Principles Anatomy Outcomes Flashcards
What is a joint?
A joint is an articulation between adjacent parts of the skeleton (i.e. bones and cartilage).
What does the presence of joints enable our skeleton to do?
Joints provide mobility and enable locomotion.
Name the three subcategories of fibrous joints, explain them, and give an example of each.
SYNDESMOSES: fibrous membranes uniting bones via fibrous sheets, e.g. = interosseous membrane between the tibia and fibula. They are partially movable.
SUTURES: joints between the bones of the skull, e.g. = coronal suture. They are highly stable.
FONTANELLES: wide sutures in the neonatal skull, e.g. = anterior, posterior, & lateral fontanelles. These allowing growing bones to “slide” over each other.
Name the TWO subcategories of cartilaginous joints, explain them, and give an example of each.
PRIMARY CARTILAGINOUS: synchondrosis- i.e. bones connected by hyaline cartilage. These may be temporary, e.g. EPIPHYSEAL GROWTH PLATE, which permits growth in bone length, when growth is complete it undergoes ossification & fusion. E.g. = between the epiphysis and diaphysis of long bones, between the occipital & the sphenoid.
SECONDARY CARTILAGINOUS: symphysis- i.e. 2 closely joined bones, forming either an immovable or completely fused joint. These are strong fibrocartilage. E.g. = invertebrate discs.
Nb: both types of joint can slip, primary-> slipped femoral epiphysis. Secondary-> slipped disc.
Name 3 features of a typical synovial joint.
Any 3 of:
- Two or more bones articulating with each other.
- Articulated surfaces are covered in hyaline ‘articular’ cartilage.
- A capsule wraps around the joint: a superficial, strong, fibrous layer & a deeper synovial membrane layer which secretes synovial fluid.
- Joint cavity: contains synovial fluid (cushioning, nourishing, lubricating).
- Supported by ligaments (fibrous bands from bone-bone-> strength and stability).
- Associated with skeletal muscles and their tendons (fibrous band from muscle-bone, which insert onto bones at either side of the joint).
- Associated with bursae (prevent friction), = extensions of joint cavity/closed sacs separate from the joint cavity.
- May have special features, e.g. articular disc of the TMJ.
What is meant by the term bursa?
A fluid filled sac/cavity at a joint which prevents friction..
What is meant by a slipped femoral epiphysis?
The femoral epiphysis remains in the hip socket, but the metaphysics moves in an anterior direction with external rotation.
Summarise the basic anatomy of an invertebral disc.
Outer ring of annulus fibrosus- a fibrous ring of fibrocartilage.
Inner soft nucleus pulposus - a soft centre, which is 90% water in newborns.
Each disc allows small amounts of movement in all direction, when combined this allows for considerable movement.
Describe what is meant by the term herniation/dislocation/ slipped disc.
It is the complete loss of contact between articular surfaces.
Describe what is meant by the term subluxation.
A reduced area of contact between articular surfaces.
What is meant by a torn ligament?
Ligament injury, but articular surfaces are still in their normal anatomical relations to each other.
Summarise the relative stability of the different joint types.
Fibrous is most stable, then cartilaginous, then synovial (least stable).
Summarise the relative mobility of the different joint types.
Synovial is most mobile, then cartilaginous, then fibrous (least mobile).
What is meant by the normal range of movement of a joint?
The full movement potential of a joint, usually its range of flexion and extension. Note: some patients may have natural or pathological hypermobility.
Define hypermobility of a joint.
The joint has a range of movement greater than that of the normal range of movement.
Name three joints which commonly dislocate.
Any 3 of:
- Temporomandibular
- Acromioclavicular
- Craniovertebral
- Shoulder
- Elbow
- Hip
- Pubic symphysis
- Interphalangeal (DIP & PIP)
- Knee
- Ankle
Describe the anatomy of the TMJ.
Right and left TMJ. The synovial articulations between the mandibular fossa, & the articular tubercle of the temporal bone SUPERIORLY, & the head of the condylar process of the mandible INFERIORLY.
What happens in a TMJ dislocation?
The head of the condylar process of the mandible becomes stuck anterior to the articular tubercle of the temporal bone. It may be unilateral or bilateral. Chin remaining in midline suggests bilateral.
Are joints well or poorly vascularised? What challenges does this present if the joint is dislocated?
Joints are well vascularised, and periarticular arterial anastomoses are common.
If the joint is dislocated, this may result in damage of these arteries, and compromise blood flow distal of the joint.
Which sensations are detected by the sensory receptors of joint nerves?
Pain, touch, temperature and proprioception.
Define endochondral ossification.
It is the process in which an initially small, hyaline cartilage version of a bone, grows, ossifies and subsequently becomes a bone.
Name the parts of a long bone.
Epiphysis, epiphyseal growth plate, metaphysis, and diaphysis.
What is an epiphyseal growth plate? Name an example.
Temporary hyaline cartilage, permits growth in bone length. When growth is complete it undergoes ossification & fusion. E.g. = between the epiphysis and diaphysis of long bones, between the occipital & the sphenoid.
What are the layers of bone? Describe each.
- Outer layer of compact cortical bone: which is dense, strong & heavy.
- Inner medulla of spongy/trabecullar bone: porous, weak & light.
- Central medullary cavity: may contain bone marrow. Red in hematopoeitic bones, and white/fatty marrow in non-blood cell forming bones.
Which structure covers bones? Describe it. Why does it hurt so much if torn, i.e. during fractures?
The periosteum. It is a dense layer of vascularised, fibrous & connective tissue enveloping the bones (except at joints).
It is well innervated with sensory nerves, and so can cause extreme pain.
List the stages of healing in a fracture.
Trauma may cause a bone to fracture.
- Initial healing: callus of new bone surrounds fracture line.
- Callus remodelling: the bone reassumes normal shape.
- Healed: the bone heals more or less in a normal shape.
What is meant by the term “surgical reduction and fixation”?
Reduction = restoring a fracture/dislocation to its correct alignment.
Fixation = the use of implants to stabilise a fractured bone, holding it in the correct alignment and thus promoting healing.
Define the term, “bony feature”.
Features found on the surfaces of bones.
They may be functional, i.e. suited for a particular function.
They may occur as a result gf an adjacent structure applying force to the developing bone, moulding its shape.
Or, if an adjacent structure is developing at the same time as the bone, then the bone has to grow around the other structure, forming a foramen.
Give two examples of bony features.
- Greater tubercle of the humerus
- Styloid process of the radius
- Ischial tuberosity
- Lesser trochanter
- Femoral condyle
- Tibial tuberosity
- Medial malleolus
- Cranial fossae
- Cranial foramina
What is a callus?
Rapidly proliferating osteoblasts which surround fractures, to unite the broken fragments.
Name the 3 cranial fossae.
Anterior, middle and posterior cranial fossae
What is the cranial foraminae?
A hole enabling cranial nerves and blood vessels to enter and exit the cranial cavity.
List the bones of the axial skeleton.
Bones of the skull, neck (including cervical vertebrae & hyoid bone), and trunk (chest, abdomen & back).
List the bones of the appendicular skeleton.
Bones of the: pectoral girdle (attaches upper limbs to axial skeleton), upper limbs, pelvic girdle (attaches lower limbs to axial skeleton), and the lower limbs.
Define cranial vault. Which bones is this composed of?
The bones of the neurocranium.
Sphenoid bones, frontal bones, temporal bones, parietal bones, occipital bone.
Which two sutures can be found in the neurocranium, and where?
The coronal suture, lies between the frontal bone and the parietal.
The sagittal suture, lies between the parietal bones.
State and identify the features shared by all cervical vertebrae.
All cervical vertebrae have a transverse process and transverse foramen.
What bones make up the facial skeleton?
The L&R nasal bones, the L&R zygomatic bones (form prominence of cheek), the maxilla, and the mandible.
What is a Le Fort Fracture?
Fractures of the midface, which involve separation of all, or a portion of the midface from the skull base.
Explain the three types of Le Fort Fractures.
Type 1: a floating palate.
Type 2: a floating maxilla
Type 3: a floating face.
Identify the bony features of the mandible.
The coronoid process. The condylar process. The ramus. The angle. The inferior border. The body. The mental foramen. The mental process.
