Cells pt 2

• Living cell provides energy from respiration for active transport.
• Organelles of typical plant and animal cells include chloroplasts, cell membrane, cell wall, cytoplasm, cell vacuoles, and nucleus.
• Mitochondria, ribosomes, endoplasmic reticulum, and Golgi body are membrane systems and organelles that can be identified from diagrams and electron micrographs.
• The functions of the organelles identified above can be stated.
• The structure of typical animal and plant cells can be compared.
• The relationship between cell function and cell structure can be stated for absorption (root hair cells), conduction and support (xylem vessels), and transport of oxygen (red blood cells).
• Each living cell consists of living material called protoplasm.
• Protoplasm is made up of cell surface membrane, nucleus, and cytoplasm.
• Protoplasm is jelly-like, containing mainly water and many other substances.
• Animal cells contain a nucleus, cell membrane, cytoplasm, and vacuoles.
• The nucleus of an animal cell contains chromatin or chromosomes, controls cell activities such as cell repair and growth, and controls cell division.
• The cell membrane of an animal cell is a thin, partially permeable layer around the cell that controls movement of substances in and out of the cell.
• Cytoplasm is a gel/jelly-like substance made up mainly of water that acts as a medium for most chemical activities of the cell to occur and contains enzymes and organelles.
• Mitochondria are small, rod-shaped organelles with a highly folded inner membrane where aerobic respiration takes place and energy is released.
• Ribosomes are small, round structures that can be attached to ER or found freely in the cytoplasm and are the site where protein synthesis takes place.
• Vacuoles are fluid-filled spaces enclosed by a membrane that exist temporarily in animal cells and store substances such as water and food temporarily.
• Endoplasmic Reticulum is a network of flattened spaces lined with membranes, synthesizes fats and detoxifies the cell, and ribosomes attached to its outer surface synthesizes proteins for transport out of the cell.
• Golgi Apparatus is a series of membranes that modifies and packages substances made by ER into vesicles for secretion out of cell.
• Plant cells have structures similar to an animal cell except for the presence of a cellulose cell wall and chloroplasts.
• A tissue is a group of similar cells which work together to perform a specific function.
• Red blood cells are elastic and can turn bell-shaped, allowing the cell to move/squeeze through small blood vessels.
• An organ system is made up of different organs working together to perform a main body function.
• The cell wall surrounds the entire plant cell, surrounding the cell membrane and is made of cellulose.
• Xylem vessels have lignin deposited on the walls, strengthening the wall of the xylem vessels and preventing them from collapsing.
• Differentiation is the process by which a cell becomes specialised for a specific function.
• Root hair cells have a long and narrow protrusion/extension of an epidermal cell to increase surface area to volume ratio for faster absorption of water and mineral salts from soil.
• Chlorophyll enables light energy to be trapped and be converted into chemical energy stored in food (glucose) during the process of photosynthesis.
• Xylem vessels transport water and mineral salts from roots up the stem and to the leaves, providing mechanical/structural support for the plant when bundled together.
• Specialised tissues include animal blood tissue which transports food and oxygen, muscle tissue which produces movement, nerve tissue which transmits impulses, epithelial tissue which protects cells, plant epidermal tissue which forms and protects the surface of cells, xylem tissue which transports water and mineral salts, and phloem tissue which transports food.
• When haemoglobin combines with oxygen, oxyhaemoglobin is formed.
• Red blood cells contain haemoglobin (red pigment) in cytoplasm which transports oxygen from the lungs to all parts of the body.
• Root hair cells have a large vacuole with concentrated cell sap and cell membrane, and a lower water potential, allowing absorption of water from the soil.
• Cell sap contains water and dissolved substances such as sugars, mineral salts and amino acids.
• The absence of a nucleus allows more haemoglobin to be contained and hence transport more oxygen.
• Red blood cells have a circular biconcave shape to increase surface area to volume ratio for faster diffusion of gases in and out of cell.
• Chloroplasts have stacks of disc-like structures which contain the green substance called chlorophyll.
• Adaptation contains haemoglobin to allow oxygen to bind to/with RBC to form oxyhaemoglobin.
• Root hair cells absorb water via osmosis and mineral salts from soil via diffusion.
• Xylem vessels have an absence of cross walls and protoplasm to enable water to move easily through the lumen (central space).
• A plant cell has one large central vacuole containing cell sap, which is enclosed by a membrane called the tonoplast.