Anatomy-Theory Flashcards
The outer material of bones is different to the inner material, what are each called and how are they different?
. Outer cortex - dense, strong, heavy, compacted
. Inner medulla - porous, lightweight, weaker
What is the name of the bone within the medulla?
Trabecular/cancellous bone
How does cancellous bone compensate for weaker areas?
The structure is organised with more “struts” in areas where more pressure is applied
Where are the areas where bone marrow is likely to be found?
- Hip bone
- Sternum
- Ribs
- Vertebrae
- Cancellous regions of the femur and humerus
What is the function of bone marrow?
To produce red and white blood cells
What is the periosteum?
A dense envelope of connective tissue which surrounds bones, yet avoids joints and tendon articulations
During a fracture, why is the periosteum responsible for much of the pain?
It is well vascularised and innervated (also contains lymph vessels - but these don’t contribute to pain)
Where do nutrient vessels enter the periosteum?
Near the middle of the bone These vessels them ramify and continue through the inner medulla
Describe the process of endochondral ossification
Process by which a small hyaline cartilage piece grows and ossifies into bone. A capillary bud initiates the ossification by creating the primary ossification centre and entering the bone
How many primary ossification centres do long bones have?
1
What are the 4 different parts of a long bone?
Epiphysis - rounded end Epiphyseal growth plate - hyaline cartilage plate between metaphysis and epiphysis Metaphysis - part of growth plate leding to epiphysis Diaphysis - middle section of bone
What are the 5 different classifications of bone?
- Long bones - long and hollow
- Flat bones - protective
- Irregular bones - strangely shaped
- Sesamoid bones - present within tendons
- Shorts bones - cuboid shapes
How do fractures heal?
Weak collagen, cartilage and bony material - collectively called callus - surrounds the fracture The callus proceeds to remodel the bone to a normal shape
In what ways can a bone’s shape be influenced?
- Functional - due to genetics
- Adjacent structures apply a force
- Bone must grow around another structure
What is a tubercle?
A bump/small rounded area
What is a condyle?
A large rounded surface at the end of some bones
What is a fossa?
A small depression or hole
Which three fossae are present in the neurocranium?
- Anterior cranial
- Middle cranial
- Posterior cranial
What are foramina?
Holes for cranial nerves and blood vessels to pass through
What is the axial part of the skeleton?
The central skeleton
What is the appendicular skeleton?
Comprised of offshoots from the axial skeleton such as arms/legs/pelvic/pectoral girdles
What are Le Fort fractures?
There are three types and all involve different sections of the facial skeleton coming separated from the main skull
How many bones make up the vertebral column?
33
What are the five different categories of bones in the vertebral column and how many bones are in each category?
Cervical - 7 (C1-C7) Thoracic - 12 (T1-T12) Lumbar - 5 (L1-L5) Sacral - 5 (fused together) Coccygeal - 4 (fused together, forming coccyx)
What is the distinction between primary and secondary curves of the spine?
There are 4 curve - 2 point outwards, 2 point inwards Primary point out Secondary point in
Within a vertebral body, what is the function of the vertebral arch?
To protect spinal cord Formed of 2 x lamina and 2 x pedicle
What can emerge from an intervertebral formamen?
Spinal nerves
Where do facet joints form?
Between two articular processes of two adjacent vertebral bodies
All cervical vertebrae have ___ transverse foraminae for allowing passage of _________ ________
Two
Vertebral
Arteries
Why is C1 (atlas) unique?
It has no body or spinous process Instead it has posterior and anterior arches
Why is C2 (axis) unique?
It has an odontoid process (dens) which articulates with C1 and allows for head rotation
Why is C7 (vertebrae prominens) special?
It is (usually) the first spinous process that can be palpated
How many pairs of ribs exist?
12
What are the three categories of ribs?
- True ribs - articulate directly to sternum
- False ribs - articulate to sternum via coastal cartilage
- Floating ribs - do not articulate to sternum
Which ribs are the true ribs?
Pairs 1-7
Which ribs are the false ribs?
Pairs 8-10
Which ribs are the floating ribs?
Pairs 11-12
Why is rib 1 less likely to fracture?
It is protected by the sternum
What composes the pectoral girdle?
2 scapulae, 2 clavicles
What composes the pelvic girdle
2 hip bones and the sacrum
What is the most proximal bone in the arm?
Humerus
What are the names of the two more distal bones in the arm?
Radius (more lateral) and ulna (more medial)
What three types of bones make up the hand?
Carpals, metacarpals, phalanges
What is the largest bone in the leg?
Femur
What are the two long bones in the lower leg?
Tibia (more medial) and fibula (more lateral)
What three types of bones make up the foot?
Tarsals, metatarsals and phalanges
What are four functions of bone?
- Support and protection
- Calcium metabolism
- Red blood cell formation
- Provides and area for skeletal muscle attachment
What are three functions for cartilage?
- Flexibility
- Shock absorber
- Provide motility in joints where it is required
What is the name of the joint between the clavicle and the acromium process of the scapula?
Acromioclavicular joint
What are the three classes of joints?
- Fibrous
- Cartilaginous
- Synovial
Fibrous joints have the primary function of _________
Stability
There are two types of fibrous joint, what are they?
- Syndesmoses
- Sutures
What are syndesmoses?
