Common Requirements of living things - ANIMALS – Chapter 5

1. Common Requirements of living things - ANIMALS – Chapter 5

2. Movement of substances into & out of unicellular organisms Passive diffusion in and out

3. CellSpecialisation in Simple Multicellular Organisms Sponge feeding

4. Cell Specialisation in Simple Multicellular Organisms Cnidarians feeding

5. Cell Specialisation in Simple Multicellular Organisms

6. Cell Specialisation in Vertebrate Multicellular Organisms

7. Cell Specialisation in Vertebrate Multicellular Organisms

8. The different systems! Animal’s bodies are composed of different systems, each system has it’s own functions. All together these systems work together to enable the animal to survive. http://video.nationalgeographic.com/video/player/science/health-human-body-sci/human-body/human-body-sci.html

9. Obtaining nutrients and energy • Animals are heterotrophs must consume food in order to obtain nutrients and energy. • Animals are adapted to obtain food in a variety of ways python vs croc

10. Required Nutrients • Carbohydrates - source of immediate energy for all living organisms. The monosaccharide glucose is broken down to make ATP in cellular respiration. • Lipids- Fats and oils required for cell membranes, hormones and vitamins. • Amino Acids - The building blocks of proteins. The body can make some amino acids but others it can’t make these are the 9 essential amino acids. Need to be regularly eaten. • Vitamins - Organic compounds needed for cellular processes, e.g. making enzymes. • Minerals- needed for structural components and for enzyme molecules.

11. Two Types of Digestion. Physical digestion. • Food physically broken it down into smaller pieces in order to increase surface area and enable maximum efficiency of chemical digestion.

12. The Digestive System • Ingestion- intake of food into the body • Digestion- physical and chemical breaking down of food • Absorption- nutrient molecules move into the circulatory system and ultimately into the cells. • Egestion/ Elimination- removal of waste from the body

13. Chemical Digestion Breakdown of macromolecules by enzymes- made in the gut, salivary glands and pancreas into molecules small enough to be absorbed through the alimentary lining. Amylases- Break down carbs Proteases- Break down protein Lipases- Break down lipids

14. Introduction to the Human Alimentary System animation http://health.howstuffworks.com/human-body/systems/digestive/adam-200086.htm

17. Digestion • Stomach - majority of digestion occurs • Mechanical digestion occurs as the muscles crush and move the food. • Chemical digestion also occurs in the stomach, with the secretion of gastric juices with have enzymes that break down the food. • Small intestine -further digestion occurs but only on proteins and carbohydrates to break them down into their amino acid building blocks. Digestion-video.htm

18. Absorption Most occurs in the small intestine. Food at it’s smallest is then absorbed by the cells of the intestine and passed along to the blood stream.

20. Task • Draw a poster of the human digestive system, using the image on page 110. • Label the drawing and explain the role of each word. • Colour in the parts of the digestive system that are involved in ingestion, digestion, absorption and egestion.

21. Other mammals • Different diets require different digestive systems. • Breaking down cellulose requires the enzyme cellulase. • Mammals can’t make this enzyme. • Cows have a 4 chambered stomach. • They chew and then regurgitate their food and chew it again before sending it to the rumen where heaps of cellulose digesting bacteria live and allow the breakdown of the cellulose to occurs.

22. Carnivore v Herbivore Caecum: a pouch extension at the junction of the small & large colon which in herbivores contains cellulose digesting bacteria. Herbivorus mammals with higher fibre diets may have larger caecums to maximise the opportunity for cellulose digestion by bacteria.

23. Digestion in birds Most (not all) birds have : • a crop for temporary storage • a glandular part the proventriculuswhich secretes mucus , HCl & enzymes • a muscular gizzard which may contain grit or small stones which grinds and mixes the food and enzymes etc.

24. The Circulatory System

25. Internal transport systems • distribute nutrients, gases and collect and remove wastes. • transport hormones and blood. • Blood is also vital in defence, immunity, blood clotting and transfer heat around the body of mammals and birds.