Describe the vertebral column, or spine, in terms of regions.
Cervical region (C1-C7), Thoracic region (T1-T12), Lumbar region (L1-L5), Sacral region (5 sacral vertebra fused to form 1 sacrum), Coccygeal region (4 vertebra fused to form 1 coccyx).
Describe the vertebral column, or spine, in terms of curvatures.
How does this differ in a foetus?
The cervical region is a secondary curvature. Thoracic region is a primary curvature. The Lumbar region is a secondary curvature. The Sacral region is a primary curvature.
They are all primary curvatures in a foetus.
What features does a “typical vertebra” possess, and what are the functions of these features?
SPINOUS PROCESS: ligament and muscle attachments.
INFERIOR ARTICULAR PROCESS x2 and the SUPERIOR ARTICULAR PROCESS x2: provide mobility with adjacent vertebra via synovial facet joints.
The TRANSVERSE PROCESS x2: ligament, muscle and rib articulations.
VERTEBRAL FORAMEN: transmits, and protects the spinal cord.
VERTEBRAL BODY: weight bearing.
THE VERTEBRAL ARCH: consists of LAMINAx2 and PEDICLEx2, and is responsible for protecting the spinal cord.
What is an intervertebral disc?
A disc forming a fibrocartilaginous joint/symphysis to allow slight movement of the vertebrae, and acting as a ligament to hold the vertebrae together.
What are intervertebral foraminae? What is their purpose?
Foraminae existing between adjacent vertebrae, spinal nerves emerge through them.
What are thenames and unique features of C1, C2 and C7?
Define “pectoral girdle”, pelvic girdle” “arm”, “forearm”, “thigh” & “leg”
Compare & contrast the pattern of the bones of the upper and lower limbs
C1: ATLAS. It does not have a body or a spinous process, instead it has a posterior, and an anterior arch.
C2: AXIS. This has an odontoid process, which projects superiorly from the body.
C7: VERTEBRAE PROMINENS. This is usually the first palpable spinous process. It can be palpated in the midline of the posterior aspect of the neck.
What are the names and unique features of C1, C2 and C7?
C1: ATLAS. It does not have a body or a spinous process, instead it has a posterior, and an anterior arch.
C2: AXIS. This has an odontoid process, which projects superiorly from the body.
C7: VERTEBRAE PROMINENS. This is usually the first palpable spinous process. It can be palpated in the midline of the posterior aspect of the neck.
Define pectoral girdle.
It is the 2 scapulae, and the 2 clavicles.
Define pelvic girdle.
The 2 hip bones and the sacrum.
Define arm and forearm.
The arm is the bone between the elbow and shoulder joint, i.e. the humerus.
The forearm is the bones between the wrist and elbow joints, i.e. the radius and ulna.
Define “thigh” & “leg”.
Thigh: the bone between the hip and knee joint, i.e. the femur.
Leg: bones between the knee and ankle joints, i.e. the fibia and tibula.
Compare & contrast the pattern of the bones of the upper and lower limbs.
Upper limb: 1 long bone in the arm, i.e. the humerus. 2 long bones in the forearm, i.e. the radius and ulna. The hand, composed of the carpal bones (wrist), the metacarpals (palm), and the phalanges (fingers).
Lower limb: 1 long bone in the thigh, i.e. the femur. 2 long bones in the leg, i.e. the tibia and fibula. The foot, composed of the tarsal bones (hindfoot/midfoot), the metatarsals (forefoot), and the phalanges (forefoot-toes).
Where do arteries carry blood from, and to? Where do veins carry blood from, and to?
Arteries carry oxygenated blood from the heart, to the tissues and organs.
Veins carry deoxygenated blood from the tissues and organs, to the heart.
What is the cardiovascular system? Describe its components.
It is the arterial system + the heart + the venous system.
The arterial system is all of the arteries of the body, which carry blood leaving the heart.
The heart is the pump of the CVS system.
The Venous system is all of the veins of the body, which carry blood returning to the heart.
The CVS is divided into 2 main circulations, what are these? Describe them.
The Systemic circulation: oxygenated blood leaves from the left heart, to the capillary beds of organs tissues, and returns to the right side of the heart deoxygenated.
The Pulmonary circulation: deoxygenated blood leaves the right side of the heart, to the lungs and returns to the left side of the heart. oxygenated.
How do pulmonary arteries differ from the systemic arteries?
The pulmonary arteries carry deoxygenated blood, whereas the systemic arteries carry oxygenated blood.
How do pulmonary veins differ from the systemic veins?
The pulmonary veins carry oxygenated blood from the lungs, to the left heart, whereas the systemic veins carry deoxygenated blood from the body to the right heart.
In regards to the systemic circulation, what type of blood do arteries and veins carry?
Arteries carry well oxygenated blood, and veins carry deoxygenated blood.
Where does the heart lie?
Deep to the body of the sternum and costal cartilages. It lies in the thoracic cavity, in a space between the lungs called the mediastinum. It is slightly left of the midline.
What is the mediastinum? What is it divided into? In which part is the heart located?
The mediastinum is the area that lies in between the lungs. It is divided into a superior and inferior mediastinum. The inferior mediastinum is further divided into: anterior, middle, and posterior. The heart is located in the middle mediastinum.
What is the pericardium? Describe its layers and their functions.
The pericardium is found in the middle mediastinum, it is a sac surrounding the heart.
Outer layer of fibrous pericardium, which is tough, thick, and protective. It prevents overfilling & protects from penetrative injuries.
Deep layer of serous pericardium, membranous and glistening, it secretes serous fluid and reflects back onto itself. The parietal serous pericardium lines the fibrous pericardium. The visceral serous pericardium lines the heart. They are continuous with each other.
List, in order from superficial to deep, the layers of the heart.
- External: Visceral serous pericardium, aka the Epicardium.
- Middle: The myocardium (muscle layer).
- Internal: Endocardium. The internal lining, which is continuous with the endothelium of the blood vessels connecting with the heart.
List the surfaces and borders of the heart.
Anterior surface: formed mainly by the right ventricle.
The right auricle (ear), a muscular appendage of the right atrium.
The left auricle. Flap on the anterior surface of the left atrium.
Pulmonary trunk. Superior vena cava. Apex of the heart. Base of the heart/posterior surface (opposite the apex & formed of both atria). The inferior/diaphragmatic surface of the heart (formed of both ventricles).
The right heart border, which is formed by the right atrium. The left lateral border, which is formed by the left ventricle.
What is meant by the term septum?
There are two sides of the heart. Right and left, which are divided by a septum.
State the direction that blood flows through the great vessels, and cardiac chambers, including the locations of the valves.
Deoxygenated venous blood flows through the SVC and IVC to the right atrium. It then flows from the right atrium, the right ventricle through the Tricuspid valve. It leaves the RV through the pulmonary valve to the pulmonary trunk, and then the pulmonary arteries, to the lungs.
Oxygenated blood from the lungs returns to the heart via the L&R pulmonary veins, to the left atrium. Blood exits the left atrium to the LV through the bicuspid/mitral valve. It then leaves the LV through the aortic valve, to the aorta.
What is the general function of the cardiac valves? Where is each located?
Cardiac valves are present to ensure uni-directional blood flow. There are 4 cardiac valves, 1 between each atrium and ventricle, and 1 between each ventricle and the vessel leaving it.
The tricuspid valve lies between the RA and RV.
The pulmonary valve lies between the RV and the pulmonary trunk.
The mitral/bicuspic valve lies between the LA and the LV.
The aortic valve lies between the LV and the aorta.
Describe the normal route of electrical conduction between the atria and ventricles.
Spontaneous electrical impulse arises at the SA node. This then travels to the AV node, at the atrioventricular septum. It then travels down the right and left bundles in the interventricular septum, and spreads out to the myocardium through the conducting fibres. It is important in coordinated contraction of the cardiac chambers.
What is the crux of the heart?
It is the junction of all 4 chambers. A fibrous cardiac skeleton which acts as an electrical insulator.
What is fibrillation?
Uncoordinated contraction of myocytes that results in inefficient pumping, which can be fatal if it affects the ventricles.
Which “external factors” can affect the heart?
Nerves, reflexes and hormones.
What types of nerves supply the heart?