Fibrous joints
Unites bones with a fibrous sheet such as the interosseous membrane between the fubula and tibia
What are sutures?
Fibrous joints
Found between bones in the skull
During infancy, what are in place of sutures in the skull?
Fontanelles
Soft and membranous wide sutures
There are anterior, posterior and lateral fontanelles and allow the bones to slide over eachother during birth
What are cartilaginous joints?
These are joints with a balance between stability and mobility
They are composed of cartilage
What are cells of cartilage called?
Chondrocytes
What are the two types of cartilaginous joint called?
- Primary - synchondroses - growth plates
- Secondary - symphyses
What are synchondroses?
Primary cartilaginous joints
Consist of a plate of hyaline cartilage allowing for bone growth by ossification
What are symphyses?
Secondary cartilaginous joints
Very strong and act as cushioning
They are fibrocartilage - a hybrid of firbrous and cartilaginous tissue
What is the inside of a intervertebral disc called?
Nucleus pulposus
What is the outside of the intervertebral disc called?
Annulus fibrosus
Why can a slipped disc cause pain in the legs?
Herniation of the disc may occur, which involves fluid contacting the spinal nerves causing leg pain
Where are synovial joints present?
Where two or more bones come together
How is a synovial joint structures around bone?
The joint will encapsulate bone from each side which forms a central joint cavity that contains synovial fluid for cushioning
What are bursae?
Fluid filled sacs around synovial joints that reduce friction
What are the five types of synovial joints?
- Pivot
- Balla and socket
- Plane (uniaxial)
- Hinge
- Biaxial
What are the two types of biaxial synovial joint?
. Saddle - i.e. between trpezium and metacarpal I
. Condylar - i.e. between metacarpal and phalangeal joints
. Condylar - oval surface articulating within a concave surface prevents full ball and socket type movement
Of the three main joint types which is the most stable and which has highest motility?
Most stable - Fibrous
Most mobile - Synovial
What is a slipped disc?
Articular surfaces are still in their normal anatomical relationship
What is subluxation?
There is recuced contact area between articular surfaces and they are slightly out of position
What is a dislocation?
There is complete loss of contact between articular surfaces - the bones are completely out of position
What type of joint is the temporomandibular joint?
Synovial
The temporomandibular joint is an articulation between the _________ ______ and the _________ ________ (of the temporal bone) with the head of the _________ ________ of the mandible
Mandibular fossa
Articular tubercle
Condylar process
What are the three different types of muscle?
- Cardiac
- Smooth
- Skeletal
Skeletal muscle is made up of many __________ which are made up of many muscle fibres which are made up of ____________ which are composed of _______ and _________ fibres within functionla units called ___________
Fascicles
Myofibrils
Actin and myosin
Sarcomeres
What is the difference between a sprain and a strain?
Muscles strain - think straining to lift a weight
Ligaments sprain - think sprained ankle - ankle has lots of ligaments and little muscle
In order to make a joint move, a muscle must do what?
Attach before and after the joint
What attaches muscle to bone?
Tendons
In releation to a muscle what are its “origin” and “insertion”?
Origin - this is where the beginning of the muscle attaches on one side of the joint
Insertion - this is where the end of the muscle will attach on the other side of the joint
What is an aponeurosis?
A flat tendon
(generally articulates with flat muscles and attaches to soft tissue rather than bone)
What movements does the deltoid muscle allow for?
- Extension of shoulder - posterior fibres
- Abduction of shoulder - middle fibres
- Flexion of shoulder - anterior fibres
The shallow socket of the glenoid fossa allows for what of the shoulder?
Circumduction
What are reflexes?
Involuntary protective actions mediated by the nervous system
What are the two main reflexes in relation to skeletal muscles
. Stretch reflex
. Flexion withdrawal
Describe the reflex responsible for protecting against overstretching
Stretch reflex
Stretch to muscle by action on tendon causing contraction
The reflex arc will bypass the brain
What is paralysis?
A muscle without a functioning motor nerve - muscle has reduced tone
What is spasticity?
Motor nerve is intact, descending controls from brain do not function so inhibitory factors are gone meaning the muscle has increased reflex action that is not filtered or controlled
What is atrophy?
Muscle wastage
Myocytes become smaller reducing muscle bulk and strength
Why is hypertrophy?
Muscle enlargement
Myocytes increase in size
What is hyperplasia?
Increase in the number of cells
What is hypoplasia?
Decrease in the number of cells
In what layer of tissue are skeletal muscles found?
Deep fascia
What is a septum?
A partion separating two compartments
How many compartments are in:
The thigh
The leg (calf)
Arm
Forearm
The thigh - 3
The leg (calf) - 3
Arm - 2
Forearm - 2
What is compartment syndrome?
Pressure can build within fascia formed compartments due to haemorrhage or fluid build up
This can affect the functioning of the muscles/nerves sue to pressure
The condition can be acute or chronic
What is the treatment for compartment syndrome?
Fasciotomy
Fascia is cut to relieve tension
What two components make up mucosa?
Epithelium and lamina propria
The upper and lower GI tract is separated by what?
Ileocecal junction
Which joint is most involved in chewing?
Temporomandibular joint
What is the collective name for the muscles involved in chewing?
Muscles of mastication
Which muscles are in control of closing the mouth?
