend) visible light to magnify images of specimens. Resolution restricted by the wavelength of light