Sensory (pain) nerves.
Motor nerves: supply nodes and myocytes.
What role do sympathetic and parasympathetic nerves have on the heart?
Sympathetic nerves speed up heart rate and increase force of contraction.
Parasympathetic nerves slow heart rate.
What role do circulating hormones have on the heart?
Adrenaline/epinephrine, speeds up the heart and increases force of contraction.
Name, and give examples of the 3 different types of muscle.
Cardiac muscle (involuntary, striated muscle)- enables heart to beat. Found in the myocardium.
Smooth muscle (involuntary, non-striated muscle). Found in blood vessels, intestines and the airways.
Skeletal muscle (voluntary, striated muscle)- mainly responsible for skeletal movements.
Describe a skeletal muscle using the terms muscle belly, fascicle, myocyte, myofibril, sarcomere and myofilaments.
The muscle belly is the widest part of the muscle.
Skeletal muscle is made from fascicles, which are made from muscle fibres i.e. myocytes/muscle cells. Muscle fibres are made of myofibrils, which are made of many actin and myosin microfilaments.
Why do skeletal muscles appear striped when viewed histologically?
This is due to overlapping actin and myosin.
Define the term “muscle strain”?
If a skeletal muscle is “strained”/”pulled”, this means that some of the muscle fibres are torn. The more fibres torn, the worse the strain.
List, and give an example of the types of skeletal muscle.
Circular muscle, e.g. orbicularis oculi.
Pennate, e.g. the deltoid.
Quadrate, e.g. the rectus abdominis.
Flat muscle, with aponeurosis, e.g.the external oblique.
Fusiform, e.g. the biceps brachii.
What must a muscle do, in order to produce movement at a joint?
It must cross/span the joint. Skeletal muscles can only move a joint if they cross it, i.e. they have to cross a joint and attach to bones on either side of it.
What is an aponeurosis and what does it do?
It is a flattened tendon, which attaches muscle to soft tissue, rather than bone.
What happens to skeletal muscles and tendons during contraction?
Muscles shorten during contraction, along the axis/es between the origin and insertion. The origin and insertion of tendons move closer together during the movement produced by contraction.
Describe skeletal attachment. What is the role of tendons?
Skeletal muscles usually attach to bone via tendons. There is usually at least 2 points of attachment to bone, the origin on one side of a joint, and the insertion on the other side.
Tendons attach the muscle (usually) to bone, and are found at either end of the muscle. They are non-contractile.
What is the difference between a tendon and an aponeurosis?
A tendon attaches skeletal muscle to bone. An aponeurosis is a flattened tendon which attaches muscle to soft tissue, rather than bone.
Define the terms origin and insertion, with regards to the biceps brachii muscle.
The biceps brachii muscle has 2 origins. The short head of the bicep originates from the coracoid process at the top of the scapula. The long head of the bicep originates from the supraglenoid tubercle of the scapula.
It has one insertion. It attaches to the radius bone of the forearm.
What can a skeletal muscle do?
The only thing a skeletal muscle can do, is to contract, bringing its origin(s) and insertion(s) closer together, to produce movement.
What are the three main action of the biceps brachii, how does it achieve these?
- Flexion of the shoulder joint. It spans the anterior shoulder joint.
- Flexion of the elbow joint. It spans the anterior elbow joint.
- Supination of the forearm. It spans the anterior proximal radioulnar joint.
How can the main actions of a muscle be worked out?
Consider:
- Which joint(s) is/are spanned.
- The long axis of the muscle fibres.
- The aspect(s) of the joint(s) that is/are spanned.
- The shapes of the articular surfaces of the joint(s): do they limit movement in any direction?
Describe the anatomy of the deltoid muscle.
The deltoid muscle crosses the shoulder joint, but can cause different movements as it has muscle fibres in different orientations.
- Posterior fibres allow shoulder extension.
- Middle fibres allow abduction of the shoulder.
- Anterior fibres allow flexion of the shoulder.
It has 3 origins.
- Origin on the spine of the scapula.
- Origin on the acromion process of the scapula.
- Origin on the lateral 1/3 of the clavicle .
It has 1 insertion, on the deltoid tuberosity of the humerus.
Describe how the shape of the articular surfaces of a joint may permit or limit movements in certain directions.
The shape of an articular surface determines the type of movement, and the range of movement of a muscle.
- The shallow socket of the glenoid fossa of the scapula permits circumduction of the shoulder.
- The trochlear notch of the proximal ulna, and trochlea of the distal humerus permits flexion/extension.
Skeletal muscles are usually named according to a combination of what?
- Shape (latin/greek name).
- Location (body/region).
- Size (e.g. major/minor).
- Main bony attachment.
- Main movement.
State the process of clinical examination of a skeletal muscle & its function.
- Quadriceps. Test using the “knee jerk” reflex. A tendon hammer is used to apply a brief, sudden stretch to the muscle via its tendon. Its normal reflex response to being stretched, is to contract. Reflex contraction results in a brief twitch of the muscle belly/a movement in its normal direction. A normal stretch reflex indicates it is functioning normally.
What does a normal stretch reflex indicate?
That the following are functioning normally:
- The muscle.
- Its sensory nerve fibres.
- Its motor nerve fibres.
- The spinal cord connections between the two.
- The neuromuscular junction.
- Descending controls from the brain.
Define the term reflex.
A reflex is a rapid, predictable, involuntary reaction to danger. It is an unconscious movement done automatically by the nervous system and muscles. Nerve connections are at spinal cord level, the brain is not involved.
Define flexion withdrawal reflex.
Occurs when we touch something potentially damaging, and there is a sudden flexion to withdraw from the danger.
Define stretch/deep tendon reflex.
Muscle contraction in response to being stretched. It results in a brief twitch of the muscle belly/movement in the normal direction. It is protective against overstretching.
What are the 4 deep tendon/stretch reflexes?
- Biceps jerk.
- Triceps jerk.
- Knee jerk.
- Ankle jerk.
Define sensory nerve.
Nerve which carries sensory information toward the CNS. In deep tendon reflexes, the sensory nerve of a muscle detects the stretch and relays it to the spinal cord.
Define synapse.
A synapse is a communication in the spinal cord, between the sensory and motor nerves.
Define motor nerve.
A motor nerve, passes a message from the spinal cord, telling the muscle to contract.
Define neuromuscular junction.
The neuromuscular junction is the synapse where a motor nerve communicates with the skeletal muscle.
What is a reflex arc?
A reflex arc is the whole route taken by the action potentials.
Define descending controls.
x
What is required for a muscle cell to be able to contract?
A functioning motor nerve supply.
Define muscle paralysis. What would be seen upon examination of a paralysed muscle?
A muscle without a functioning motor nerve supply is said to be paralysed. A paralysed muscle cannot contract. On examination, the muscle would have reduced tone as it has reduced resistance to stretch i.e. floppy.
Define muscle spasticity. What would be seen upon examination of a spastic muscle?
The muscle has an intact and functioning motor nerve, but the descending controls from the brain are not working.
Upon examination, the muscle would have increased tone, as it is being allowed to over-contract, and has increased resistance to stretch.
Define muscle atrophy. How does this occur?
Muscle atrophy is a wasting of the muscles. Muscle fibres (myocytes) become smaller, reducing the muscle’s bulk.
It develops as a result of inactivity, i.e. immobilization after fracture, damage to motor nerve supply.
Define muscle hypertrophy.
Opposite of muscle atrophy. Skeletal muscles enlarge, and each individual myocyte enlarges.
Define hyperplasia.
Increase in cell number.
Where are most skeletal muscles found, in relation to the layers of the skin and fascia?
Skeletal muscles are usually found deep to fascia. They have a covering of tough fibrous connective tissue.
Epidermis-> Dermis-> Superficial fascia-> Deep fascia -> Skeletal muscle.
Explain the term compartment syndrome.
It is where fascia creates an enclosed space, and increased pressure as a result of tissue swelling/fluid build up affects the functions of the muscles or nerves in the compartment. It may be acute or chronic.
What is a fasciotomy?
Fascia is cut to relieve pressure, commonly in acute compartment syndrome.
What is meant by the term “limb fascial compartments”?
It is a section of the body containing muscles and nerves, surrounded by fascia.