Temporalis, masseter and medial pterygoid
Opening the mouth is controlled by which muscle?
Lateral pterygoid
What is the name of the circular muscle surrounding the mouth?
Orbicularis oris
What are gingivae?
The area of the gums
What are papilla?
Finger-like projections on the surface of the tongue
What are the four types of papillae?
- Foliate - edges of tongue (taste)
- Vallate - large lumps to the back (taste)
- Fungiform - visible all over (taste)
- Filiform - very small (touch and temperature)
Which two classes of muscle is the tongue made up of?
- Extrinsic - attaches tongue to skeleton to move it around during speech, swallowing and mastication (four pairs)
- Intrinsic - allows the shape of the tongue to be changed (four pairs)
What is the main muscle associated with the cheek?
Buccinator
What are the 4 types of teeth present at adulthood?
- Incisors
- Canines
- Premolars
- Molars (includes wisdom teeth)
How many teeth are present in adulthood?
32
What are the three main types of salivary glands?
- Parotid
- Submandibular
- Sublingual
Where does the parotid gland secrete saliva into the mouth?
By the upper second molar
Where does the sublingual gland secrete saliva?
In the floor of the mouth
(saliva is secreted superiorly)
Where does the submandibular glands secrete saliva?
Base of the tongue at the point where the tongue joins the mouth floor
What three parts of the pharynx split?
- Nasopharynx - posterior to nasal cavity
- Oropharynx - posterior to oral cavity
- Laryngopharynx - posterior to larynx
What do Tonsils produce?
White blood cells
The pharynx is composed of which three constrictor muscles?
- Superior pharyngeal
- Middle pharngeal
- Inferior pharyngeal
(their purpose is to push food inferiorly towards the oesophagus)
Why is the larynx raised during aspiration?
To prevent the aspiration of food or unwanted material.
It move the laryngeal outlet away from the passage of food and the epiglottis will close the inlet
Where is the oesophagus located in relation to the trachea?
Posterior
The oesophagus pierces the diaphragm at which verebral level?
T10
What is the peritoneum?
A serous membrane which can secrete lubricating peritoneal fluid that forms the lining of the abdominal cavity
What are thw two types of peritoneum?
- Visceral
- Parietal
What is peritonitis?
Inflammation of the peritoneum
What is abdominal guarding?
A defence mechanism by which the muscles of the abdomen involuntarily contracts to provide organ protection
The stomach will pass its contents through the _________ into the small intestine
Duodenum
How is the small intestine joined to the body wall?
Via the mesentary
What are the three parts of the small intestine?
- Duodenum
- Jejunum
- Ileum
What is the mesentary?
A double fold in the peritoneum involved in connecting intraperitoneal organs to the body wall
The space it creates between the folds allows for passage of neurovasculature
What are the three main functions of the large intestine?
- Transit
- Reabsorption of water and electrolytes
- Stool formation
What are the 5 different areas to the large intestine?
- Caecum
- Ascending colon (retroperitoneal)
- Transverse colon (intraperitoneal)
- Descending colon (retroperitoneal)
- Sigmoid colon (intraperitoneal)
The functions of the rectum and anus?
Stool formation
Waste excretion
Control of defecation is conferred by what?
Anal sphincter
(voluntary control)
What is the name given to the process that moves contents distally in the GI tract?
Peristalsis
There are two types of muscle in the walls of the GI tract - these are?
. Longitudinal (outer layer) - shortens the tube
. Circular (inner layer) - constricts the diameter
In the stomach which type of mucosa exists?
Secretory mucosa
Sphincter muscles have what function?
Control flow of substances
(through the GI tract)
Where is the cricopharyngeal sphincter muscle located?
Between the laryngopharynx and oesophagus - it prevents regurgitation
What is the name of the sphincter muscle between the stomach and duodenum called?
Pyloric sphincter
What are the names of the two sphincter muscles near the anus?
- Internal sphincter
- External (anal) sphincter
The abdominal organs are split into three parts, what are these three parts?
- Foregut - oesophagus to mid-duodenum
- Midgut - mid-duodenum to proximal 2/3rd of transverse colon - contains half of pancreas
- Hindgut - distal 1/3rd of transverse colon to proximal 1/2 of anal canal - includes other half of the pancreas
The foregut, midgut and hindgut regions are each supplied by which branches of the ascnding aorta?
Foregut - splenic vein
Midgut - superior mesenteric vein
Hindgut - inferor mesenteric vein via splenic vein
The foregut, midgut and hind gut are each drain by different veins, what are these?
Foregut - splenic vein
Midgut - superior mesenteric vein
Hindgut - inferior mesenteric vein via splenic vein
The splenic and superior/inferior mesenteric arteries drain into which vein?
Hepatic portal vein
Hepatic veins in the liver drain into which vein?
Inferior Vena Cava
What are the two venous systems in the body?
Portal system - drains absorptive organs (associated with the liver via the HPV)
Systemic system - drains all body organs (includes blood from liver)
Where do foregut structures drain lymph?
Via nodes along the splenic artery towards coeliac nodes around the origin of the coeliac trunk
Where do midgut structures drain lymph?
Via nodes located along the superior mesenteric artery towards superior mesenteric nodes located around the origin of the superior mesenteric artery
Where do hindgut structures drain lymph?
