7. Run for your life
7.a Muscles and respiration
Structure of joints
Bone/skeleton
● Support and protect body parts
● Strong and hard
● Bone cells embedded in matrix of collagen and calcium salts
● Light so easier to move
● Articulate with other bones
● Provide anchorage for muscles
● Function
- Provide support and protection for body and organs
- Blood cell production
- Movement
- Storage of calcium
- Endocrine regulation
Cartilage
● Flexible / elastic
● Made up of cells called chondrocytes
● Two types:
1. Hyaline cartilage - smooth
2. White fibrous - tensile strength, between vertebrae and bone
● Function
- Smooth to reduce friction
- Allows smooth movement
- Support
- Shock absorbance
Ligaments
● Joins bone to bone
● Keeps bones in correct alignment
● Elastic
● Fibrous tissue
● Strong
Tendons
● Joins muscle to bone
● Fibrous tissue
● Strong but inelastic
, 7. Run for your life
Types of muscle
Smooth muscle
● Works under control of the involuntary nervous system
● Causes slow contractions of many internal organs
● Long, spindle shaped cells
● No striations
● Contractions are slow and long
● Fibres fatigue very slowly
Cardiac muscle
● Only found in the heart
● Striated muscle
● Contains interconnected fibres to ensure a co-ordinated wave of contraction
● Myogenic - contract spontaneously
● Does not fatigue
● Short contractions over a long time period
Skeletal muscle
● Attached to skeleton
● Involved in locomotion
● Voluntary nervous system
● Contracts rapidly and fatigues quickly
● Capable of strong contractions
Muscles and movement
● Skeletal muscles are attached to bones by tendons. Ligaments attach bones to other
bones. Skeletal muscles contract and relax to move bones at a joint.
● Muscles work in antagonistic pairs working in opposite forces, while one contracts
the other relaxes. Each antagonistic pair contains one extensor muscle (contracts to
extend the joint) and one flexor muscle (contracts to reverse the movement).
Muscle fibres
● Skeletal muscle is made up of large bundles of long cells called muscle fibres. The
cell membrane of the muscle fibre is called the sarcolemma and the cytoplasm is
called the sarcoplasm.
● Sarcolemma folds inwards across the muscle fibre and into the sarcoplasm to form
transverse (T) tubules which help spread electrical impulses allowing it to reach all
parts of the muscle fibre.
● A network of internal membranes called the sarcoplasmic reticulum runs through
the sarcoplasm. The sarcoplasmic reticulum stores and releases calcium ions
(needed for muscle contraction)
● Muscle fibres contain many mitochondria to provide the ATP needed for contraction.
● Muscle fibres are multinucleate (contain many nuclei)
● Muscle fibres have lots of long, cylindrical organelles called myofibrils.
● There are two types of muscle fibres, slow twitch and fast twitch:
7.a Muscles and respiration
Structure of joints
Bone/skeleton
● Support and protect body parts
● Strong and hard
● Bone cells embedded in matrix of collagen and calcium salts
● Light so easier to move
● Articulate with other bones
● Provide anchorage for muscles
● Function
- Provide support and protection for body and organs
- Blood cell production
- Movement
- Storage of calcium
- Endocrine regulation
Cartilage
● Flexible / elastic
● Made up of cells called chondrocytes
● Two types:
1. Hyaline cartilage - smooth
2. White fibrous - tensile strength, between vertebrae and bone
● Function
- Smooth to reduce friction
- Allows smooth movement
- Support
- Shock absorbance
Ligaments
● Joins bone to bone
● Keeps bones in correct alignment
● Elastic
● Fibrous tissue
● Strong
Tendons
● Joins muscle to bone
● Fibrous tissue
● Strong but inelastic
, 7. Run for your life
Types of muscle
Smooth muscle
● Works under control of the involuntary nervous system
● Causes slow contractions of many internal organs
● Long, spindle shaped cells
● No striations
● Contractions are slow and long
● Fibres fatigue very slowly
Cardiac muscle
● Only found in the heart
● Striated muscle
● Contains interconnected fibres to ensure a co-ordinated wave of contraction
● Myogenic - contract spontaneously
● Does not fatigue
● Short contractions over a long time period
Skeletal muscle
● Attached to skeleton
● Involved in locomotion
● Voluntary nervous system
● Contracts rapidly and fatigues quickly
● Capable of strong contractions
Muscles and movement
● Skeletal muscles are attached to bones by tendons. Ligaments attach bones to other
bones. Skeletal muscles contract and relax to move bones at a joint.
● Muscles work in antagonistic pairs working in opposite forces, while one contracts
the other relaxes. Each antagonistic pair contains one extensor muscle (contracts to
extend the joint) and one flexor muscle (contracts to reverse the movement).
Muscle fibres
● Skeletal muscle is made up of large bundles of long cells called muscle fibres. The
cell membrane of the muscle fibre is called the sarcolemma and the cytoplasm is
called the sarcoplasm.
● Sarcolemma folds inwards across the muscle fibre and into the sarcoplasm to form
transverse (T) tubules which help spread electrical impulses allowing it to reach all
parts of the muscle fibre.
● A network of internal membranes called the sarcoplasmic reticulum runs through
the sarcoplasm. The sarcoplasmic reticulum stores and releases calcium ions
(needed for muscle contraction)
● Muscle fibres contain many mitochondria to provide the ATP needed for contraction.
● Muscle fibres are multinucleate (contain many nuclei)
● Muscle fibres have lots of long, cylindrical organelles called myofibrils.
● There are two types of muscle fibres, slow twitch and fast twitch:
