Download the presentation here Additional notesCellsMade up of:-protoplasm- cellulose cell wall (non-living and only in plants) Protoplasm consists of: - nucleus which controls cellular activities and consists of - nuclear envelope - nucleoplasm - chromatin (made up of DNA) - nucleolus - cytoplasm which surrounds the nucleus and where most life processes occur and consists of - mitochondria - sites of energy release - vacuoles - contain water and food substances - chloroplasts - in plant cells only - centrioles - in animal cells - cell surface membrane which is the partially permeable, outer covering enclosing the cytoplasm Plant and Animal cellsBoth plant and animal cells have- nucleus - cytoplasm - cell membrane - mitochondria - energy is released here by respiration Only plant cells have - cell wall - large vacuole - chloroplasts Specialised cells1. Root hair cell in plants is adapted to do its job of taking in water and nutrients by having- a large surface area - a thin cell membrane 2. Red blood cell which carries oxygen around the body have - no nucleus and a large surface area (concave shape) - allows maximum area for oxygen carriers - have haemoglobin to carry oxygen 3. White blood cell which fights disease and some make antibodies - their adaptations: - irregular shape and they can change shape to squeeze out of blood vessels and get to the site of infection - others have cytoplasm which can flow making it possible for the cell to change shape and hence surround and engulf bacteria Cells, tissues, organs and systemsTissue: a group of cells make up a tissueeg heart muscle tissue Organ: a group of tissue makes up an organ eg heart System: a group of organs makes up a system eg circulatory system Organism: a group of systems make up an organism eg Humans |
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