B1-5,7

Cell differentiation and Specialisation

• Diffrentiation is the process in which cells become specialised for a specific job.
• - They develop different subcelluar structures
• - Turn into different types of cells
• - Have specific Functions
• - Plants dont ever lose the ability to diffrentiate
• -Replacing and repairing cells
• - Undiffrentiated cells are called stem cells
• -Sperm Cells
• *Long tail, Head full of mitochondria, Enzymes in the head to digest through the egg
• - Nerve Cells
• *Electrical Impules, Branched connections, Connect to other nerve cells
• - Muscle Cells
• *Long,space to contract, Lots of mitochondria, to give energy

Mitosis

• 1.Growth and DNA Recplication
• - In a cell that is not dividing, the DNA is spread out in long strings
• -Grow and increase subcellular structures
• -Duplicate DNA
• 2.Mitosis
• -Chromosomes line up ain the center and cell fibers pull them apart
• -Two arms go to opposite ends
• -Membranes form around each set of chromosomes
• -Nucleus is divided
• -Cytoplasm and cell membrane divide
• Two new Daughter cells

Questions

• 1. Describe the events of the cell cycle that need to occur before mitosis can begin?
• 2. What are chromosomes?
• 3. How many pairs of chromosomes are there in a human cell?
• 4. Describe the process of mitosis
• 5. What is differentiation?
• 6. What is it called when cells are undifferentiated?
• 7. What can mature animals cells be used for?
• 8. What are sperm cells specialised for? Give on part of the body that helps it do this.
• 9. What are muscle cells specialised for?
• 10. Give the function of a muscle cell.

Blood Vessels

• Arteries:
• - Pump blood away from the heart
• - They have to go through a high pressure
• - Walls are strong and elastic
• - Walls are thick compared to the lumen
• - Thick layers of muscle to make them strong
• - Elastic Fibres to allow them to spring back
• Capillaries
• - Very small
• - Arteries branch into capillaries
• - Carry blood really close to the cells to exchange substances with them
• - Permeable walls so that they can diffuse easily
• - Provide food and oxygen
• - Take away C02
• - One cell thick walls to increase the rate of diffusion by decreasing the distance

Blood Vessels

• Veins
• -Capillaries join up with veins
• - Lower Pressure so walls don't need to be thick
• - Big lumen to help blood flow
• - Valves to keep the blood flowing in the right direction

Transpiration and Translocation

• Transpiration
• -Made of dead cells
• -Joined end to end no walls in the middle
• - Carry water and mineral ions from roots to stem and leaves
• - This movement is of xylem
• Translocation
• - Elongated living cells with small pores to allow cell sap to follow through
• - Food substances are transported made in leaves to the rest of the plant for use and storages
• - Both Directions
• - This movement is of Phloem

Transpiration and stomata

• Light intensity
• - Brighter light higher transpiration rate
• - Stomata close in the dark because the plant cant photosynthesise
• Temperature
• - The warmer it is the faster transpiration rate
• - Warm particles have more energy to evaporate and diffuse out of the stomata
• Air Flow
• - The better airflow the greater transpiration rate
• - Water vapour is swept away maintaining the low concentration, so diffusion will occur faster
• Humidity
• - The drier the air the faster transpiration
• - if air is humid there's already lots of water so there isn't a difference. Diffusion happens fastest if there's a really high concentration and a really low concentration in another.

Questions

• 1. What pressure do Arteries carry the blood under?
• 2. How are the walls in veins built up?
• 3. What are capillaries branches off?
• 4. What helps the arteries stretch?
• 5. What is a lumen?
• 6. What helps the blood flow in one direction?
• 7. What is a Xylem made of?
• 8. What does phloem transport?
• 9. What is translocation?
• 10. What is transpiration?
• 11. How does light intensity affect the rate of transpiration?
• 12. Why does a better air flow help?
• 13. How does temperature help transpiration?

Viral

• Measles
• - Droplets from infected persons sneeze or a cough
• - Red skin rash and fever
• - Complication or be minor
• - Vaccinated if you are young
• Tobacco mosaic Virus
• - Plants
• - Mosaic patterns on a leaf
• - Discoloured parts of leaves
• - The plant can't carry out photosynthesis
• HIV
• - Sexual contact
• - exchanging bodily fluids
• - sharing needles cause this
• - Flu-like symptom
• - antiretroviral drugs to help it
• - Immune cells are attacked

Fungal

Protist

Developing Drugs

Questions

Photosynthesis

Respiration and Metabolism

Aerobic and Anaerobic Respiration

Questions

Controlling blood glucose

Controlling fertility

Adrenaline and Thyroxine

Questions

Abiotic/Biotic Factors

Using Transects

Water Cylce

Carbon Cycle

Waste Management

Maintaining Ecosystems

Maintaining Biodiversity

Questions