Anatomy Flashcards
What is the axial skeleton?
The bones located at the midline of the body (skull, neck, trunk)
What is the appendicular skeleton?
Bones lateral to the midline (pectoral girdle, upper limbs, pelvic girdle, lower limb)
Where is the humerus?
Superior to the radius and ulna in the arm
What are the two bones of the forearm and which is which?
Radius (lateral) and ulna (medial)
Describe the bones of the hand.
Carpal bones (wrist)
Metacarpals (phalanges)
Phalanges (fingers)
Where is the femur?
In the leg superior to the tibia and fibula
What are the bones in the lower leg?
Tibia (medial) and fibula (lateral)
What are the bones of the foot?
Tarsal bones (hindfoot/ midfoot)
Metatarsals (forefoot)
Phalanges (toes)
What are bony features?
Bony features develop during bone growth and aid the bone in their function.
How are bony features formed?
1- an adjacent structure (nerve,tendon,blood vessel, bone) applies a force to the developing bone moulding it’s shape accordingly
2- an adjacent structure is developing at the same time as the bone so the bone has to grow around the other structure forming a foramen (hole)
What makes up the skeleton?
Bone and cartilage
Describe bone.
-hard connective tissue
Is important in support and protection of the body organs, calcium metabolism, red blood cell formation and attachment for skeletal muscles
Describe cartilage.
Cartilage is less rigid than bone and is located where mobility is required - at articulations (joints)
What are the different types of joints?
Synovial (most mobile, least stabile)
Cartilaginous
Fibrous (least mobile, most stable)
What are the sensations detected by the sensory receptors of the joint nerves ?
Pain, touch, temperature, proprioception (sense of spacial awareness)
What can happen when joints are dislocated?
The arteries can be damaged, dangerously compromising blood supply distal to the joint
where is skeletal muscle found?
Epidermis (epithelium) Dermis (collagen/elastic fibres) Superficial fascia (adipose tissue) Deep fascia (fibrous tissue) Skeletal muscle
Describe skeletal muscle
- Produce movement
- usually found deep to fascia
- tough fibrous connective tissue covering
What are the types of skeletal muscle?
Circular, pennate, fusiform, flat with apponeurosis, quadrate
- Longer muscle fibres have greater potential range of shortening and range of movement
What are origins and insertions ?
Skeletal muscle is usually attached at at least 2 areas
The origin(s) is one side of a joint while the insertion(s) is the other side
(The origin is usually proximal)
Describe skeletal muscle contraction.
The only thing a skeletal muscle can do is move the origin and insertion closer together during contraction. This is due to shortening of the muscle fibres.
What is a tendon?
When skeletal muscle attaches to bone it is called a tendon. It is non- contractile
What is an aponeurosis?
A flattened tendon most commonly associated with flat muscles which attaches muscle to soft tissue rather than bone.
What does the direction of movement depend on?
Which joint is spanned, the long axis of the muscle, the aspect of the joint that is spanned and the shapes of the articular surfaces of the joint
What does the shape of the articular surface tell you about possible movement?
The shape of the articular surface determines how much movement is possible (eg shoulder joint has a socket allowing circumduction but he elbow doesn’t)
Describe the directional movement of the deltoid.
The posterior fibres allow extension of the shoulder, the middle fibres allow abduction of the shoulder and the anterior fibres allow flexion in the shoulder
What are the two types of reflex ?
Stretch reflex and flexion withdrawal reflex
What is the flexion withdrawal reflex?
When u touch something potentially damaging a sudden flexion occurs to withdraw from the danger by the reflex arc through the spinal cord.
What are stretch reflexes?
When a tendon hammer is used to apply a brief sudden stretch to the muscle via it’s tendon, the normal reflex is to contract which results in a brief twitch of the muscle belly or movement in a normal direction. These reflexes are protective against over stretching.
Describe the deep tendon reflex (reflex arc)
The sensory nerve from the muscle secrecy’s the stretch and tells the spinal cord > the signal travels across the synapse in the spinal cord between sensory and motor nerves > the motor nerve passes message for muscles to contract > muscle contracts.
The brain prevents this from being overly brisk.
What does a normal stretch reflex tell you?
That’s the muscle, sensory nerve fibres, motor nerve fibres, spinal cord connection, neuromuscular junction and the descending controls from the brain all function normally.
What is paralysis?
When a muscle doesn’t have a functioning motor nerve and cannot contract. This will cause reduced muscle tone.
What is spasticity ?
When the muscle has an intact and functioning motor nerve and it is the descending controls from the brain that aren’t working. They will have increased muscle tone.
What is atrophy?
=wasting of muscles
The muscle fibres become smaller and reduce in size as a result of inactivity. This can happen as a result of immobilisation after a fracture, damage to motor nerve supplies or lack of movement.
What is hypertrophy?
When skeletal muscle enlarges (each individual myocyte enlarges)
Where is the normal site of fertilisation?
The ampulla