Anatomy Flashcards
How can the skeleton be split?
Into the axial component and the appendicular component
What does the axial component of the skeleton consist of?
Skull, spine and thorax
What does the appendicular component of the skeleton consist of?
The upper and lower limbs
What is the anatomical position?
- Standing erect with feet flat
- Straight back with eyes and head forward
- Arms by the side with forearms and hands facing forwards
- Eyes focused at infinity
Where is the coronal plane?
The vertical plane which divides the body into ‘belly and back’
Where is the Sagittal plane?
It divides the body into left and right
Where is the axial plane?
It gives a view as if you are looking up from the feet
Define superior
Above
Define inferior
Below
Define lateral
Further from the sagittal plane
Define medial
Closer to the sagittal plane
Define superficial
Closer to the surface
Define deep
Further from the surface
Define anterior
Closer to the front of the body
Define posterior
Closer to the back of the body
Define proximal
Closer to the starting point
Define distal
Further from the starting point
Define ipsilateral
Same side of the body
Define contralateral
Opposite side of the body
Define supine
Variation of the anatomical position where the person is flat on their back
Define prone
Variation of the anatomical position where the person is lying face down
What are the three types of joints?
Fibrous, cartilaginous and synovial
What are some properties of synovial joints?
- Allow free movement between the bones they join
- Majority of limbs are synovial
What is the structure of fibrous joints?
- Bone —> fibrous tissue —> bone
- Bones in fibrous joints are united by fibrous tissue
- There is no joint cavity
- The amount of movement depends on the length of the fibres
What are the two types of cartilaginous joints and what are their features?
- The bones in a cartilaginous joint are united by cartilage
- In primary structure, there is some flexibility
- In secondary structures, there is some strength provided by fibrocartilage
What is the structure of primary cartilaginous joints?
Bone —> hyaline cartilage —> bone
What is the structure of secondary cartilaginous joints?
Bone —> hyaline cartilage —> fibro-cartilage —> hyaline cartilage —> bone
What does the knee joint consist of?
A synovial hinge joint with articulation between the lateral and medial condyles of the distal femur, the lateral and medial condyles of the tibia and the patella
What does the meniscus of the knee do and what is it made of?
- For protection
- Made from fibrocartilage
Where does hyaline cartilage cover in the knee and what does it allow?
Articulating surfaces and allows smooth movements
What do the collateral ligaments do?
Stabilise the femur and tibia in the coronal plane
What will a lateral force to the knee do?
Strain or tear the medial (tibial) collateral ligament
What will a medial force to the knee do?
Strain or tear the lateral (fibular) collateral ligament
What does the ACL and PCL do?
Prevent excessive movements in the sagittal plane
What does the ACL join?
Attaches posterior part of the lateral condyle of the femur and the anterior part of the tibial plateau
What does the ACL prevent?
Excessive forward movements of the tibia in relation to the femur
What does the PCL join?
Attaches the posterior tibial plateau and the anterior part of the medial condyle of the femur
What does the PCL prevent?
Excessive movement of the femur anteriorly in relation to the tibia
How can you injure the ACL?
Excessive twisting or anterior movement of the tibia when fully weight bearing
How can you injure the PCL?
Excessive forward movement of the femur on the tibia (usually when flexed)
What are the 3 types of muscle?
Skeletal, smooth and cardiac
What is the structure of smooth muscles, where is it present and is it voluntary?
- Narrow, tapered rod-shaped cells
- Has non-striated, uninucleated fibres
- Occurs in walls of internal organs and blood vessels
- Involuntary control
What is the structure of cardiac muscles, where is it present and is it voluntary?
- Striated, tubular, branched uninucleated fibres
- Occurs in walls of the heart
- Involuntary control
What is the structure of skeletal muscles, where is it present and is it voluntary?
- Striated, tubular, multinucleated fibres
- Usually attaches to skeleton
- Voluntary
Where is cardiac muscle present?
The heart
Where is smooth muscle present, what is it controlled by and what does it contribute to?
- Hollow organs and blood vessels
- Controlled by the autonomic nervous system
- Linked with involuntary bodily functions e.g. BP, digestion and micturition
What is micturition?
Control of the bladder
What is the function of skeletal muscle?
To move the skeleton. It is under voluntary control
How is the skeletal muscle joined to skeleton?
By two or more attachments to the bony skeleton, usually with at least one joint between the attachments
What happens when skeletal muscles contract?
Brings the two attachments (to the skeleton) closer and causes a movement
What is an attachment with less movement in skeletal muscle?
Origin. The other side is insertion
Is there always an intervening tendon between the muscle and bone?
Yes
Why might long tendons be present in the body?