Via nodes located along the inferior mesenteric artery towards the inferior mesenteric nodes which are located around the origin of the inferior mesenteric artery
Obstruction of the GI tract can be caused by which two factors?
External - compress the wall of the tract
Internal - obstruct the lumen e.g. tumour, foreign body etc
How does the GI tract respond to a blockage?
The action of peristalsis is increased
What are collections of nerve cell bodies called in the CNS and PNS respectively?
Nucleus
Ganglion
What are bundles of axons termed in the CNS and PNS respectively?
Tracts
Nerves
What are afferent neurones?
Sensory neurones that bring signal towards the CNS
What is the somatic nervous system?
The nervous system of the external environment (out with organs) and the body wall
What is the automonic nervous system?
The nervous system associated with the interal environment of organs
It is composed of sympathetic and parasympathetic divisions
What are the four lobes of the brain?
- Frontal
- Parietal
- Occipital
- Temporal
What are gyri and sulci?
The outmost layer of brain tissue - the cerebral neocortex - is covered in lumps (gyri) and crevices (sulci)
The cerebellum is associated with which aspects?
Motor control and coordination
What are the three fossae of the cranial cavity floor?
- Anterior
- Middle
- Posterior
The brainstem exits through which foramen in the cranial cavity floor?
Foramen magnum
What is the role of the midbrain?
Vision and hearing
What is the general function of the medulla oblongata?
To aid vital function
The spinal cord extends down to which vertebral level?
L2
What is the tip of the spinal cord called?
Conus medullaris
Nerves exit the conus medullaris inferiorly through filmants called what?
Cauda equina
How many pairs of bilateral spinal nerves will exit the spinal cord?
31
What are the name of the two enlargements in the spinal cord and where are they located
Cervical enlargement - cervical region
Lubosacral enlargement - at the transition between the lumbar and sacral regions
Why are the two enlargements in the spinal cord required?
To accomodate extra neurones for the limbs
Where is white and grey hatter found in the brain?
White matter - inner area (contains myelinated axons)
Grey matter - outer area (full of cell bodies)
Where is white and grey matter found in the spinal cord?
White - outside
Grey - inside
What is the dorsal horn of a spinal nerve?
The is where sensory neurones come into the spinal cord
What is the ventral horn of a spinal nerve?
The area where motor cell bodies exist to send signals ut of the cord.
How are nerves composed?
Myelinated/non-myelinated fibres will group together and become surrounded by endoneurium
Perineurium groups many endoneurium groups together
Many perineurium strands are grouped together with fibrofatty tissue and blood vessels into an epineurium
What is the name of cranial nerve 1?
The olfactory nerve
The olfactory nerve (CN I) has which types of functionality?
Sensory
It contains sensory fibres related to smell
What is the name of cranial nerve 2?
The optic nerve
The optic nerve (CN II) has what functionality?
Sensory
Transmits visual information from the retina via sensory fibres
What is the name of cranial nerve 3?
Oculumotor nerve
The oculomotor nerve (CN III) has what functionality?
Motor
Involved in innervating muscles that aid eye movement, eyelid movement, pupil dilation and accomodation (focussing)
What is the name of cranial nerve 4?
Trochlear nerve
What is the functionalty of the trochlear nerve (CN IV)?
Motor
Innervates the superior oblique muscle in the eye
What is the name of cranial nerve 5?
Trigeminal nerve
The trigeminal nerve (CN V) has what functionality?
Sensory and motor
It allows for sensation in the face and motor functions such as biting and chewing
It has 3 divisions:
V1 - the ophthalmic nerve (sensory)
V2 - the maxillary nerve (sensory)
V3 - the mandibular nerve (sensory and motor)
What is the name of cranial nerve 6?
Abducent nerve
What is the functionality of the abducent nerve (CN VI)?
Motor
Controls the lateral rectus muscle in the eye
What is the name of cranial nerve 7?
Facial nerve
What is the functionality of the facial nerve (CN VII)?
Sensory and motor
Controls muscles of facial expression and transports taste signals from the anterior 2/3rd of the tongue
What is the name of cranial nerve 8?
Vestibulocochlear nerve
What is the functionality of the vestibulocochlear nerve (CN VIII)?
Sensory
Transports sound and balance information to the brain
What is the name of cranial nerve 9?
Glosspharyngeal nerve
What is the functionality of the glossopharyneal nerve (CN IX)?
Sensory and motor
Carries general sensory information from the skin of the external ear, internal surface of the tympanic membrane, the walls of the upper pharynx, and the posterior one-third of the tongue.
Parasympathetic component of the glossopharyngeal nerve innervates the ipsilateral parotid gland
What is the name of cranial nerve 10?
Vagus nerve
What is the functionality of the vagus nerve (CN X)?
Sensory and motor
Responsible for parasympathetic control of the heart, lungs, and digestive tract as well as other organs
It also innervates some skeletal muscle in the body
What is the name of cranial nerve 11?
Spinal accessory nerve
What is the functionality of the spinal accessory nerve (CN XI)?
Motor
Supplies sternocleidomastoid and trapezius muscles
What is the name of cranial nerve 12?
Hypoglossal nerve
What is the functionality of the hypoglossal nerve nerve (CN XII)
Motor
Innervates all extrinsic and intrinsic muscles of the tongue except for the palatoglossus
What are foramina?
