2. Support and Movement Biology

3. 14.2Support in mammals in mammals skeleton muscularsystem

4. Contents Why do organisms need a skeleton? What are skeletal tissues? Two parts of skeleton Joints and degree of movement What is skeletal muscles? How is movement achieved? How are plants supported? Multiple choices

5. Why do organisms need a skeleton? n Mammals have endoskeletons for support for producing blood cells Do you know what is the deficiency disease of calcium? Contents

6. Why do organisms need a skeleton? for movement for protection Lungs Heart Contents

7. Why? for storage of minerals Ca 2+ Why do organisms need a skeleton? If the bone is immersed in an acidic solution for about 2 days, what will happen? acid Contents

8. Summary n The mammalian skeleton is important in support, for attachment of muscles and functioning as a lever for movement, in protecting internal organs, in producing blood cells and in storage of calcium. Contents

9. What are skeletal tissues? n The skeletons are made up of bones and cartilages. Transverse section of a compact bones ? Structure of cartilage Which one contains more mineral salts? Contents

10. The skeleton Skeleton consists of : found between bones softer reduces friction during movement bones cartilage hard made up mainly of minerals e.g. calcium phosphate, calcium carbonate

11. What are skeletal tissues? Cartilage Spongy bone containing red bone marrow. Compact bone yellow Cavity containing yellow bone marrow What is the use of the bone marrows? Contents

12. What are skeletal tissues? If my bones are burnt, it will become brittle. Contents

13. Axial skeleton Two parts of skeleton Appendicular skeleton Contents

14. Two parts of skeleton Appendicular skeleton Pectoral girdles Pectoral limbs Pelvic girdles Pelvic limbs Axial skeleton Skull Sternum Ribs Vertebral column Contents

15. Correct Posture to Prevent Injury Plant your feet firmly - get a stable base. Bend at your knees - not your waist. Tighten your abdominal muscles to support your spine. Get a good grip - use both hands. Keep the load close to your body. Use your leg muscles as you lift. Keep your back upright, keep it in its natural posture. Lift steadily and smoothly without jerking. Breathe - If you must hold your breath to lift it, it is too heavy.

16. DO NOT... Lift from the floor. Twist and lift. Lift with one hand (unbalanced) Lift loads across obstacles. Lift while reaching or stretching. Lift from an uncomfortable posture. Don't fight to recover a dropped object. Don't hold your breath while lifting - GET HELP.

17. Muscles are attached to bones through tendons The muscular system muscular system many different sets of muscles the two ends of each muscle are attached to the limb bones through tendons tough sheets of inelastic fibres allow muscles to control the way bones move

18. Joints and degree of movement n 1. Hinge joints Hinge joints allow movement in one plane. Synovial Joint Contents

19. Joints and degree of movement 2. Ball-and-socket joints How many planes of movement do ball-an-socket joints allow? Contents

20. Joints and degree of movement n 2. Ligaments are tough and they prevent dislocation of a joint during movement. pelvic girdle ligaments femur cartilage synovial joint synovial membrane Contents

21. What are skeletal muscles? n Muscle attached to the skeleton. Muscle cells with lots of proteins fibres n Muscles work together with bones to give support and movement to mammals. In aerobic respiration: In anaerobic respiration: Contents Muscles contract powerfully—ie. They work by PULLING. Do you think muscles can stretch themselves—and thus work by PUSHING?

22. Support in mammals in mammals skeleton muscularsystem

23. The muscular system Muscles as part of the support system If the forces of the muscles acting on both sides of two adjacent bones are balanced bones will be kept in the same position A skeleton falls down if let loose because nothing joins the bones together

24. Skeleton without muscles……….. give no support !!

25. How is movement achieved? n 1. Tendons are tough and they connect muscles to bones. muscle tendons Contents

26. n 2. Biceps and triceps are antagonistic muscles involved in the movement of the forearm. They work in pairs and in opposing directions. Contents How is movement achieved?

27. n 3. Contraction of biceps (flexor) bends the forearm while contraction of triceps (extensor) straightens the forearm. triceps relaxes biceps contracts triceps contracts biceps contracts Contents How is movement achieved?

28. Contents How is movement achieved?

29. n 4. Bone act as levers during movement. Movable joints act as the fulcrum. Concentration of muscles creates the effort. contraction of biceps (effort) hand (load) elbow joint (fulcrum) Contents How is movement achieved?