How many fascial compartments do the thigh and the leg (i.e. the lower limb) each have?
The thigh has 3 compartments: anterior, medial and posterior.
The leg also has 3: the anterior, posterior, and lateral.
How many fascial compartments do the arm and the forearm (i.e. the upper limb) each have?
The arm has 2 compartments: anterior and posterior.
The forearm also has 2 compartments: anterior and posterior.
Explain where skeletal muscle transitions to smooth muscle in relation to the respiratory and alimentary tracts.
Skeletal muscle of the respiratory and alimentary tracts transitions to smooth muscle at the trachea, and the middle third of the oesophagus. This transitions back to skeletal muscle at the perineum.
Explain the protective reflexes and voiding of the respiratory and alimentary tracts? Which type of muscle are responsible for these?
Skeletal muscles of the proximal respiratory/alimentary tracts perform the protective reflexes of coughing, sneezing, gagging, swallowing and vomiting.
Skeletal muscles also provide the voiding functions, i.e. micturition and defecation.
Define gamete. Where are they formed?
A gamete is a haploid cell, produced by the gonads.
If it originates from the male it is a spermatozoa and is formed by the testes.
If it originates from a female, it is an oocyte or ovum, and is produced by the ovaries.
Describe the location of the pelvic cavity, the pelvic inlet and the pelvic outlet.
The pelvic cavity lies within the bony pelvis, it is continuous with the abdominal cavity.
It sits between the pelvic inlet and the pelvic outlet.
The pelvic outlet lies inferiorly to the pelvic cavity, and is the way into the perineum from the pelvis.
The pelvic inlet is superior to both the pelvic cavity, and outlet and is the way into the pelvic cavity from the abdominal cavity.
What is the pelvic floor?
The pelvic floor is an internal wall of skeletal muscle that separates the pelvic cavity and the perineum.
Describe the perineum’s anatomical position in relation to the pelvic floor.
The perineum lies inferior to the pelvic floor, between the proximal parts of the lower limbs.
What openings exist within the pelvic floor, and why?
Distal alimentary canal, renal and reproductive tracts. Enable defecation, urination and reproduction.
Describe the relationship between the abdominal cavity, parietal peritoneum and peritoneal cavity.
The pelvic roof is formed by parietal peritoneum. The parietal peritoneum lines the wall of the abdominal cavity, and drapes over the pelvic viscera.
The peritoneal cavity is the space that exists between the parietal peritoneum and the visceral peritoneum that lines the abdominal viscera.
What is the pouch of Douglas, what is its alternative name and its clinical significance?
It is also known as the recto-uterine pouch. In the anatomical position, this is the most inferior part of the peritoneal cavity in females.
It is clinically significant as any abnormal fluid in the peritoneal cavity will collect in the pouch of douglas in the upright position.
What is the vesicouterine pouch, and what is its clinical significance?
Double fold of peritoneum located between the uterus and bladder of a female. It is an important anatomical landmark for chronic endometriosis.
What organs lie within the female pelvis?
The uterus, uterine tubes, ovaries, the rectum, the bladder, the vagina and the perineum.
Name the female reproductive organs, and accessory organs.
The female reproductive organs are the ovaries.
The accessory reproductive organs are the uterine tubes, the uterus, and the vagina.
What layers make up the wall of the uterus’s body.
It has 3 layers, the perimetrium, the myometrium, and the endometrium.
Describe the locations and process of ovulation, fertilisation, implantation and menstruation.
The ovum develops in the ovaries.
During each menstrual cycle, 1 ovum is released from the surface of the ovary into the peritoneal cavity where it is gathered by fimbriae into the infundibulum of the uterine tube. It is moved along the uterine tube by cilia.
Fertilisation: the ovum can then be fertilised by sperm, which usually occurs in the ampulla.
Implantation: the fertilised ovum implants in the body of the uterus.
Menstruation: If unfertilised, it is expelled by contractions of the myometrium.
The fimbriated end of the uterine tube opens into the peritoneal cavity, what is the clinical significance of this?
There is potential for an ectopic pregnancy to occur within the abdomen.
It also enables STIs to spread via the uterus and uterine tubes to the peritoneal cavity, causing peritonitis.
Define ectopic pregnancy, what are the risks associated with this?
Fertilised ovum implants outwith the uterine cavity. Danger of haemorrhage.
Where are the most common locations for ectopic pregnancies to occur?
The uterine tubes, and the abdomen.
How is female sterilisation carried out? How do STIs cause this?
Tubal ligation. Both uterine tubes are clipped/cut/cauterised which blocks the lumen. STIs may also cause infertility by damaging/occluding the uterine tubes.
Describe the surface anatomy of the female perineum.
ANTERIOR
The external urethral orifice (urinary tract).
The vaginal orifice (female genital tract).
The anus (GI tract). POSTERIOR
Describe the surface anatomy of the male perineum. What is the anatomical position of the penis?
ANTERIOR
The anatomical position of the penis is erect.
The external urethral orifice.
The prepuce/hood of the penis.
The urethra (for passing urine and ejaculation of sperm).
Scrotum (contains the testes).
Anus.
POSTERIOR
Where do the testis begin development, and what is their route of descent to the scrotum?
The testis begin development on the posterior wall of the abdominal cavity.
By birth they have descended into the scrotum through the anterior abdominal wall via the inguinal canal.
Where are spermatozoa produced and at what temperature? How many are produced per second, and how long do these take to mature?
Sperm are produced in seminiferous tubules, at a temperature ~1oC below body temperature. They take 64 days to mature, and 1500 are produced every second.
State the function and location of the dartos muscle?
The dartos muscle is a smooth muscle within the superficial fascia of the scrotum. It helps to control sperm temperature by contracting to wrinkle/thicken scrotal skin and reduce surface area to maintain the correct scrotal temp. in cold conditions.
Describe the route taken by sperm from the seminiferous tubules to the vas deferens.
Sperm are produced in seminiferous tubules, and pass to the rete testis, then into the head of the epididymis, which later becomes the vas deferens.
What three things does the spermatic cord contain? How does each spermatic cord pass through the abdominal wall to reach the pelvic cavity?
The Vas deferens, the testicular artery, and the pampiniform plexus of veins.
Each spermatic cord passes through the anterior abdominal within the inguinal canal to reach the pelvic cavity.
What is torsion of the testis, and why is this dangerous?
It is the twisting of the spermatic cord, which disrupts blood supply. It causes severe pain and may cause testicular necrosis, resulting in male infertility.
Describe how semen reaches the external urethral meatus during ejaculation.
The vas deferens joins with the seminal glands, forming the ejaculatory duct (contains seminal fluid, sperm+seminal fluid = semen).
The right and left ejaculatory ducts join together within the prostate gland and drain into the urethra. The urethra exits the body via the external urethral meatus.
Briefly outline the process and reasoning of a vasectomy.
During a vasectomy, the vas deferens is transected and its lumen sutured closed (bilaterally). It is used in men who no longer wish to have children.
What are the male reproductive and accessory reproductive organs?
Reproductive: testes.
Accessory: vas deferens, seminal glands, prostate gland and penis.
List, in the correct order, the names of the parts of the upper and lower respiratory tracts.
URT:
- the R&L nasal cavities or the oral cavity.
- The pharynx.
- The larynx.
LRT:
- The trachea.
- The R&L main bronchi.
- The lungs: lobar bronchi, segmental bronchi, bronchioles and alveoli.
At which vertebral level does the upper respiratory tract become the lower respiratory tract?
At C6, the larynx becomes the trachea.
NB: the pharynx becomes the oesophagus at C6.
State the number of, define/name, the lung lobes and bronchopulmonary segments.
There are five lung lobes, which are areas of lung supplied by a lobar bronchus. These are the: right upper lobe, right middle lobe, and right lower lobe. The left upper lobe, and the left lower lobe.
A bronchopulmonary segment is a division of the lung supplied by a segmental bronchi.
There are 10 segmental bronchi within the right lung: 5 lower, 2 middle, and 3 upper.
There are 8 within the left lung: 4 upper, and 4 lower.
What is a fissure (with regards to the lungs)?
A fissure is a deep crevice, which separates the lobes from each other.
Why is each lung lobe and bronchopulmonary segment essentially a separate functional entity? Why is this clinically significant?