To ensure muscle doesn’t crowd certain areas of the body e.g. the muscle in the lower arm for the hands
What are the 8 muscle structures?
Convergent, circular, multipennate, parallel, fusiform, unipennate, bipennate
Name an example of a convergent muscle
Pectoralis major
Name an example of a circular muscle
Orbicularis oris
Name an example of a multipennate muscle
Deltoid
Name an example of a parallel muscle
Sartorius
Name an example of a fusiform muscle
Biceps branchii
Name an example of a unipennate muscle
Extensor digitorum longus
Name an example of a bipennate muscle
Rectus femoris
Where may dendrites originate?
The spinal cord
How many muscle fibres are supplied when fine control is needed?
One or two
How many muscle fibres are supplied when fine control isn’t needed?
Thousands
Define synergistic
Act together
Define antagonistic
Act against each other
Define flexion
When a joint becomes more bent. In the back, this is forwards
Define extension
When a joint becomes less bent. In the back, this is backwards
Define rotation
Where the angle of two bones doesn’t change but the axis of one of the bones rotates relative to the other e.g. turning of the head to look sideways
Define abduction
Movement away from the midline
Define adduction
Movement towards the midline
Define lateral flexion
When the upper body bends to the side. This also happens in the neck
Define pronation
When the palm of the hand faces posteriorly (downwards)
Define supination
When the palm of the hand faces anteriorly (upwards)
Define protraction
To move forwards
Define retraction
To move backwards
Define opposition
When the thumb and little finger meet
Define inversion
The sole of the foot faces onwards towards the other foot
Define eversion
The sole of the foot faces outwards
Do the upper and lower limbs develop the same way embryologically?
Yes. They have similar arrangements of blood vessels, muscles and bones
What is the general anatomical structure of the lower and upper limbs?
- 1 large bone proximally
- 2 parallel bones distally
- Reduction in bone size as you go distally with an increase on bone number
What are the components of the hindbrain?
- Medulla oblongata
- Pons
- Cerebellum
What are the parts of the midbrain?
- Tectum
- Cerebral peduncle
What are the divisions of the forebrain?
- Diencephalon
- Telencephalon
What are the components of the diencephalon?
- Thalamus
- Hypothalamus
What are the components of the telencephalon?
- Cerebral cortex
- Basal ganglia
Define rostral
Towards the front (the beak)
Define caudal
Towards the tail
What is the white matter compromised of?
Collections of nerve fibres (axons and dendrites) with few or no neuronal cell bodies
What is the grey matter of the CNS compromised of?
Aggregations of neuronal cell bodies and their local processes
What is the neuropil?
Dense network of nerve fibres, branches and synapses
What are nuclei/ganglia?
Collections of nerve cells within the brain
What is the cortex?
The outer surface of the brain, which is formed by flatter sheets of neurones
Briefly describe the structure of the dura
- Latticed appearance
- Cranially, has an outer endosteal layer and a inner meningeal layer
Briefly describe the structure of arachnoid matter
- A loose connective tissue consisting of collagen, elastin and reticulin
- Poor vasculation
- Tight junctions
Briefly describe the structure of the pia matter
- Pial cells lay on the CNS. This is formed by astrocytes and their basement membrane
- There is a connective tissue part of the pia
Where is CSF present?
The subarachnoid space
What does the central sulcus separate?
The frontal and parietal lobes
What does the lateral sulcus separate?
The temporal from the parietal and frontal lobes
What is the insula?
Forms the floor of the lateral sulcus
What is the opercula?
The parts of the temporal, frontal and parietal lobes that overlie the insula
What is the corpus callosum?
A large bundle of white matter connecting the two hemispheres
Where are the olfactory tracts located?
On the inferior surface of the frontal lobes
Where are the optic nerves?
Passing backwards and medially, converging in the midline to form the optic chiasma, then backwards and laterally two form the optic tracts
Where are the mammillary bodies found?
Behind the optic chiasma
Where is the hypothalamus?
Behind the optic chiasma up to and including the mammillary bodies
What is the only part of the diencephalon visible on the outside of the brain?
Hypothalamus
What are the crura cerebri?
Two large masses of white matter emerging behind the mammillary bodies on each side
What is the interpenduncular fossa?
Space between the crura roofed over by arachnoid
Where is the pons?
Behind where the crura meet in the midline
Where is the cerebellum?
Two lobes, one either side of the medulla and a central vermis joining the two hemispheres
Where is the medulla oblongata?
Runs from the caudal border of the pons to the spinal cord
What is the function of the left parietal lobe?
- Perception
- Interpretation of sensory information
- Meaningful motor response
What is the function of the right parietal lobe?