Areas where cranial nerves will exit the brain and pass out through the skull
What two components come together to form a spinal nerve?
- The posterior rootlets of the dorsal horn
- The anterior rootlets of the ventral horn
Where do spinal nerves lie?
In the intervertebral foramen
This is the space formed between two vertebrae which articulate together
What is the general type of functionality of any spinal nerve?
Sensory and motor
What happens to a spinal nerve when it leaves the intervertebral foramen?
It will split into anterior and posterior rami (both of which are mixed nerves)
How many vertebrae are there?
33
How many spinal nerves are there?
31
How many spinal nerves comes from each region of the spinal cord?
. Cervical - 8
. Thoracic - 12
. Lumbar - 5
. Sacral - 5
There is also one coccygeal spinal nerve
If there are only 7 cervical vertebrae, how are there 8 associated spinal nerves?
Initially, each spinal nerve arises above the vertebra it is names after
The the thoracic region the spianl nerves are then names after the vertebra below
This means there is a space for the 8th cervical spinal nerve above T1 vertebra
What is a dermatome?
An area of skin supplied by one sensory axon of a spinal nerve fibre only
This will generally correspond to axial segments along the body length
Nerve plexuses are only formed by _______ rami
Anterior
What is a plexus?
An intertwining of anterior rami
Name some nerve plexuses in the body
Cervical - C1-C4 anterior rami
Brachial - C5-T1 anterior rami
Lumbar - L1-L4 anterior rami
Sacral - L5-S4 anterior rami
Where does the sypathetic nerve outflow arise between?
T1 and L2
Why does sympathetic outflow arise between T1 and L2?
These vertebrae have an additional horn - the lateral horn
This allows sympathetic axons to leave the spinal cord via ventral rootlets
How do parasympathetic axons leave the CNS?
Cranial nerves III, VII, IX and X
Sacral spainal nerves (craniosacral outflow)
The body wall is innervated by which types of neurones?
Somatic sensory
Somatic motor
Organs have which types of innervation?
Visceral afferent (sensory)
Sympathetic/parasympathetic (motor)
What are the two functional divisions of the nervous system?
Somatic nervous system - body wall
Autonomic nervous system - internal environment
What are nociceptors?
Receptors for pain
The somatic pathway for touch is a three neurone chain, describe it
- First order neurone - delivers impulse form body wall to dorsal horn
- Second order neurone - depending on sensation, the impulse will cross the spinal cord at different levels. Second order neurones run up the spinal cordand synpase again at the thalamus
- Third oder neurone - travels to appropriate area of the cortex based on repose from thalamus
What is a dermatome?
An area of skin, usually an axial segment, supplied by one spinal nerve
The associated dematome of T10 is at what level on the body
Area of umbilicus
What are the four lobes of the cerebrum?
- Occipital
- Temporal
- Parietal
- Frontal
Which two parts compose the somatic motor pathway?
Upper motor neurone
Lower motor neurone
How does the motor pathway result in skeletal muscle movement?
. Voluntary intentions begin in the primary somatomotor cortex
. The action potential reaches the ventral horn of the spinal cord via the upper motor neurone
. The upper motor neurone then synapses with the lower motor neurone
. The AP continues along axons to reach the spinal nerve and continues to the anterior ramus
. The impulse continues through a plexus and finally the neuromuscular junction is reached for the specific muscle
Describe paralysis
The muscle is without a functioning lower motor neurone
The muscle has reduced tone and cannot contract
It is caused by a lower motor neurone lesion
Describe spasticity
Occurs due to an upper motor neurone lesion
Inhibitory signals can no longer be sent to calm down reflexes and the muscle will therefore have increased tone
Sympathetic nerves leave the spinal cord between which vertebrae?
T1 to L2
This is the thoracolumbar outflow
In the sympathetic nervous system, there is a two neurone chain, what are these two neurones?
Preganglionic
Postganglionic
The preganglionic nerone leaves the spinal cord via which area?
Ventral horn
Splanchnic nerve supply what?
Visceral organs
Where do parasympathetic ganglia lie?
On the organ wall
All parasympathetic axons leave the CNS by which cranial nerves?
. CN III - oculomotor nerve
. CN VII - facial nerve
. CN IX - glossopharyngeal nerve
. CN X - vagus nerve
What is the only instance of a one-neurone chain?
The adrenal gland is innervated solely by a preganglionic sympathetic nerve.
It will release secretions (adrenaline) directly into the bloodstream
The vagus nerve supplies which areas of the body?
Neck
Chest
Abdomen
Mid-gut
The sacral spinal nerves carry sympathetic innervation to which body areas?
Hindgut
Pelvis
Perineum
What are the male and female gametes?
Male - spermatozoa
Female - Oocyte
What is the pelvic floor?
An internal wall of skeletal muscle separating the pelvic cavity from the perineum
Where is the perineum located in respect to the pelvic floor?
Inferiorly
(between proximal parts of lower limbs)
What are the three openings in the pelvic floor?
Distal alimentary tract
Renal tract
Reproductive tract
What forms the pelvic roof?
Formed from parietal peritoneum
What is the most inferior part of the peritoneal cavity?
Rectouterine pouch (of Douglas)
In females, where is the vesico-uterine pouch located?
Between the bladder and uterus
What are the three layers to the uterus wall?