Each lung lobe and bronchopulmonary segment has its own air supply, blood supply, lymphatic drainage and nerve supply. This enables surgeons to remove a segment of lung rather than the whole lung/lobe.
Define respiratory epithelium.
Respiratory epithelium is the lining of the inside of the bronchial tree, with the exception of the distal bronchioles and alveoli.
What is meant by the term “mucociliary escalator”.
Mucous glands secrete mucous onto the epithelial surface which is swept superiorly to the pharynx by cilia, to be swallowed.
What effect does cigarette smoke and dry conditions have on the mucociliary escalator?
These interfere with the ability of the escalator to clear foreign bodies (including bacteria) from the LRT. Drying/cooling of the mucosa, and exposure to cigarette toxins interferes with the normal beating of cilia.
Describe, in general terms, the arrangement of hyaline cartilage and smooth muscle within the walls of the respiratory tree.
Hyaline cartilage supports the walls of the trachea, and all the bronchi, assisting with the maintenance of airway patency. It gradually reduces distally in the respiratory tree.
Smooth muscle in airway walls becomes progressively more prominent, distally. It is the most prominent feature of the bronchioles. This enables bronchioles to constrict and dilate.
State and explain the main requirements for adequate diffusion of respiratory gases at the level of the alveolar wall.
Alveoli must have no cartilage or smooth muscle present in their walls, as this would impact on diffusion. For adequate diffusion of respiratory gases, alveolar walls must be incredibly thin.
Summarise the main dangers to air moving freely through the upper and lower respiratory tracts. Give examples.
The respiratory tract may become narrowed:
- bronchiole constriction (e.g. asthma).
- Mucosal swelling & overproduction of mucous (e.g. asthma).
- An external tumour may compress the respiratory tract.
Foreign bodies may be inhaled into the respiratory tract, and may partially or completely stop breathing.
How is patency of the URT maintained? Describe the basic skeletal structure of these.
The R&L nasal cavities, which are separated by the nasal septum (bony posterior part: the ethmoid bone superiorly and the vomer inferiorly. Cartilaginous anterior part: septal cartilage (hyaline)).
The oral cavity.
The hyoid bone, which is horseshoe-shaped. and unique as it does not attach to any other bone of the body.
The larynx, which consists of several cartilages: the epiglottis, the thyroid cartilage, the cricoid cartilage and the 2 arytenoid cartilages.
The trachea, which is the inferior continuation of the larynx.
Describe the basic anatomy of the rima glottidis and the vocal cords (ligaments).
The rima glottidis is the narrowest part of the larynx (where foreign bodies tend to block the URT). It is the opening between the vocal cords and the arytenoid cartilages.
The vocal cords can approximate in the midline, closing the rima glottidis and preventing a foreign body being inhaled into the trachea.
State the general functions of the vocal cords.
Help to prevent entry of foreign bodies into the LRT, by approximating in the midline and closing the rima glottidis. They produce sound (phonation) and speech (articulation).
What functions protect the lower respiratory tract?
The vocal cords approximating in the midline to close the rima glottidis and prevent inhalation of a foreign body into the trachea. A cough reflex is then stimulated to expel the foreign body via the pharynx and oral cavity.
Describe and explain the functioning of the Heimlich manoeuvre.
Used when a foreign body blocks the URT, and the cough reflex is not possible as a breath in cannot be taken.
The Heimlich manoeuvre attempts to raise abdominal pressure, forcing the diaphragm superiorly and raising the pressure in the chest, and subsequently the lungs. This will then force air from the lungs, into the trachea, which will force air through the rima glottidis to expel the foreign body.
Describe the basic anatomy of how the air breathed in is normally warmed, humidified & “cleaned”.
The nasal conchae increase surface area of the lateral walls of the nasal cavities, to produce turbulent flow-> bringing air into contact with the walls. The respiratory mucosal epithelium of the nasal cavities has a good arterial blood supply, and warms the air. The mucosa produce mucous, providing moisture. The mucous also traps potentially infected particles, and the cilia of the mucosa waft the mucous to the pharynx to be swallowed.
The tonsils are part of the lymphatic system and are located within the mucosa lining the pharynx. They produce white blood cells to defend against infecton.
Describe the basic anatomy of the chest wall (how we protect our lungs).
The main danger to the lungs is penetrating injuries.
The chest wall is composed of skin &fascia, bone, skeletal muscle, the diaphragm and parietal pleura.
The bones are the 12 pairs of ribs, the clavicles, the scapula, the 12 thoracic vertebrae, and the sternum (=manubrium, sternal angle at rib 2, the body & xiphoid process). Intercostal spaces exist between the ribs, and are potential weaknesses.
There are 3 layers of skeletal muscle: external intercostal, internal intercostal and the innermost intercostal muscles. The diaphragm is the main muscle of respiration.
The parietal pleura is the internal lining of the chest wall. The visceral pleura lines the lung lobes. Between these layers lies the pleural cavity.
Define the GI/alimentary/digestive tract.
It is a continuous tube commencing at the oral cavity, and ending at the anus. It is lined by mucosa (epithelium + lamina propria) and has muscle within its walls.
It is the route in which we normally introduce food/liquids, digest &; absorb nutrients/toxins, & excrete residual waste out of the body.
What makes up the upper GI tract?
Oral cavity, pharynx (oropharynx and laryngopharynx), oesophagus, stomach and small intestine.
What makes up the lower GI tract?
The caecum, appendix, colon, rectum, anal canal and anus.
Relate the different parts of the GI tract to the anatomical regions they are located in.
The oral cavity and pharynx are located in the head.
The pharynx and oesophagus lie within the neck. The oesophagus also lies within the chest.
The abdomen contains the stomach, the small intestine, and most of the large intestine.
The pelvis contains the rectum and the anal canal.
The anus is located in the perineum.
What are the general functions of the oral cavity?
Sensing, salivation, chewing, and initiating swallowing.
What are the general functions of the pharynx?
Defends against infection (tonsils), role in swallowing and airway protection.
What are the general functions of the oesophagus?
Allows transit from the pharynx to the stomach.
What are the general functions of the stomach an small intestine?
Transit, digestion and absorption of food. They defend against infection (acid).
What are the general functions of the large intestine and anus?
Transit. Reabsorption of water and electrolytes. Stool formation. Waste excretion.
State the overriding functional principle of the upper GI tract.
To ensure that solids and liquids SAFELY enter and exit the stomach.
What dangers exist within the upper GI tract?
Poison, sharp or excessively hot/cold substances, bacteria/viruses, obstruction and aspiration.
Identify the anatomical relations of the oral cavity.
The hard palate lies superior to the oral cavity, and inferior to the nasal cavity. The oral cavity contains the tongue and teeth/dentition. The mandible sits anteriorly to the oral cavity.
The muscle of the floor of the mouth lies inferiorly to the oral cavity, posterior to the mandible, and anterior to the hyoid bone which attaches to the epiglottis.
Define the term mastication, & list the muscles of mastication.
Mastication, i.e. chewing, is the process by which food is crushed and ground by teeth. It is the first stage of digestion.
The muscles of mastication open and close the jaw at the TMJ. There are 4 in total.
3 close the jaw: the temporalis, the masseter, and the medial pterygoid.
1 opens the jaw: the lateral pterygoid.
Define the term “muscles of facial expression”.
Muscles of facial expression lie between the superficial fascia, and the fascia skeleton. Their contraction causes the skin of the face to be pulled into different expressions.
Describe the orbicularis oris, and state its roles in mastication.
The orbicularis oris is a circular muscle surrounding the mouth. It lies within the lips. During mastication it prevents dribbling.
Describe the buccinator, and state its roles in mastication.
The buccinators is a muscle of the cheek, posterior to the orbicularis oris. It aids in manipulation of food, positioning it between the occlusal surfaces of the teeth.
Describe the basic surface anatomy of the oral cavity.
Upper dental arch(teeth), Hard palate and soft palate (roof of mouth). The arches of the soft palate, and the palatine tonsil lie at the posterior aspect of the oral cavity, along with the uvula.
The lower dental arch is superior to the gingiva. The tongue lies at the inferior aspect.
The oral cavity is lined with stratified squamous mucosal epithelium for protection. Keratin is present, only on the gingivae and hard palate.
