Musculo-skeletal System. Overview of musculo-skeletal system Musculo-skeletal system is composed of: ◦ Muscles ◦ Bones ◦ Cartilage ◦ Ligaments ◦ Tendons.

Musculo-skeletal SystemMusculo-skeletal System

Overview of musculo-skeletal Overview of musculo-skeletal systemsystem

Musculo-skeletal system is composed of:◦Muscles◦Bones◦Cartilage◦Ligaments◦Tendons

TASKTASKWhat does the musculoskeletal

system do?◦Write down some ideas.

What does the What does the musculoskeletal system do?musculoskeletal system do?Its functions is to allow:

◦Movement◦Maintenance of posture◦Support◦Protection of internal organs◦Heat production

Muscular system Muscular system

MusclesMusclesThree main types of muscle:

1. Cardiac Heart muscle

2. Smooth Found in internal organs

3. Skeletal Also known as voluntary muscles Attached to bones on the skeleton Over 600 in the body

Types of voluntary Types of voluntary musclesmusclesMuscles work in ANTAGONISTIC pairs: ◦As one muscle contracts, the other

muscle relaxes.

There are different types of muscles. Each has a different function and they usually work in pairs.

Extensors and FlexorsAdductors and AbductorsLevators and DepressorsConstrictors

Types of voluntary musclesTypes of voluntary muscles

Extensors ◦ open a joint

Adductors ◦ move body part inwards

Levators ◦ move body part upwards

Constrictors (circular muscles so do not have a pair; also called sphincter muscles)◦ Close openings

Flexors

Abductors

Depressors

Here are some functions the pairs of muscles. What is the function of the other half to the pair?

Types of voluntary musclesTypes of voluntary muscles

Extensors ◦ open a joint

Adductors ◦ move body part inwards

Levators ◦ move body part upwards

Constrictors (circular muscles so do not have a pair; also called sphincter muscles)◦ Close openings

Flexors ◦ close a joint

Abductors◦ move body part outwards

Depressors◦ move body part

downwards

Muscles work in ANTAGONISTIC pairs: As one contracts the other relaxes.

A synovial jointA synovial joint

Synovial jointSynovial joint

Task: Main Parts of a Task: Main Parts of a Synovial JointSynovial Joint

Look up in the textbook or using internet resources to find the function of the following parts of a synovial joint\;

BoneArticular CartilageSynovial membraneSynovial fluidLigamentsTendons

Main Parts of a Synovial Main Parts of a Synovial JointJointBone:

◦ Mixture of protein, collagen and minerals e.g. calciumArticular Cartilage:

◦ Smooth tissue which protects bones and stops them grating by reducing friction

Synovial membrane◦ Lines the joint capsule and secretes synovial fluid

Synovial fluid◦ Acts like a lubricant, helps bones slide over each other

Ligaments◦ Holds bones together and prevents over extension of joint

Tendons◦ Connects muscle to bone

Movement of the forearmMovement of the forearm

Movement of the forearmMovement of the forearmMuscles get shorter when they

contract◦Big biceps when you flex your arm!

Muscles get longer and more stretched out when they relax◦Flat biceps when you put your arm

down!

Task: making a model armTask: making a model armMake the model arm and

complete the worksheet.

◦Follow all instructions on the sheet

Answers to questionsAnswers to questionsWhen the biceps contract and the triceps

relax the forearm moves upwards

When the triceps contract and the biceps relax the forearm moves downards

We call this an Antagonistic Pair, meaning as one muscle contracts the other relaxes.

Label the parts of the forearm.

Answers to forearm Answers to forearm labellinglabelling

Skeleton Skeleton

Skeleton functionsSkeleton functionsIts functions is to allow:

◦Movement◦Support◦Protection of internal organs

Major organs and their Major organs and their skeletal protection: Copy & skeletal protection: Copy & CompleteCompleteBody system Organprotected Part of the skeleton

Nervous system

Respiratory system

Cardiovascular system

Renal system

Digestive system

Reproductive system

Major organs and their Major organs and their skeletal protectionskeletal protectionBody system Organ protected Part of the

skeleton

Nervous system Brain Skull

Spinal Cord Spinal column

Sense organs e.g. Ears, eyes

Skull

Respiratory system

Lungs & bronchi Rib cage, spinal column, sternum

Cardiovascular system

Heart & major blood vessels

Rib cage, spinal column, sternum

Renal system Kidneys Rib cage and spinal column

Digestive system Liver Rib cage

Reproductive system

Ovaries, uterus Pelvis