SUPPORT SYSTEM IN ANIMALS PP SLIDES part 1

SUPPORT SYSTEM IN ANIMALS PP SLIDES

1. UNIT 6: SUPPORT SYSTEMS IN ANIMALS

2. The three main types of skeletons are : Hydrostatic skeletons (lack hard parts) Endoskeletons (internal hard parts) Exoskeletons (external hard parts) 1. DIFFERENT TYPES OF SKELETONS

3. Hydrostatic Skeletons A hydrostatic skeleton consists of fluid held under pressure in a closed body This is the main type of skeleton in most cnidarians, flatworms, nematodes, and annelids

4. HYDROSTATIC SKELETONS CNIDARIA NEMATODE FLATWORMS ANNELIDA

5. Exoskeletons An exoskeleton is a hard encasement deposited on the surface of an animal Exoskeletons are found in most molluscs and arthropods Arthropod exoskeletons are made of cuticle and can be both strong and flexible The polysaccharide chitin is often found in arthropod cuticle

6. EXOSKELETONS ARTHROPODS MOLLUSC

7. ENDOSKELETONS An endoskeleton consists of hard supporting elements, such as bones. Endoskeletons are found in sponges, echinoderms, and chordates A mammalian skeleton has more than 200 bones Some bones are fused ; others are connected at joints by l igaments that allow freedom of movement.

8. ENDOSKELETONS ECHINODERMATA SPONGES CHORDATA

9. 2. THE HUMAN SKELETON

10. 2. THE HUMAN SKELETON

11. HUMAN SKELETON AXIAL SKELETON APPENDICULAR SKELETON 1. CRANIUM/ SKULL 2. VERTEBRAL COLUMN 3. THORAX PECTORAL GIRDLE 2. PELVIC GIRDLE

12. a. AXIAL SKELETON: i )Human Skull Consist of 28 bones It consists of flat bones that are connected on the sides by immovable joints called sutures . In babies not all the bones of the skull make contact with each other and fontanels are formed.

13. The lower jaw bone ( Mandible ) is the only movable bone of the skull – Upper jaw ( Maxilla) is not moveable . The large opening at the base of the skull is called the foramen magnum – it is where the spinal cord enters the skull

14. Human Skull

15. a. AXIAL SKELETON: ii)VERTEBRAL COLUMN Consists of 33 bones called vertebrae . 24 vertebrae are individual single bones . 9 vertebrae are fused to form the sacrum and coccyx. Cartilage disks are found between vertebrae. The s-shaped structure of the vertebral column and the disks absorb shock and help to protect the spinal cord. \

16. The first vertebrae – Atlas – carry the weight of the skull, allows the head to nod. 2 nd vertebrae – Axis – allows head to move to the side

17. a. AXIAL SKELETON:ii ) VERTEBRAL COLUMN Vertebrae is divided into 7 Cervical vertebrae 12 Thoracic vertebrae 5 Lumbar vertebrae 5 fused vertebrae = sacrum 4 fused vertebrae = coccyx

18. a. AXIAL SKELETON: iii) THORAX Consists of the sternum, 12 pairs of ribs and thoracic vertebrae . It protects the heart and lungs. First 7 pairs of ribs are directly attached to the sternum by cartilage – called true ribs. Next 5 pairs – false ribs – last 2 pairs of false ribs are not attached to the sternum – called floating ribs Intercostal muscles found between ribs – aid in breathing process.

19. a. AXIAL SKELETON: iii) THORAX True ribs False ribs Floating ribs sternum

20. b. APPENDICULAR SKELETON Made up of the shoulder ( pectoral girdle ), arms, hips ( pelvic girdle ) and legs. 126 bones . Function: Movement

21. APPENDICULAR SKELETON 1. Pectoral girdle and arm

22. APPENDICULAR SKELETON 2. Pelvic girdle and leg

23. FUNCTIONS OF A SKELETON Support Movement Protection Blood cell production Storage

24. Blood cell production The skeleton is the site of haematopoiesis, which takes place in red bone marrow. Haematopoiesis is the formation of blood cellular components.

25. 4. STRUCTURE OF A LONG BONE A long bone is an elongated bone consisting of a body ( diaphysis ) and two terminal parts ( epiphyses ), such as found in the leg and arm bones (femur, radius, phalanges and others).

26. 4. STRUCTURE OF A LONG BONE

27. STRUCTURE OF A SYNOVIAL JOINT SYNOVIAL JOINT IS A MOVABLE JOINT

28. Different types of synovial joints are: Ball and socket joint Hinge joint Pivot joint Gliding joint

29. BALL AND SOCKET JOINT: Joints of the hips and shoulders Allows rotating movement of arms and legs

30. HINGE JOINT: Joints of the elbows, knees, fingers and toes Only allows movement in one direction.

31. PIVOT JOINT: Joints between atlas and axis One bone turns on another

32. Joints of the wrist and ankles The flat surface of one bone glides over the surface of a bone next to it. GLIDING JOINT:

33. JOINT DISORDERS Do research ( self study ) on the following disorders, you have to be able to briefly explain what each of them are (will not be marked but there will be question in the exam and semester test about it) Dislocation Sprains Arthritis Osteoarthritis Rheumatoid arthritis

34. 6. MACRO STRUCTURE OF SKELETAL MUSCLES Epimysium : Surrounds entire muscle Perimysium : Surrounds bundles of muscle fibres Endomysium : Surrounds individual muscle fibres

35. Sarcolemma: Muscle cell membrane Myofibrils : Threadlike strands within muscle fibres Actin (thin filament) Myosin (thick filament) MICRO STRUCTURE OF SKELETAL MUSCLES

36. SKELETAL MUSCLES Muscles are attached to bones by means of tendons. Skeletal muscles produce movement by contracting. Muscles occur in pairs which work antagonistic against each other. When one contracts the other relaxes .

37. MOVEMENT OF THE ARM