State the types of sensation detected by the oral cavity.
It is one of the most sensitive body areas. It can feel general sensation, i.e. pain, touch, temperature, proprioception. It also has the special sensation of taste.
Name the 3 types of papillae of the lingual (tongue) mucosa.
Anterior 2/3 of the tongue:
Foliate papillae, lateral side of the tongue.
Vallate papillae, posterior.
Fungiform papillae, medial.
These are all singular papilla, with taste buds.
The filiform papillae, anterior, are associated with touch, temperature, etc.
Describe in general terms the skeletal muscular structure of the tongue (extrinsic & intrinsic groups) and state their general functions.
Extrinsic muscles of the tongue exist as four pairs, they attach to the bony skeleton and move the tongue around during mastication, speech and swallowing.
The intrinsic muscles of the tongue exist as 4 pairs in various directions, and change the shape of the tongue during function.
Describe the adult dentition in terms of total number of teeth, types of teeth and quadrants.
32 teeth in adult dentition (18years+).
Types: molars, premolars, canines, incisors.
There are 4 quadrants: upper right, upper left, lower right, and lower left.
It says know how to annotate a tooth when writing a patient’s notes, but u r not dentist, so no x
No.
Define occlusion. What is the clinical significance of asking a patient how their “bite feels”?
Occlusion (bite), describes the way the upper and lower dental arches fit together.
Patients are sensitive to changes in their occlusion. It is clinically significant as a displaced fracture of the angle/body of the mandible or the maxilla, may affect their occlusion.
Define salivary glands. State the major and minor surface anatomy of their locations, and their respective functions.
They are accessory organs of the upper GI tract.
Major glands (3 bilateral pairs): Parotid gland (near ear), Submandibular (under mandible), Sublingual (under tongue). Produce saliva, a solute allowing taste. It contains mucin to aid swallowing & speech, and to keep mucosa moist.
Minor glands: 1000’s in the oral mucosa, they carry out basal secretion to keep the mouth moist.
Describe the surface anatomy of the ducts of the 3 major salivary glands.
Parotid gland: parotid duct, crosses the face and secretes into the mouth by the upper 2nd molar.
Submandibular gland: submandibular ducts, enters the floor of the mouth and secretes via the lingual caruncle.
Sublingual gland: lies in the floor of the mouth and secretes via several ducts, superiorly.
What might cause salivary glands to swell?
Duct obstruction/clogging can cause swelling due to back up of secretions.
Describe the 3 parts of the pharynx.
The pharynx has 3 parts:
Nasopharynx: posterior to the nasal cavity, and superior to the soft palate.
Oropharynx: posterior to oral cavity, between the soft palate and the epiglottis.
Laryngopharynx: posterior to larynx, between the epiglottis and oesophagus.
Describe the tonsils, and their functions.
Waldeyer’s tonsillar ring: adenoid (superiorly), tubal tonsils (pair) lie lateral and slightly inferior to this. The palatine tonsils (pair) lie posterior and inferior to these. The lingual tonsil lies on the posterior aspect of the tongue.
Their function is to defend against invading pathogens.
Describe the two layers of skeletal muscles, and their functions, within the pharynx walls.
Outer circular layer: 3 constrictor skeletal muscles (superior, middle, & inferior pharyngeal constrictors), which push food bolus inferiorly towards the oesophagus during sequential contraction.
Inner longitudinal layer: 3 paired vertical skeletal muscles (e.g. stylopharangeus). During contraction, they pull the larynx superiorly, shortening the pharynx during swallowing.
What common danger exists between the URT and the upper GI tract?
The oropharynx and laryngopharynx are used in both pathways, and there is therefore a risk of aspirating material into the respiratory tract.
The chance of this is increased by the raising of the larynx. If it does occur, then the cough reflex engages.
List, in the correct order, the skeletal muscles involved in swallowing and their role.
Muscles of mastication (i.e. lateral pterygoid) opens the mouth.
All muscles of mastication are then used to chew the food (medial &lateral pteryogid, temporalis and masseter).
The orbicularis oris prevents dribbling.
The intrinsic and extrinsic muscles of the tongue, along with the buccinateor are involved in bolus manipulation.
The muscles of the tongue push the bolus towards the pharynx to be swallowed.
Longitudinal muscles shorten the pharynx, drawing the larynx superiorly towards the epiglottis, closing the laryngeal inlet.
Constrictor muscles sequentially contract to push bolus towards oesophagus.
Oesophagus then continues to push the bolus towards the stomach (note the transition from skeletal, to smooth muscle, mid-oesophagus.
Describe the oesophagus in general terms & in terms of muscle type.
It is an inferior continuation of the laryngopharynx, and lies posterior to the trachea.
Its function is to transmit food & liquids from the pharynx to stomach.
It is a muscular tube, which gradually transitions from skeletal, to smooth muscle. It is lined with non-keratinized, stratified squamous epithelium.
What is the function of the small intestine?
Responsible for transit, digestion and absorption of food/nutrients.
What is the function of the large intestine?
Transit, reabsorption of H2O & electrolytes, and stool formation.
List, in the correct order, the parts of the small intestine.
Three parts (proximal to distal): duodenum, jejunum, ileum.
List, in the correct order, the parts of the large intestine.
Caecum, ascending colon, transverse colon, descending colon, sigmoid colon.
The appendix attaches to the caecum.
At what vertebral level does the oesophagus pierce the diaphragm?
T10
Describe the basic structure of the walls of the GI tract.
Outer longitudinal layer of smooth muscle (shortens the tube), and inner circular layer of smooth muscle (constricts the diameter).
Name the types of mucosa lining the parts of the GI tract, from the stomach to the large intestine.
Stomach is lined with secretory cells.
Small intestine is lined with absorptive cells.
Large intestine is lined with absorptive cells.
Define peristalsis.
Waves of simultaneous shortening of the length, plus narrowing of the luminal diameter of a segment of the GI tract.
Define body wall.
Formed from skeleton and muscle.
Define body cavity.
The space surrounding the body wall.
List the body’s walls.
Head and neck, the thoracic wall, the back, diaphragm, abdominal wall, pelvic wall, and upper and lower limbs.
Name the body’s cavities.
Cranial, thoracic, abdominal and pelvic cavity.
In which cavities do the pleural and peritioneal cavities lie?
Pleural cavity lies within the thoracic cavity.
Peritoneal cavity lies within the abdominal cavity.
Define guarding. What is this a sign of?
Guarding is the tensing of the abdominal walls in response to pressure. It is a sign of peritonitis, the inflammation of the peritoneum, caused by infection/irritation.
Define retroperitoneum in terms of the posterior abdominal wall and the peritoneal cavity.
Describes a structure lying posterior to the peritoneum, out-with the peritoneal cavity and anterior to the posterior abdominal wall.
List the abdominal organs, and whether they are intra- or retroperitoneal.
Intraperitoneal: liver, gallbladder, stomach, tail of the pancreas, spleen, the first 5cm of the duodenum, the jejunum, the ileum, transverse colon, sigmoid colon, appendix and upper 1/3 of the rectum.
Retroperitoneal: P: pancreas (except the tail) U: ureters C: colon (ascending and descending K: kidneys E: eh the rest of the duodenum R: rest of rectum
What is a retroperitoneal organ, what is an intraperitoneal organ?
Retroperitoneal organs lie posterior to the peritoneum.
Intraperitoneal organs lie within the peritoneum.
What is a mesentery?
It is a double layer of peritoneum, connecting intraperitoneal organs to the body wall, and allowing passage of neurovasculature.
What suspends most of the small intestine from the posterior abdominal wall?
The mesentery of the small intestine.
Describe the abdominal organs as 3 embryologically derived parts.
Foregut, midgut and hindgut.
Describe how arterial blood reaches the foregut, midgut and hindgut organs from the abdominal aorta.
The coeliac trunk supplies the foregut.
The SUPERIOR mesenteric artery supplies the midgut organs.
The INFERIOR mesenteric artery supplies the hindgut organs.
Describe how venous blood from the absorptive parts of the GI tract reach the liver via the hepatic portal system.
Inferior mesenteric vein drains the hindgut via the splenic vein.
Superior mesenteric vein drains the midgut.