Perimetrium (outermost)
Myometrium
Endometrium (innermost)
What moves the ovum along the uterine tubes?
Cilia
What is the role of fimbriae?
To gather the ovum into the infundibulum of the uterine tube
Where does fertilisation occur?
Ampulla
What is an ectopic pregnancy?
When the fertilised ovum implants outwith the uterine cavity
This can be an emergency due to the risk of haemorrhage
(tubal pregnancies at much more common than abdominal)
How can female sterilisation be brought about?
Tubal ligation
. Both uterine tubes are clipped or cut
. The lumen is blocked and the ovum has no passage to the uterus
What is the anatomical position of the penis?
Erect
What is the tube that sperm pass through?
Vas deferens
How long do sperm take to mature?
64 days
What is the epididymis?
The transition from the testis to the vas deferens
What is the function of the dartos muscle?
Lies in superficial fascia to wrinkle/thicken scrotal skin to maintain correct scrotal temperature
What is present in the spermatic cord?
Vas deferens
Testicular artery
Pampiniform plexus
How does torsion of the testis occur?
Twisting of spermatic cord
Blood supply is stopped and swelling follows
This causes severe pain and danger of testicular necrosis
Which glands contribute to semen?
Seminal and prostate
Erection and ejaculation are controlled by which branches of the ANS?
Erection - parasympathetic
Ejaculation - sympathetic
The spermatic cord reaches the pelvic cavity via which canal?
Inguinal canal
What is a vasectomy?
The cutting of the vas deferens
What are the two main divisions of the mediastinum?
- Superior
- Inferior
Inferior further divided into anterior, middle, posterior
Where is the heart located?
Middle medistinum
Which anatomical landmark signifies the border between the superior and inferior mediastinum?
Sternal angle
What is the pericardium?
Fibrous sac surrounding the heart and major vessels
How many layers is the pericardium comprised of and what are they?
2
Fibrous - tough and thick, prevents overfilling, protective
Serous - Thinner, membraneous, secretes serous fluid
Which condition involving the fibrous pericardium is very dangerous?
Haemopericardium
This is blood in the pericardial space leading to cardiac tamponade
The blood contributes to increased pressure compressing the heart
The serous pericardium is subdividied into which two layers?
Visceral - lines heart
Parietal - lines fibrous pericardium
What are the three layers of heart muscle?
Epicardium
Myocardium
Endocardium
What are the auricles of the heart?
Extensions of the atria
What are the four heart borders?
- Right - formed by right atrium
- Left - formed by left ventricle
- Superior - left and right atrium as well as great vessels
- Inferior - left and right ventricles
What does the inner fibrous cartilage skeleton of the heart allow for?
Structure to be mainatined
A electrical insulator between heart chambers
What are endocrine glands responsible for?
Manufacturing, storing and releasing hormones (into the bloodstream)
What makes up the diencephalon?
Hypothalamus and thalamus
(located superior to the brainstem)
What are the three components of the brain stem from superior to inferior?
- Midbrain
- Pons
- Medulla oblongata
What connects the anterior and posterior pituitary glands?
The infundibulum
Which hormones are secreted by the posterior pituitary gland?
- Oxytocin
- Vasopressin (ADH)
Which hormones can the anterior pituitary secrete?
FSH
LH
Growth hormone
Prolactin
TSH
Adrenocorticotrophic hormone
How do the stimulating hormones from the hypothalamus reach the anterior pituitary to allow it to produce hormones?
. Hormones from hypothalamus are secreted into first capillary bed
. They then travel to the hypophyseal portal veins
. Then to the second capillary bed
. They can then stimulate the anterior pituitary cells to produce its hormones
The thyroid gland is made up of which three parts?
- Isthmus
- Right lobe
- Left lobe
(there is also a fourth lobe - the pyramidal lobe)
The thyroid gland used what to manufacture which two hormones?
Iodine
- Triiodothyronine (T3) - regulates metabolism
- Thyroxine (T4) - regulates metabolis,
Where are the parathyroid glands located?
There are 4
Superior and inferior to either side of the cricoid cartilages
What is the role of the parathyroid glands?
To secrete parathyroid hormone
This controls the amount of calcium in blood and bone
Which arteries supply the thyroid gland?
Right thyroid artery - branch of right subclavian
Left thyroid artery - branch of left subclavian
Which veins drain the thyroid gland?
Superior, middle and inferior thyroid veins
The pancreas is a __________ organ
Retroperitoneal
Which arteries supply the pancreas?
Coeliac and superior mesenteric arteries
Which veins drain the pancreas?
Splenic and superior mesenteric veins
What are the two functionally distinct areas of the pancreas?
Endocrine - secretes hormones into blood
Exocrine - secretes digestive enzymes into duct system
The adrenal glands are directly superior to which organs?
Kidneys
What are the two functional areas of the adrenal glands?
- Arenal cortex
- Adrenal medulla
The adrenal cortex will produce which hormones?
- Glucocorticoids
- Mineralocorticoids - regulate salt balance and blood pressure
- Androgens - male sex hormones
The inner medulla of the adrenal gland will produce which hormones?
- Adrenaline
- Noradrenaline
Involved in the fight or flight response
The adrenal glands are supplied by which arteries?
