Anatomy Flashcards
What are the three layers of the heart?
Epicardium (external)
Myocardium (middle) cardiac muscle layer
Endocardium (internal) continuous with endothelium of the blood vessels connecting with the heart
Left atrium position
Forms posterior surface of the heart
Left ventricle position
Forms left border of the heart
Right ventricle position
Forms most the anterior surface of the heart
Right atrium position
Forms right border of the heart
Three layers in blood vessels
Tunica intima - endothelium (internal) Tunica media- smooth muscle and elastic fibres (middle) Tunica adventitia (external) - connective tissue
Arteries supply a ??? Region of the body supplied by a single artery and its branches
A territory
Vasodilation
Relaxation of smooth muscle and widening of lumen to increase blood flow to organs/tisse
Vasoconstriction
Contraction of smooth muscle to reduce blood flow to the organ/tissue
Anastomoses
An anastomosis is where arteries connect with each other without an intervening capillary network
Collateral
An alternative route in any given anastomosis
An end artery
The only arterial blood supply to a given area of the body (no collaterals)
occlusion
Blockage in a blood vessel or hollow organ
Infarction
Irreversible cell death due to hypoxia (lack of oxygen) caused by loss of arterial blood supply
4 parts of the aorta
Ascending aorta (2 branches, left and right coronary artery) Arch of the aorta (3 branches) Thoracic aorta (numerous branches) Abdominal Aorta (3 unpaired midline branches, & 3 paired, bilateral branches)
Venous blood is pumped back to the heart by: (3)
Venous valves to prevent the back blow of blood caused by gravity
Skeletal muscle pump. Skeletal muscles contract in the lower limb
Accompanying veins. Small veins run in pairs or more with in an artery in a sheath. Artery pulsation pushes venous blood along
Superficial veins
They are smaller and run within superficial fascia then drain into deep veins
Deep veins
They are larger and run deep to the deep fascia and in cavities often in NVBs
Two main venous systems
Hepatic portal venous system and systemic venous system
Systemic venous system
Drains venous blood from organs that aren’t absorptive parts of the GI tract and into the superior or inferior vena cavae
Hepatic portal venous system
Drains blood from the absorptive parts of the GI tract and associated organs to the liver for cleaning
Capillary structure
Lined with a single layer of endothelium and have a narrow lumen allowing only one red blood cell through at a time
Function of capillaries
Allow for exchange of gases, metabolites and waste products
What do lymphocytic capillaries collect?
Tissue fluid - fluid that leaks out when blood runs through capillary bed
Where do lymphatic capillaries carry lymph through?
Lymph nodes
Function of lymph nodes
Contain white blood cells to filter our foreign particles and fight infection/cancer
Where is lymph returned into the central veins?
In the venous angles in the root of the neck
The axial skeleton included bones of what? (x3)
Bones of the skull, bones of the neck and bones of the trunk
The appendicular skeleton contains bones of the ..? (x4)
Bones of the pectoral girdle, bones of the upper limbs, bones of the pelvic girdle and bones of the lower limb
The long bone in the arm
The humerus
The two long bones in the forearm
Radius and ulna
The three types of bones in the hand, promixal to distal
Carpal bones, metacarpals and phalanges
The long bone in the thigh
The femur
The two long bones in the leg
Tibia and fibula
The three types of bones in the foot, proximal to distal
Tarsal bones, metatarsals and phalanges
When do bony features develop?
During bone growth
How does a bony feature mould it’s shape?
An adjacent structure applies a force to the developing bone. The adjacent structure is developing at the same time as the bone so the bone has to grow around the other structure.
What is the hole called that is formed in the production of a bony feature?
A foramen
What two components make up the skeleton?
Bones and cartilage
what type of tissue is bone made up of?
hard, connective tissue
four functions of bone
- support and protection of the body
- calcium metabolism
- red blood cell formation
- attachment for skeletal muscles
Difference in cartilage compared with bone
It is less rigid
where is cartilage located?
where mobility is required (at articulations/ joints)
How do bones move?
skeletal muscles contract to move the bones
what is a tuberosity
a large prominence on a bone and is the point where muscles attach
name the three types of joint in order of most to least movability
synovial, cartilaginous and fibrous
why does it hurt so much when a joint is dislocated?
there is an excellent sensory nerve supply around joints
sensations detected by sensory receptors of the joint nerves are:
- pain
- touch
- temperature
- proprioception
what is proprioception?
joint position sense. awareness of the position and movement of the body
where are skeletal muscles found in relation to deep fascia?
skeletal muscles are usually found deep to deep fascia
what is fascia?
connective tissue outside the epimysium that surrounds and separates msucles
what is epimysium?
a tough fibrous connective tissue covering
the longer the muscle fibres, the —— the —- of ——
greater the range of shortening
the longer the muscle, the —- the —- of
greater the potential range of movement produced at joint
fusiform muscles
wider and cylindrically shaped in the centre and taper off at the end (biceps brachii)
circular muscles
circular shape
example of circular muscle
orbicularis oculi
pennate muscle example (obliqueness)
deltoid. like feather
there are at least how many attachments of skeletal muscle to bone?
usually at least 2 points
the two attachment points
the origins and insertions
the only thing a skeletal muscle can do is…
move the origin and insertion closer together during contraction as muscle fibres shorten along the long axis
muscles —- during contraction
shorten
what attaches muscle to bone?
tendons
where are tendons found?
found at either end of the msucle
are tendons contractile or non-contractile?
non-contractile
what is an aponeurosis?
a flattened tendon most commonly associated with flat muscles and attach to soft tissue rather than bone
the direction of movement of the muscle depends on what?
it depends on which side of the joint the muscle spans
what are protective reflexes?
rapid, predictable, involuntary reactions to ‘danger’
what are automatic reflexes?
movement made unconsciously by nervous system and muscles
what are the two main reflexes involving skeletal muscles?
the stretch relflex and the flexion withdrawal reflex
when does the flexion withdraws reflex happen and what happens?
it happens when you touch something potentially damaging and there is a sudden flexion to withdraw from the danger
how are reflex reactions so fast?
the nerve connections are at spinal cord level so the brain is not involed
The stretch reflex (myotatic reflex) is a muscle contraction in response to……..
stretching within the muscle via its tendon
what is a normal strech flex response?
for the muscle to contract
what do deep tendon reflexes protect against?
overstretching
the name of the synapse where the motor nerve communicates with the skeletal muscle
the neuromuscular junction
the route taken by action potentials in deep tendon reflexes is called the?
the reflex arc
a normal stretch reflex indicates that what is working properly? (x6)
- the muscle
- the muscle’s sensory nerve fibres
- the muscles motor nerve fibres
- the spinal cord connections between the two
- the neuromuscular junction
- descending controls from the the brain
Paralysis
when there is a muscle without a functioning motor nerve supply and the muscle cannot contract. The muscle would have reduced tone
spasticity
the muscle has an intact and functioning motor nerve but descending controls from the brain are not working. the muscle would have increased tone
what is muscle tone?
the tension in a muscle at rest
what is atrophy?
atrophy is wasting of the muscles as muscle fibres become smaller, reducing muscle bulk
what causes atrophy?
inactivity due to immobilisation, damage to motor nerve supply or a couch potato
muscle hypertrophy?
skeletal muscle enlarges as each individual myocyte enlarges
what is a myocyte?
a muscle fibre
what is cell hyperplasia?
an increase in the number of cells in an organ or tissue