Splenic vein drains the foregut.
Hepatic portal vein is formed by the union of the superior mesenteric vein and the splenic vein, and carries venous blood to the liver.
How does venous blood from the liver reach the IVC?
Via hepatic veins within the systemic venous system.
What is the significance of the liver between the portal and systemic venous systems?
Portal venous system drains absorptive parts of the GI tract and associated organs to the liver via the hepatic portal vein. The systemic drains the rest of the blood to the right atrium of the heart (including the blood from the liver via hepatic veins).
The liver cleans the blood from absorptive parts, before it can combine with that of the systemic circulation.
Where do foregut structures drain their lymph nodes to, and along which artery?
Along the splenic artery, towards the coeliac nodes, located around the origin of the coeliac trunk.
Where do midgut structures drain their lymph nodes to, and along which artery?
Along the superior mesenteric artery, towards the superior mesenteric nodes (located near origin of SMA).
Where do hindgut structures drain their lymph nodes to, and along which artery?
Along the inferior mesenteric artery, towards the inferior mesenteric nodes (located near origin of IMA).
Define anatomical sphincter. What can they be composed of? Give an example.
Discrete areas where muscle completely encircles the lumen of the tract. They may be composed of smooth muscle (e.g. pyloric sphincter) or skeletal muscle (e.g. external anal sphincter).
How might the GI tract become obstructed?
External compression: e.g. tumour in adjacent structure.
Internal obstruction: e.g. mucosal tumour expanding within the lumen, an ingested foreign body.
How does the GI tract respond to obstruction? What might this cause?
Increased peristalsis proximal to the obstruction, in an attempt to dislodge it.
It may cause colicky pain.
Summarise the functions of the nervous system.
Controls the different systems within the body. Its functions include: sense, motor, reflex, thinking, emotion, memory.
Describe the general basic structural anatomy of the nervous system.
It is composed of the:
Central nervous system/CNS: brain + spinal cord.
Peripheral nervous system/PNS: spinal nerves + cranial nerves + autonomic nervous system.
Define central nervous system.
The central nervous system is composed of the brain, plus the spinal cord.
Define peripheral nervous system. What can this be divided into?
The peripheral nervous system is composed of somatic nerves, i.e. cranial and spinal nerves, plus the autonomic nerves.
The autonomic nervous system can be further divided into the sympathetic and parasympathetic nerves, and visceral afferents.
List the components of a neurone (nerve cell).
Nerve cells consisting of: dendrites, a body containing the nucleus, a myelin sheath acting as an electrical insulator, and an axon/nerve fibre which carries action potentials.
What is a nerve fibre? What relevance do these have to peripheral nerves?
A nerve fibre is a neurone’s axon. Peripheral nerves consist of many axons travelling together, to or from the same area of the body/structure.
Define peripheral nerve.
A nerve belonging to the peripheral nervous system.
Define a “named nerve”.
Bundles of axons travelling to or from the same area of the body. They are large enough to be seen during dissection.
Describe the basic anatomy/pharmacology of a synapse.
A synapse is the site of chemical communication between two or more neurons.
The action potential from one neurones becomes a chemical signal (neurotransmitter), and then returns to an electrical signal when it reaches the second neurone.
Identify, name & state the basic functions of the major parts of the cerebrum & brainstem.
Parietal lobe: integrates sensory information.
Occipital lobe: processes visual information.
Temporal lobe: processes auditory information.
Frontal lobe: carries out higher mental processes, e.g. thought, decision making.
Cerebellum: responsible for balance and coordination.
Brainstem: midbrain (temperature regulation, arousal, motor & visual control), pons (connects upper & lower brain) & medulla oblongata (sustains life e.g. breathing).
How many pairs of cranial nerves do we have? Name them and their numbers.
(also need to know whether it connects with cererbrum, thalamus, brainstem or spinal cord, but I cba).
12 pairs of cranial nerves, that are named and numbered. CN I: olfactory CN II: optic CN III: oculomotor. CN IV: Trochlear CN V: Trigeminal CN VI: Abducens CN VII: Facial nerve CN VIII: Vestibulocochlear/ acoustic CN IX: Glossopharyngeal CN X: Vagus CN XI: Spinal accessory CN XII: Hypoglossal
What is meant by “grey matter” of the brain and spinal cord?
Brain: cerebral cortex, it is the outer area and full of cell bodies.
Spinal cord: outer area, full of cell bodies.
What is meant by “ white matter” of the brain and spinal cord?
Brain: Inner area, contains many myelinated axons- which gives the white appearance.
Spinal cord: outer area, contains many myelinated axons.
Summarise the anatomy of the spinal cord, spinal nerve rootlets & roots, spinal nerves, spinal nerve rami (including plexuses) & named nerves.
The spinal cord connects with the brain stem, and passes inferiorly through the foramen magnum through the vertebral canal.
Spinal nerve rootlets attach to grey matter (posterior = sensory, anterior = motor), become roots. The anterior and posterior roots then merge to form a spinal nerve, which anterior and posterior rami (of mixed function) branch off.
There are 8 cervical spinal nerves, 12 thoracic, 5 lumbar, 5 sacral and 1 coccygeal. A total of 31 spinal nerve pairs. They are named according to the vertebrae above, except in the spinal region, where they are named according to the vertebrae below. C8 exits between C7 and T1.
What is the conus medullaris?
It Is the tapered, lower end of the spinal cord.
What is the cauda equina? What is it responsible for?
Collection of nerve fibres located at the end of the spinal cord, which exit the foramina of the vertebral bones of the spine.
Communicates sensory and motor nerve messages between the central nervous system and the organs from the pelvis, as well as the lower limbs.
What is a dermatome? In which dermatomes do the male nipples, and the umbilicus lie?
Dermatomes are areas of skin supplied by both the anterior and posterior rami of a spinal nerve. It divides the body wall into segments, each of which is supplied by a single pair of spinal nerves.
The male nipple lies in the T4 dermatome.
The umbilicus lies in the T10 Dermatome.
What is a nerve plexus? Describe the 4 body plexuses, are they unilateral, bilateral or medial?
Nerve plexuses are networks of intertwined anterior rami, composed of efferent and efferent nerve fibres.
- Cervical plexus: C1-C4 anterior rami, supply the posterior scalp, neck wall and diaphragm.
- Brachial plexus: C5-T1 anterior rami, supply upper limb.
- Lumbar plexus: L1-L4 anterior rami, supply lower limb.
- Sacral plexus: L5-S4 anterior rami, supply lower limb, gluteal region and perineum.
They are all bilateral.
Describe the sympathetic chains, and their locations.
Pairs of ganglionated longitudinal cords of the sympathetic nervous system, situated on either side of the vertebral column. The sympathetic trunk travels from the base of the skull to the coccyx, just lateral to the vertebral bodies.
Summarise the route taken by sympathetic nerves on leaving the CNS to reach their target organs.
Shorter preganglionic neurons originate from the thoracolumbar region of the spinal cord specifically at T1 to L2/L3, and travel to a ganglion, often one of the paravertebral ganglia, where they synapse with a postganglionic neuron. From there, the long postganglionic neurons extend across most of the body.
Summarise the route taken by parasympathetic nerves on leaving the CNS to reach their target organs.
All parasympathetic axons leave the CNS via cranial nerves III, VII, IX & X and via sacral spinal nerves. This is known as craniosacral outflow.
What do visceral afferent nerve fibres do?
They carry action potentials/sensations (e.g. touch, temperature, pain) from organs to the CNS and generally travel alongside sympathetic and parasympathetic nerves.
The nervous system can be divided into two functional divisions, what are these?
The somatic and autonomic nervous systems.
What are afferent and efferent nerves?
Afferent: sensory nerve.
Efferent: motor.
Define the endocrine system.
A collection of glands from around the body, responsible for manufacturing and releasing at least 1 specific hormone.
Define hormone.
A specific molecule produced by endocrine glands, aka chemical messengers, and involved in regulating: metabolism, growth, reproductive function and the bodies stress response.
Define target cell in regards to hormones.
The target cell of a hormone, is one which the hormone can bind to via its receptors, producing a specific effect.
Define receptor, in regards to hormones.
Receptors exist on target cells of the hormone, enabling it to bind to the cell to produce a specific effect.
