Biology Topic 2: Organisation

33 flashcards · Biology · by Marli Williams

1. Cells

   The basic building blocks of all living organisms.

2. A Tissue

   A group of cells with a similar structure and function.

3. Organ systems

   A group of organs working together to perform a specific function.

4. Organism

   A group of organ systems which work together - therefore forming an organism.

5. Digestive System

   Several organs work together to digest and absorb food.

6. Mouth (digestive system)

   Food is mechanically digested Amylase is found here

7. Oesophagus (digestive system)

   Food travels through this to the stomach

8. Stomach (digestive system)

   Churns food HCl acid kills pathogens Protease is found here

9. Small intestine (digestive system)

   Absorbs digested food molecules Amylase Protease Lipase

10. Large intestine (digestive system)

    Absorbs water Produces Faeces

11. Liver (digestive system)

    Produces Bile (emulsifies fats and changes low pH from the stomach to alkaline for the Small intestine)

12. Gall Bladder (digestive system)

    Stores Bile (emulsifies fats and changes low pH from the stomach to alkaline for the Small intestine)

13. Bile is made in the liver and stored in the gall bladder. It is alkaline to neutralise hydrochloric acid from the stomach. It also emulsifies fat to form small droplets which increases the surface area. The alkaline conditions and large surface area increase the rate of fat breakdown by lipase.

14. Pancreas (digestive system)

    Produces Enzymes such as: Amylase Protease Lipase

15. Organ

    A group of tissue working together to perform a specific function.

16. Enzymes

    Natural biological catalysts which catalyze specific reactions in living organism based on the shape of their active site. Made from Proteins

17. Enzymes work at an optimum pH and temperature. They'll denature if the pH / temperature is too far from the optimum - the active site deforms

18. Lock and Key Theory

    Enzymes will only bind to one specific substrate. It's Active site is a specific shape or a specific substrate.

19. Amylase

    Breaks down Starch to Maltose Salivary glands, Pancreas, Small intestine

20. Protease

    Breaks down Proteins to Animo Acids Stomach, Pancreas, Small intestine

21. Lipase

    Breaks down Lipids (fats & oils) to Fatty Acids + Glycerol Pancreas, Small intestine

22. Products of Digestion are used for?

    Respiration Building new... Carbohydrates Proteins Lipids

23. Required Practical: Testing for Sugars, Starch and Proteins

24. Food Tests: Benedict's for Sugars: light blue to brick-red Iodine for Starch: orange-brown to blue-black Biuret for protein: blue to lilac-purple

25. Required Practical: Effect of pH on Enzymes

    Independent Variable: pH buffer solution Dependent Variable: Time it takes for iodine to change color Control Variables: Volume of starch, amylase and buffer solution used

26. Ways to improve Required Practical 5 (enzymes + pH)

    Control temperature using a water bath Using a colorimeter to track progress in color change - reduces chances of parallax error

27. The Heart

    An organ that pumps blood around the body in a double circulatory system. The right ventricle pumps blood to the lungs where gas exchange takes place. The left ventricle pumps blood around the rest of the body.

28. Flow of blood through the double circulatory system.

    Deoxygenated blood from body to Vena Cava Through Right Atrium Pumped out of the Right Ventricle to lungs Through the Pulmonary Artery Oxygenated blood from the lungs via Pulmonary Vein Through Left Atrium Pumped out of the Left Ventricle to the body Through the Aorta

29. The natural resting heart rate is controlled by a group of cells located in the right atrium that act as a pacemaker. Artificial pacemakers are electrical devices used to correct irregularities in the heart rate.

30. The Lungs

    An organ which exchanges gases.

31. Structure of the lungs

    Trachea to Bronchi to Bronchioles to Alveoli

32. Arteries Function and Adaptations

    Function: Transport Blood away from the heart at a high pressure Adaption: Thick walls of elastic and muscle fibers to withstand high pressure Narrow lumen to maintain high blood blood pressure

33. Vein Function and Adaptations

    Function: Transport Blood towards the heart at a low pressure Adaption: Larger Lumen to accommodate for low pressure Valves to prevent the backflow of blood due to low pressure Thin walls of elastic and muscle fibers due to low pressure