cells and transport- topic 1

• once a cell becomes differentiated it only expresses the genes that produce the proteins characteristics for that type of cell. differentiation cells are important as they are able to perform a specialised function in the body
• Only in plant cells: cell wall, vacuole, chloroplasts
• I’m both plant and animal cells cytoplasm, nucleus, cell membrane, mitochondria, ribsomes
• active transport is the movement of molecules across a partially permeable membrane from a lower concentration to a higher concentration this requires energy
• Vacuole is filled with sap to help keep the cell turgid
• Diffusion is the movement of particles from an area of high concentration to an area of low concentration
• mitochondria respiration takes place here
• Cell membrane controls movement of substances in and out of the cell
• Nucleus contains the genetic material which controls the activity of the cell
• Cell wall strengthens the cell
• factors affecting rate of diffusion: temperature (higher the temperature faster the rate) concentration gradient (bigger the concentration gradient faster the rate) SA:V ratio (larger the SA:V ratio the fast the rate of diffusion)
• Advantages of stem cells: treating patients with otherwise untreatable conditions, helps improve overall medical research, helps grow organs for transplants
• Disadvantages of stem cells: no guarantee on success rate, difficulty finding donors, mutations in stem cells
• Cytoplasm most chemical processes take place here carried out by enzymes
• Ribosomes protein synthesis takes place here
• Chloroplasts photosynthesis takes place here
• Osmosis is a special case of diffusion involving water molecules moving from an area of high water potential to areas of low water potential through a selectively permeable membrane
• levels of organisation, organelles (nucleus, mitochondria etc) cells (plant,animal) tissues (group of cells) organs (group of tissue) system (group of organs)