Musculoskeletal system Flashcards
Give examples of the following bones: Long bones Short bones Flat bones Irregular bones
Long bones- arms and legs
Short bones- wrists and ankles
Flat bones- Ribs, skull bones
Irregular bones- facial bones, vertebrae
List two types of bone tissue
Compact bone (centre of long bone) Spongy bone (end of long bone)
What does the axial skeleton include?
Head (cranial/facial bones) and the vertebrae
Appendicular bones
Include the exterior bones eg arms and legs
What do ligaments connect?
Give an example
These connect bone to bone to form joints
What do tendons connect?
These connect bone to muscle
Where are coronal sutures?
They start at the top centre of the frontal bone and run down either side of the fronts bone (forehead) to either side of the eye sockets
What is the bone at the front of the skull (forehead) called?
Frontal bone
What are the bones called at the top of the head?
Left and right parietal bones
Which bone is at the back of the skull?
The occipital bone
What suture marks out the occipital bone from the parietal bones?
The lambdoid suture
What suture divides the parietal bones?
The Sagitta suture
Which bone is below the parietal bone on either side?
The temporal bones
What suture divides the parietal bone and the temporal bone?
The squamous suture
What suture runs along the top of the frontal bone and meets in a t-shape with the Sagittal suture?
The coronal suture
What bone at the bottom of the spine is part of the pelvis?
The sacrum
What tail-like structured bone is joined to the bottom of the sacrum?
The coccyx
What bone structure makes up the shoulders?
The pectoral girdle
Where are the radial bones located?
The large bones of the forearm below the elbow
What is the name of the long bone behind the radial bone at the back of the lower arm?
The ulna
Bone in the thigh
Femur
Two bones in lower leg
Inner- tibia
Outer-fibula
What are cartilaginous joints?
Joints made of cartilage that unite bones
What are the two types of cartilaginous joints?
Symphyses
Synchondrosis
What is an example of a symphyses joint?
Type of cartilaginous joint
Pubic symphysis
What is the pubic symphysis?
This is a cartilaginous symphyses joint that joins the left and right pubic bones
It becomes flexible in pregnancy for an easier delivery
What are synovial joints?
Joint cavities between two bones filled with synovial fluid
Common types of synovial joints include
Pivot (elbow) , ball and socket (hip/shoulder), hinge (elbow/knee)
What is a fibrous joint?
Dense connective tissue made mainly of collagen eg sutures in the skull
What terms describe the joint movement where a bone can move forward and backwards?
Forward- Extension
Backwards-flexion
What are bone cells called
Osteocytes
What is the periosteum?
Vascular connective tissue covering bones
Four functions of bones
Organ protection
Muscle attachment (act as levers for muscles which are attached to periosteum)
Blood cell production (in red bone marrow)
Mineral storage eg calcium
How does endochondral bone form?
These start as hyaline cartilage models and are replaced with bone. Cartilage tissue is invaded by blood vessels and osteoblasts that first form spongy bone (primary ossification centre in the diaphysis).
Later osteoblasts beneath the periosteum lay down compact bone outside the spongy bone (secondary ossification).
Hyaline cartilage forms between the two ossification layers.
What is the shaft of a long bone called?
Diaphysis
What are the ends of bones called that form joints with adjacent bones?
Epiphyses
What terms describe the movement where bones move towards or away from each other?
Abduction- out
Adduction- in
What is the outer covering of bone called?
The periosteum
What are the three types of muscle?
Smooth
Skeletal
Cardiac
What are muscles made up of in size order
Fascicles-muscle fibres-myofibrils-thick and thin filaments (myofilaments )
How does intramembranous bone form?
Osteoblast cells deposit bone tissue around themselves enclosing themselves into compartments called lacunae. The cells are then called osteocytes (within bone).
What proteins are the thick and think myofilaments made up of?
Thin- actin
Thick-myosin
What are the other two proteins in muscle?
Tropinin and tropomyosin
How do actin and myosin interact?
Myosin heads buns to actin filaments to form an actin-myosin crossbridge
In a muscular response, what period occurs before the period of contraction (after stimulation)? What comes after the period of contraction?
Before - latent period
After-period of relaxation
Summation
If a skeletal muscle is stimulated and another stimulation is applied before the relaxation is complete, the stimulation’s combine to create a larger contraction
What is the name of the muscle fibre membrane?
Sarcolemma
Muscle fibre cytoplasm
Sarcoplasm
What do myofilaments make up?
Bigger filaments called myofibrils
What does the sarcomere functional unit extend from?
Z line to z line
Dark stripes in sarcomere are called
A bands
What are the I bands?
Light stripes in the sarcomere
What are transverse tubules?
Extensions of cell membrane that penetrate into the centre of skeletal and cardiac muscle cells
Which area stores and releases calcium ions for muscle contraction
Sarcoplasmic reticulum
What neurotransmitter is released from the end of a motor neurone?
Acetylcholine
What on actin molecules do myosin heads bind to?
Myosin binding sites
How does the muscle fibre shorten?
Myosin heads form crossbridges on actin molecule and then actin-myosin crossbridge bends, pulling the actin filament. It then releases and attaches to the next binding site and repeats, drawing in the actin molecule.
What two molecules does muscles contraction require?
Calcium and ATP
Where is acetylcholine released from and to in muscle stimulus for contraction?
The motor neurone’s synaptic vesicles into the synaptic cleft
What happens when the acetylcholine binds to receptors in the synapse?
If the stimulus reaches the threshold for an action potential, a muscle impulse spreads around the sarcolemma surface down the t tubules to the sarcoplasmic reticulum which releases calcium ions into the sarcoplasm
What does the increase of calcium ions in the sarcoplasm do?
Interacts with troponin and tropomyosin (associated with actin) which move from the myosin binding sites so they are free for myosin heads to bind
What do troponin and tropomyosin do at rest?
Cover the myosin binding sites (until calcium activated them to move)
What enzyme disposed of acetylcholine?
Acetylcholinesterase
Which muscle types are involuntary vs voluntary
Involuntary- cardiac, smooth
Voluntary- skeletal
Tetany
When many stimulation’s occur in high frequency causing involuntary contraction of muscles
3 types of muscle
Skeletal muscle
Cardiac muscle
Smooth muscle
Where are smooth muscles located
Walls of Blood vessels walls of organs
Where are cardiac muscles located
Walls of the heart
Purpose of skeletal muscle
Allow movement of bones at joints, posture maintenance
Purpose of smooth muscle
Movement of organs, vasoconstriction
What is the purpose of cardiac muscle
Allow heart to pump
What are Antagonist and agonist muscles? Give example
Antagonistic pairs of muscles in which one contracts as the other relaxes to lift or release a bone eg arm - to left, bicep contracts and tricep relaxes
Osteoclasts
Bone reabsorbing cells
Ischiococcygeus muscle runs from
Ischial spines to coccyx
The contractile unit of skeletal muscle cells is known as?
The sarcomere
Ventral
Near the abdomen
Medial
In the middle
Lateral
To the side of the body
Distal
Away from the centre of the body
Proximal
Near the centre of the body
Sagittal plane on body
Down centre of body along sagittal suture downwards
Transverse plane
Across abdomen horizontally dividing body in half
Coronal plane
Across body from shoulder to shoulder and dividing body in half