- Superior suprarenal artery - originates from inferior phrenic artery
- Middle suprarenal artery - originates from aorta directly
- Inferior suprarenal artery - originates from renal arteries
What is the venous drainage pathway of the left adrenal gland?
Suprarenal vein, left renal vein, IVC
What is the venous drainage pathway for the right adrenal gland?
Right suprarenal vein directly to IVC
The testes secrete testosterone in response to which hormone?
LH
(from anterior pituitary)
The ovaries produce oestrogen and progesterone in response to which hormones?
LH and FSH
Which arteries supply the reproductive organs?
Gonadal arteries
(direct branches of IVC)
What is the venous drainage pathway for the right gonad?
Direct to IVC
What is the venous drainage pathway for the left gonad?
Left renal vein, then IVC
At which vertebral level does the aorta enter the abdominal cavity?
T12
At which vertebral level does the coeliac trunk come off of the aorta?
T12
At which vertebral level do the gonadal arteries come off of the aorta?
L2
At which vertebral level does the SMA come off the aorta?
L1
At which vertebral level does the IMA come off of the aorta?
L3
At which vertebral level does the aorta bifurcate to the common iiac arteries?
L4
At which vertebral level does the common iliac artery bifurcate?
L5
How do arteries often prevent overstretching?
Running in a tortuous course
Why are arteries located deep to veins?
To reduce haemorrhage and increase protection
Which “tone” is always present in arteries?
Sympathetic
Does the smooth muscle in artery walls have parasympathetic control?
No
Only vary degrees of sympathetic control - there a tonic conduction of sympathetic APs
At which vertebral level range is the sympathetic outflow?
T1 to L2
What is the angle of Louis?
This is the sternal angle
The point at which the start of the aortic arch cuts through axially to meet the end
The ascending aorta has 2 branches, what are these?
Right coronary artery
Left coronary artery
What are the 3 branches of the aortic arch?
Brachiocephalic trunk
Left common carotid artery
Left subclavian artery
The vertebral arteries arise from which arteries?
Right and left subclavian arteries
Where do the verebral arteries travel?
Through the transverse foraminae within cervical vertebrae
They enter the cranial cavity through the foramen magnum
What is the name given to the circular vessel formation in the brain formed by the anastomosis of the internal carotid areteries and vertebral arteries?
Circle of Willis
The left and right internal vertebral arteries converge together at the brainstem forming which artery?
Basilar artery
What is the function of the carotid sinus?
Blood pressure sensor
It is located at the carotid bifurcation
Baroreceptors at the carotid sinus are innervated by which cranial nerve?
CN IX
Glossopharyngeal nerve
(also innervates the carotid body to monitor blood/gas levels and pH)
What is the blood brain barrier?
Tight junctions between endothelial cells in the brain preventing leaky capillaries
What are the support cells that surround brain capillaries?
Astrocytes
Which sustances can diffuse throug the blood brain barrier?
Oxygen, glucose and carbon dioxide
In an anastomosis, what is each alterative route termed?
A collateral
What are end arteries?
End arteries occur when they ar the only artery supplying a certain region of the body
The aortic hiatus occurs at which vertebral level?
T12
At which vertebral level does the abdominal aorta bifrcate into the left and right common iliac arteries?
L4
Name the main peripheral pulses in the:
a) Neck
b) Upper limb
c) Lower limb
a) Carotid pulse
b) Brachial pulse, radial pulse
c) Femoral pulse, popliteal pulse, posterior tibial pulse, dorsalis pedis pulse
How can veins utilise the pulsatile properties of arteries to aid the movement of blood within them?
By wrapping aroud arteries forming plexuses
What are the two main venous systems?
- Hepatic portal system
- Systemic venous system
What is tissue fluid called once it enters the lymphatic system?
Lymph
Where is lymph returned to the venous system?
Left and right lymphatic ducts into the left and right venous angles of the subclavian veins in the neck
What is the only lymphatic vessel large enough to be found in dissection?
Thoracic duct
Generally, what are the main functions of the urinary tract?
. Blood pH control
. Water balance
. Electrolyte balance
. Blood pressure control
. Metabolism of waste products and drugs
. Stimulates red blood cell production - by action of erythropoietin hormone
. Absorption of calcium
Describe the pathway of urine through the body
- Kidneys
- Ureter
- Bladder
- Urethra
What is the epithelium of the urinary tract?
Transitional epithelium
(urothelium)
It has a stratified appearance with dome shaped cells allowing for stretching
It is present from the ureter to the proximal end of the the urethra
The distal end of the urethra has which type of epithelium?
Stratified squamous
The urinary tract is split into which two divisions?
- Upper - bilateral structures, kidneys, ureters
- Lower - midline structures, bladder, urethra
Where does the upper urinary tract begin and end?
Begins in abdomen with the kidneys and ureters
Ends at level of ileac crests at L4
Where does the lower urinary tract begin and end?
Begins at level of ileac crests
Ends at perineum
What can protect the kidneys?
. Being retroperitoneal
. Ribs 11 and 12
. Skeletal muscles of back, anterolater and posterior walls (guarding)
. Renal fascia, para and perinephric far and the renal capsule
At which vertebral level is each kidney situnated?
Right - L1-L3
Left - T12 and L2
What do the renal hilum structures include?
