Full Notes.pdf

Topic 1 Cell Structure and Organisation Animal cell Plant cell  Learning outcomes (a) Identify and state the functions of the following cell structures (including organelles) of typical plant and animal cells from diagrams, light micrographs and as seen under the light microscope u...

Topic 1 Cell Structure and Organisation Animal cell Plant cell  Learning outcomes (a) Identify and state the functions of the following cell structures (including organelles) of typical plant and animal cells from diagrams, light micrographs and as seen under the light microscope using prepared slides and fresh material treated with an appropriate temporary staining technique Cell wall Cell membrane Cytoplasm Nucleus Cell vacuoles chloroplasts Organelles that can be seen under the light microscope Cell membrane Cytoplasm Found in animal and plant cells Nucleus Cell wall Large, sap-filled vacuole Unique to plant cells in plant cells Chloroplasts  Organelles function Present in both animal and plant cells Cell Membrane Partially permeable, controls substances entering or leaving the cells. Controls cellular activities such as growth, repair, and cell division. Nucleus (singular) Nuclei (plural) Contains DNA Made up of 90% water and contains dissolved protein, sugars, enzymes. Cytoplasm Embedded with organelles (eg mitochondria, RER, SER, Golgi body). Sites of most cellular activities. Stores water, food, dissolved mineral salts, and other substances Vacuole Animal cell: small, numerous vacuoles known as vesicles 🡪 transport substances within and out of the cell. Plant cell: one large permanent vacuole. Maintain rigidity and shape of plant cells (tugor pressure)  Organelles function Present ONLY in plant cells Organelle Functions Fully permeable. Cellulose cell wall Protects cell from injury Gives the cell its regular shape, prevent it from bursting Chloroplast Contains chlorophyll, which traps light for photosynthesis  Learning outcomes (b) Identify and state the functions of the following membrane systems and organelles from diagrams and electron micrographs: Endoplasmic reticulum Golgi body Mitochondria Ribosomes  Organelles function Present in both animal and plant cells Ribosomes Can either be attached to RER or free floating. RER Site of protein synthesis Ribosomes are attached to the Rough membrane (thus rough) endoplasmic reticulum RER is involved in protein synthesis Ribosome Smooth Synthesises fats and steroids such as sex endoplasmic hormones reticulum also contains enzymes that detoxify drugs and poisons. golg It stores, sorts and modifies i Golgi body substances made by the ER, and SER body packages them in vesicles to be secreted out of the cell Path of protein (via vesicles): RER > Golgi Body > Outside of the cell  Organelles function Present in both animal and plant cells RER Site for cellular (aerobic) Mitochondria respiration to release energy (”powerhouse of the cell”) Ribosome Energy is used to carry out cellular activities, including protein synthesis golg SER i body  Learning outcomes (c) compare the structure of typical animal and plant cells  Compare the structure of typical animal and plant cells Animal cell Plant cell Cell membrane Nucleus Cytoplasm Mitochondria Ribosomes Endoplasmic reticulum Golgi body Vacuoles Small, numerous Large, central Cellulose cell wall Chloroplast  Learning outcomes (d) Explain how the structures of specialized cells are adapted to their functions  Specialised Cells RED BLOOD CELLS Function Contains hemoglobin, which binds with oxygen and transports it from the lungs to all parts of the body / other body tissues  Specialised Cells RED BLOOD CELLS Adaptation Lacks nucleus Greater capacity for more and other hemoglobin > organelles High concentration of hemoglobin > Allows it to transport more oxygen Flattened, Increases surface area to biconcave shape volume ratio for faster/ efficient diffusion of oxygen Renders flexibility, allows RBC to squeeze through narrow blood capillaries > Reach all tissues > Ensures efficient and adequate oxygen delivery  Specialised Cells XYLEM Function Conduct water and mineral salts from the roots to the leaves of the plant Mechanical support of plants  Specialised Cells XYLEM Adaptation Absence of Ensure continuous and protoplasm and smooth passage of water cross-walls through the lumen Deposition of Strengthens vessel walls, lignin on the prevents vessel from cell walls collapsing  © Hee Xin Organ System Wei Cell Tissue Organ Organ system Organism Different tissues A group of Different A group of cells of The most working together functionally- organ systems the same type that basic unit to perform a related work together are found near each of a living specific function or organs for survival other and carry out organism a group of the same function functions