26. Open Circulatory System No specialised transporting fluid. Instead interstitial fluid is moves freely around the body before eventually returning to the heart. Very low blood pressure and long circuit times.

27. Closed circulatory systems • Blood is enclosed in a system of vessels surrounding a muscular heart. • Blood is returned very rapidly to the heart and there is a higher blood pressure. • Blood is also separated from the interstitial fluid vessel walls allowing the blood to be used for transport and defence. • Small molecules like nutrients, gases, water and waste are freely exchanged by diffusion across capillaries. • Because larger molecules(blood proteins) can’t diffuse out of the blood, this exerts osmotic effect drawing water back into the blood.

28. Closed Circulatory System

29. Closed System 2 Chambered Heart

30. Closed System 3 Chambered Heart

31. Closed System 4 Chambered Heart

33. Mammalian Transport Systems • There are 2 transport systems in mammals: • The blood circulatory system- majority of the animal’s transport needs. • The lymphatic drainage system-open system that maintains osmotic and fluid balance in tissues and in immune defence.

34. Internal transport systems Features of effective transport systems • Large surface area for exchange both with the environment and internally. • A reliable and responsive way of moving fluid(blood) around the body. • A fluid that can carry the maximum amount of material. • A way to regulate transport according to the needs of the body.

35. The human circulatory system • A fluid material in which substances are transported; blood • A system of blood vessels or spaces throughout the body in which fluid moves • A pump such as the heart that pushes through the blood vessels and spaces. THE CARDIOVASCULAR SYSTEM = heart and blood vessels

37. Blood

39. Red blood cells • Biconcave • Very flexible • No nucleus • Packed with haemoglobin • Main function is transporting gases

40. White blood cells • Larger than red blood cells • About 1WBC to every 700 RBC • Several types but all involved in defence. • Phagocytes: remove debris and fight infection • Lymphocytes: produce antibodies.

41. Platelets Fragments of cells, important in preventing blood loss and promoting blood clotting.

42. Arteries andVeins • Arteries carry blood away from the heart. • Veins carry blood towards the heart. • Arteries and veins have the same number of walls but arteries have more muscular walls and veins more elastic walls.

43. Blood Movement in the Veins

44. Veins Arteries • Pressure in veins is much lower than in arteries. • Blood moves along due muscles compressing the veins. • Veins have lots of one way valves, that push the blood towards the heart. • In the legs the blood has to be returned against gravitational pressure. • The negative pressure in the lungs assists in drawing the blood up from the legs. • Because of their thicker walls they can withstand greater pressure. • Arteries flow into arterioles that then flow into capillaries. • Blood pressure decreases as blood flows further along.

45. Capillaries • Tiny, many branched blood capillaries provide a vast surface for exchanging blood. • Most cells are no more than 1mm from the nearest capillary. • Same diameter as a red blood cell, so they fit in one by one. • When the wall of a red blood cell presses on the capillary wall there is an exchange of oxygen and carbon dioxide. http://www.youtube.com/watch?v=CjNKbL_-cwA

46. Mammalian Heart Four chambers: The Atria (singular: atrium): • Two top chambers, thinner walls. The Ventricles: • Two bottom chambers, thicker walls. One way valves ensure blood flows in one direction. The heart is very coordinated first the atria contract forcing the blood into the ventricles then the ventricles contract.

49. Blood Circulation 2 pathways- • To and from the lungs. The pulmonary pathway. • To and from the rest of the body. The systemic pathway. • The heart • Veins and arteries • Pulmonary vessels • Systemic vessels • Capillaries • Blood

50. Blood pressure • Caused by the contraction of the ventricles. • The right ventricle is much thinner than the left so the pressure caused by the left ventricle is greater than the right. • In the arteries blood pressure changes with every heart beat, this is the pulse you hear on your wrist. • The higher systolic pressure occurs when the ventricles contract. • The lower diastolic pressure occurs when the ventricles relax.