Visuospatial functions
What are some of the functions of the frontal lobe?
- Motor function
- Problem solving
- Memory
- Language
Where is Broca’s area and what is it’s function?
- Found in the inferior frontal Gyrus
- Important for language production and comprehension
What are some of the contents of the temporal lobe?
- Primary auditory cortex
- Hippocampus
- Amygdala
- Wernicke’s area
Where is Wernicke’s area and what is it’s function?
- Located in the superior temporal Gyrus of the left hemisphere
- Concerned with understanding spoken word
What are some of the functions of the temporal lobe?
- Short term memory
- Equilibrium
- Emotion
What is the location and function of the occipital lobe?
- Located at the posterior aspect of the brain
- Contains the primary visual and visual association cortex
What is the function of the limbic system?
- Emotions
- Memories
- Arousal
Name 2 systems what the limbic systems influences
- Endocrine system
- Autonomic nervous system
What are the components of the limbic system?
The hippocampus, fornix and amygdala
What are the two layers of the dura?
The outer endosteal layer and the inner meningeal layer
Where does the outer endosteal layer line?
- The interior of the skull
- Adheres to and sends blood vessels and fibrous processes into the cranial bones
Where does the inner meningeal layer line?
Envelopes the CNS
What is the falx cerebri?
A small sickle-shaped reflection of the dura separating the two lobes of the cerebellum
What is the superior sagittal sinus?
Where the falx cerebri attaches to the cranium
Where is the inferior sagittal sinus?
At the free border of the falx cerebri
What are the subarachnoid cisterns?
Spaces caused by openings in subarachnoid space
What are the features of the blood- brain barrier which makes it protective?
- Edges of adjacent endothelial cells are bonded by tight junctions
- Basement membrane of CNS blood vessels lack fenestrations
- Pericytes which regulate blood flow, immunity and vascular permeability
- Astrocytes for control of blood-brain barrier & axon guidance/support
Where do arteries and veins lie in the brain?
Within the subarachnoid
What are the components of the blood-brain barrier?
- Endothelial cells of the capillaries
- Basement membrane (formed of true basement membrane and the pia)
- The astrocytic end-feet themselves
How does arterial blood arrive at the brain?
By the internal carotid (20%) and the vertebral arteries (80%)
Where does the internal carotid artery arise?
At the division of the common carotid artery
What does the internal carotid artery divide into?
It’s terminal branches, the anterior and middle cerebral arteries
What is the function of the anterior communicating artery?
Connects the anterior cerebral arteries and gives anterior perforating branches
What is the function of the posterior communicating artery?
Connects the internal carotid and vertebra-basilar systems via the posterior cerebral artery
Where does the anterior cerebral artery supply?
The top strip of the brain
Where does the middle cerebral arteries supply?
Around the sides of the brain
Where does the posterior cerebral artery supply?
The bottom of the brain
Which artery goes through the carotid canal in the skull?
The internal carotid artery
Which vein goes through the jugular foramen in the brain?
The internal jugular vein
Which arteries come through the foramen magnum in the brain?
Vertebral arteries
What is anastomosis?
A connection made between 2 channels of the body
How does venous blood drain in the brain?
- Drain into Dural venous sinuses
- Then back into the heart
Where are the Dural venous sinuses formed?
Between the two layers of dura matter
Where do internal cerebral arteries run?
Within the substance of the brain tissue and end when they reach the surface of the brain where they become external cerebral veins
Where do external cerebral veins run?
On the surface of the brain, crossing the subarachnoid space to drain into the Dural venous sinuses
What is the difference between Dural venous sinuses and veins?
Dural venous sinuses have no valves & no adventitia/media
What is the function of internal jugular veins?
Collects blood from the brain & superficial parts of the face/neck
What is the function of the tentorium cerebelli?
Divides the cerebellum and inferior part of occipital lobes
What are the 5 cranial nerves and the artery which runs through the cavernous sinus?
- Oculomotor nerve
- Trochlear nerve
- Abducens nerve
- Ophthalmic nerve
- Maxillary nerve
- Internal carotid artery
What is the significance of emissary veins?
They are a possible route for infection and inflammation
What is the function of arachnoid granulations?
Allow CSF to flow into the venous system
What is a choroid plexus?
A group of cells which produce CSF
What are ventricles in the brain?
The central space from within the hollow neural tube
How is close control over the volume and composition of the CSF done?
Tight junctions in the ventricles prevent fluid passage
What is ependyma?
A thin membrane of glial cells lining ventricles of the brain
Is the pre-central Gyrus motor or sensory?
Motor
Is the post-central Gyrus motor or sensory?
Sensory