- Renal vein
- Renal artery
- Ureter
Which arteries supply the kidneys and what are these arteries branches of?
Renal arteries
(branches of aorta)
Which renal artery is longer and why?
Right renal artery
The vena cava is beside the right kidney, so the right renal artery must go past it
What are the three paired bilateral branches of the aorta?
- Adrenal arteries
- Renal arteries
- Gonadal arteries
How many segments make up a kidney?
5 segments
Which vein will drain into the left renal vein?
Left gonadal vein
What are the two main layers of the kidney called?
- Renal cortex (outer)
- Renal medulla (inner)
What is the name given to the apex of the renal pyramids?
Papilla
What is the name given to the first section of a nephron, and what composes this section?
Renal corpuscle
(Bowman’s capsule and glomerulus)
Describe the passage of urine through the kidney
1.Nephron collecting ducts
2. Renal papillae
3. Minor calyx
4. Major calyx
5. Renal pelvis
6. Ureter
Kidney stones are formed by what?
Calcium salts
What is the first area of potential obstruction in the kidney?
Pelviuteric junction
What are the second and third areas of constriction to the ureter?
. When ureter crosses the anterior aspect of the external iliac artery
. Ureteric orifice - opening between ureter and bladder
What is the name of pain given to that of the kidneys caused by obstruction?
Renal colic
What are the three points of entry/exit to the bladder?
Ureteric orifices
2 superior (from kidney ureters)
1 inferior passes into urethra
What are the muscles that act as sphincters at the ureteric orifices?
Detrusor muscles
The external urethral sphincter allows for what?
Voluntary control of micturition
What is the term given to the process by which a prostate gland will gradually increase in size with age?
Benign prostatic hyperplasia
(gradually compresses urethra)
What are the two types of catheterisation in relation to the urinary tract in males specifically?
- Suprapubic - inserted above public symphysis
- Urinary - through urethra, prostatic urethra and into the bladder
Give the 3 main characteristic of the female urethra
- It is shorter than in males
- It is distensible - due to elastic tissue in its walls
- It opens into the vestibule - opening with external environment
What are the consequences of the properties of the female urethr when compared to males?
. Easier to catheterise
. More commonly encounter UTI
At which point does the upper respiratory tract become the lower?
Vertebral level C6
At the junction between the larynx and trachea
How many lobar bronchi are within each lung
There is only for each lung lobe
Right - 3
Left - 2
How many segmental bronchi are there?
10
Each supplies a bronchopulmonary segment
Each lung lobe is separated by what?
Fissure
Why can pronchopulmonary segments be easily removed by surgeons?
They have their own segmental bronchi, blood supply, lymphatics and nerve supplies
This means their removal does not impact the rest of thelung as much as it otherwise would
What is the epithelium of the lower respiratory tract?
Respiratory epithelium
(goblet cells and ciliated cells)
What is the mucociliary escalator?
The process by which mucous is constantly produced by goblet cells and projected up and out of the respiratory tract by cilia
Cilia and their function are affected by which 3 main factors?
- Temperature (cool environments specifically)
- Drying of the mucosa
- Toxins - such as cigarette smoke
Hyaline cartilage is present in the trachea until when?
Segmental bronchi
What separates the nasal cavities?
Nasal septum
(anterior cartilage and bony posterior section)
Which two bones make up the bony posterior section of the the nasal septum?
. Ethmoid bone (superior)
. Vomer bone (inferior)
Which four main types of cartilage make up the larynx?
. Thyroid
. Cricoid
. Epiglottis
. Arytenoid
What is the rima glottidis?
The space between vocal cords
(narrowest point)
What are the three interesting structures on the lateral wall of the nasal cavity?
The superior concha
The middle concha
The inferior concha
What is the purpose of the conchae in the nasal cavity?
They are shell shaped, increasing surface area, and allowing turbulent air flow which brings air in contact with walls
This allows air to be warmed and humidified
What is the purpose of tonsils?
To produce white blood cells
The pharynx contains which three parts?
- Nasopharynx
- Oropharynx
- Laryngopharynx
Which ribs connect directly to the sternum?
The true ribs
(ribs 1-7)
How do false ribs articulate with the sternum?
Ribs 8-10 join to the sternum via the costal cartilage
The head of the rib articulates with what?
Vertebral colum forming a costovertebral joint
The tubercle on the neck of a rib articulates with what?
Thoracic vertebra
What is the purpose of the costal groove on the body of the rib?
This houses the neurovascualr bundle
(intercostal nerve, artery and vein)
What are the four components of the sternum?
Manubrium
Sternal angle
Body
Xiphoid process
What is the name of the joint between ribs and vertebrae?
Costovertebral joints
What is the name of the joint between the sternum and costal cartilage?
Sternocostal joint
What is the name of the joint between a rib and costal cartilage?
Costochondral
What are the three anatomical planes?
- Sagittal
- Coronal
- Axial (transverse)
What are the posterior surfaces of the wrists, hand and tongue referred to as?
Dorsal surfaces
The anterior surface of the wrist is which type of surface?
Volar surface
The anterior surface of the tongue is called what?
Ventral surface
What does the term ipsilateral mean?
The structure is on the same side of the body to the structure to which it is being compared
What does contrelateral mean?
The structure lies on the opposite side to the structure to which it is being compared
What is circumduction?
Circular motion at a joint