30. How are plants supported? n 1. Support in young plants or non-woody parts of plants is contributed mainly by turgidity of the thin-walled cells in the cortex and pith. Contents

31. 14.3Support in plants in plants Turgidity of cells For non-woody plants Hardness of thick- walled cells in woody plants

32. Turgidity of cells Inside stem of herbaceous plants-(non-woody) water potential of living cells water potential of xylem > water move from xylem to living cells in stems Cells become turgid Turgid cells press against each other to give support to the plant If adequate water supply,

33. Turgidity of cells Inside stem of herbaceous plants water potential of living cells water potential of xylem < Cells become flaccid Flaccid cells cannot provide support to the plant The plant wilts If inadequate water supply,

34. The hardness of thick-walled cells Plants are also supported by thick-walled cells mostly xylem cells which contain lignin As plant grows, older xylem tissues in stems are pushed inwards and become wood.

35. Water absorbed by osmosis turgid Water lost by osmosis flaccid Wilting occurs In this case, transpiration is faster than absorption of water. Contents How are plants supported?

36. n 2. Support in woody stems is contributed mainly by rigidity of the lignified cells in xylem. Contents How are plants supported?

37. Multiple choices 1. Which muscles contract to effect a change form the condition shown in Diagram I to that in Diagram II? P, Q and R P, Q and S P, R and T Q, S and T Contents

38. Multiple choices 2. Which of the following functions are carried out by bone W? (1) Producing red blood cells (2) helping in ventilation of the lung (3) protecting internal organs (1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3) Contents

39. Multiple choices 3. Which of the joints X, Y and Z allow(s) movement between the bones? Y only Z only X and Y only Y and Z only Contents

40. Multiple choices 4. Which of the following correctly describes the functions of structures A and B? holding the bones transmitting force together to the bone acting as a pivot protecting the joint protecting the joint preventing dislocation of the joint transmitting force acting as a pivot to the bone Structure A Structure B Contents

41. Multiple choices 5. The diagram below shows a man at a certain stage of swimming: Which of the following combinations correctly describes the conditions of his arm muscles at this stage? Left armRight arm Biceps Triceps contracted relaxedrelaxed contracted relaxed contractedcontracted relaxed contracted relaxedcontracted relaxed relaxed contractedrelaxed contracted Contents

42. Multiple choices 6. The diagram below shows a human arm holding a weight: The length of EF is shorter than the length of WF. What is the advantage of this arrangement? The biceps would not become fatigue easily. This would make the biceps stronger than the triceps. Less energy would be used by the biceps in supporting the weight. A small contraction of the biceps would move the weight through a large distance. Contents

43. Multiple choices 7. Which structures are parts of the axial skeleton? 3 1, 2 and 3 1, 2 and 4 1, 3 and 4 2, 3 and 4 Contents

44. Multiple choices 8. Which of the following correctly lists the structures protected by the different parts of the skeleton? 3 1 2 3 brain aorta stomach ears aorta heart brain spinal cord heart ears spinal cord stomach Contents

45. Multiple choices 9. The diagram below shows a model of a movable joint: Which of the following combinations is correct? Type of joint represented by the model Example hinge jointknee joint hinge jointshoulder joint ball and socket jointshoulder joint ball and socket jointKnee joint Contents

46. Multiple choices 10. The diagrams below show three sets of bones of the human skeleton: Ball and socket joint can be formed between 1 and 3. 1 and 4. 2 and 3. 2 and 4. 1 Contents

47. Multiple choices The model below illustrate the movement at the elbow joint: 11. Which of the following occurs when Q is shortened? shortenedraised shortenedlowered stretchedraised stretched lowered P S Contents

48. Multiple choices The model below illustrate the movement at the elbow joint: 12. The model is useful for demonstrating the movement of the upper arm. that the joint allows 360º movement. that the biceps is stronger than the triceps. the actions of a pair of antagonistic muscles. Contents

49. Multiple choices Diagram I shows some muscles attached to the leg bones. Diagram II shows the posture of a person sitting on a stool. Which muscles in the person’s leg are contracted when he maintains the posture shown in the diagram II? muscles 1 and 2 only muscles 1 and 3 only muscles 2 and 4 only muscles 3 and 4 only 13. 1 2 Contents

50. Multiple choices 14. Which of the following are involved in maintaining our postures? (1) skeletal muscles (2) bones (3) ligaments (4) nervous system (1) and (2) only (3) and (4) only (1), (2) and (3) only (1), (2), (3) and (4) Contents

51. Multiple choices 14. Which of the following is not a function of the mammalian skeleton? storage of fat storage of calcium destruction of red blood cells production of white blood cells Contents

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