Define homeostasis.
Homeostasis keeps the bodies physiological parameters within normal ranges, despite opposing external influences.
State the normal values for: Body temperature. Pulse Arterial blood pressure. Blood pH. Arterial oxygen saturation. Blood glucose
temp: 36.8oC.
pulse: 70bpm
ABP: 120/80mmHg
pH: 7.4
Arterial PO2: >95%
Blood glucose: 4-8mmol/L
Define negative feedback mechanism.
Changes in the system, that alter values outwith the normal range, are reversed by the process of negative feedback.
Define hyper- and hypo-secretion of hormones.
Hyper: too much secretion of hormone.
Hypo: too little secretion of hormone.
Name the main endocrine glands, and state the region of the body they are located in.
Head: hypothalamus and pituitary gland.
Neck: 4 parathyroid glands and the thyroid gland.
Abdomen (retroperineum): 2 adrenal glands and the pancreas.
Pelvis:
Female= 2 ovaries.
Male= 2 testes.
Describe the anatomy of the hypothalamus & pituitary gland, & their hormones.
The hypothalamus lies superior to the brain stem, is part of the diencephalon. Secretes: releasing hormones to stimulate anterior pituitary to release hormones. Release-inhibitory hormones: prevent anterior pituitary hormone release.
The pituitary gland (divided into anterior and posterior) is a midline structure in the pituitary fossa of the sphenoid bone.
Posterior: oxytocin and vasopressin/ADH.
Anterior: growth hormone, prolactin, TSH, ACTH, LH, FSH.
The infundibulum connects the hypothalamus to the pituitary gland.
Define, and give 2 examples of portal systems.
Two venous capillary beds joined by a portal vein.
- Hypophyseal portal system (endocrine).
- Hepatic portal system (GI).
Why is the pituitary gland the master gland?
It secretes hormone which can control the output of hormones from other endocrine glands.
Describe the anatomy of the thyroid and parathyroid glands, their blood supply & hormonal functions.
Thyroid gland lies anterior to the trachea, and inferior to the cricoid and thyroid cartilage. It uses iodine to produce T3 and T4, which regulate metabolism, and stimulate growth.
The 4 parathyroid glands lie laterally (2 on each side) of the thyroid gland. They manufacture and secrete parathyroid hormone, which controls the amount of calcium in blood and bone.
They are supplied with blood via the superior and inferior thyroid arteries. Blood drains via superior, middle, and inferior thyroid veins.
Describe the anatomy of the pancreas, its blood supply, the hormonal functions of the endocrine part and duct system/secretions of the exocrine part.
The pancreas is a retroperitoneal organ, overlying the L1/2 vertebra. It is posterior to the stomach, anterior to the aorta&IVC. Lies between the duodenum and spleen.
It receives blood from the coeliac trunk and SMA as it is both a fore- and mid-gut structure. Venous blood drains via the splenic vein and SMV into the hepatic portal vein.
2 anatomically and functionally distinct parts.
- ENDOCRINE PANCREAS: secretes insulin in response to islet of Langerhans cells detecting increased blood glucose.
- EXOCRINE PANCREAS: manufactures digestive enzymes and secretes them via a duct system (not the blood) into the duodenum.
Define exocrine gland.
They produce and secrete substances onto an epithelial surface by way of a duct.
Define diabetes mellitus.
Type 1: failure of pancreas to produce insulin.
Type 2: failure of target cells to respond to insulin.
Describe the anatomy of the adrenal (suprarenal) glands, their blood supply & hormones.
Retroperitoneal, bilateral, paired and located on top of the kidneys, but separated by a fascial septum.
Two anatomical and functional parts:
- ADRENAL CORTEX: secretes glucocorticoids, mineralcorticoids, and androgens.
- ADRENAL MEDULLA: secretes adrenaline and noradrenalin.
Glucocorticoids – influence metabolic rates of protein, fat and sugars (Cortisol)
Mineralocorticoids – regulate salt balance and impact on blood volume/pressure
Androgens – male sex hormones.
Supplied by L&R: superior renal arteries, middle suprarenal arteries, inferior suprarenal arteries. Venous drainage via the Suprarenal and renal veins to the IVC.
Describe the anatomy of the gonads, their blood supply & hormonal functions
Gonads is the collective term for the testes and ovaries.
Testes: located in the scrotum of the male perineum. Blood is supplied via the gonadal artery and veins, the inferior parts of the blood supply run within the spermatic cord. They secrete testosterone in response to LH from the anterior pituitary gland. Testosterone controls the male secondary sex characteristics, closure of epiphyseal growth plates and stimulates sperm.
Ovaries are broad ligaments of the female pelvis. They secrete oestrogen and progesterone in response to FSH & LH from anterior pituitary. Progesterone prepares uterus for pregnancy. Oestrogen controls the female secondary sex characteristics and ovum development.
Summarise the “essential to life” functions performed by the renal system.
Maintain homeostasis via blood pH control, fluid and electrolyte balance, BP control, metabolism of waste products & drugs. stimulation of RBC production, absorption of calcium.
What anatomical structures make up the renal system, where are they located and what epithelium lines them in terms of function?
Kidneys: produce urine. Located retroperitoneally in the abdomen.
Bladder: stores/voids urine. Its epithelium is adapted for urine storage and voiding i.e. capable of stretching. Located in the pelvis.
Ureters: drains urine. Proximal parts located retroperitoneally in the abdomen.
From the ureter to the urethra, the “tubes” are lined with transitional epithelium.
Urethra: excretes urine (and semen in the male). Distal urethra is protected by stratified squamous epithelium. Proximal part located in the pelvis, distal in the perineum.
Describe the kidneys in terms of location, surrounding vasculature and vertebral levels.
Retroperitoneal organs, left kidney lies lateral to IVC and right kidney lies lateral to aorta. They lie approximately at the T12-L3 vertebral levels.
Define the upper and lower urinary tracts.
What do infections of each involve?
upper: kidneys and ureters. Upper UTI infection may affect the kidneys.
lower: bladder and urethra. Lower UTI involves the urethra and bladder.
In which abdominal quadrants and regions do the kidneys lie.
Bilateral paired structures (left and right).
Left lies in LUQ and right in RUQ.
L&R hypochondrium
Epigastric
R&L lumbar
Umbilical
Describe the location of the kidneys in relation to the liver, spleen and diaphragm.
The kidneys lie inferior to the liver. The right kidney is pushed down by the liver, and so lies more inferiorly (L1-L3) than the left (T12-L2).
they lie inferiorly to the spleen.
As they lie beneath the diaphragm, the kidneys move with inspiration (inferiorly) and expiration (superiorly).
What structures protect the kidneys from trauma?
Being retroperitoneal i.e. posterior to other abdominal organs.
The transverse processes of the vertebral column.
Ribs 11 & 12.
Guarding by the skeletal muscles 9back, antero-lateral abdominal wall, posterior abdominal wall).
Renal/deep fascia.
Paraphrenic and perinephric fat.
Renal capsule.
Know the arterial blood supply to, and venous drainage from the kidney. What arteries supply the ureters?
Renal hilum structures: ureter, renal artery and renal vein. 5 segmental branches arise from each renal artery to supply nephrons. Venous drainage via L&R renal veins to the IVC.
Ureter: multiple arterial branches along its length, i.e. renal arteries, gonadal arteries, and the aorta.
What is a nephron?
It is the basic structural and functional unit of the kidney.
Describe the kidneys in terms of: capsule; cortex; medulla; pyramids; nephrons; collecting ducts.
The kidneys are contained within a renal capsule, lining the outer renal cortex.
There is an inner renal medulla, containing renal pyramids attached to renal papilla (collecting duct passes through pyramid to drain modified filtrate through papilla as urine).
The renal cortex contains the renal corpuscle (Bowman’s capsule + glomerulus) and the distal convoluted tubule.
The renal medulla contains the proximal convoluted tubule, the collecting duct, and the loop of Henle.
Describe the flow of urine through “tubes” in the correct order (from collecting duct to ureter only).
Urine from the nephron collecting ducts, drains to the minor calyx, to the major calyx, to the renal pelvis and then to the ureter.
State the 3 most likely sites for renal calculi or blood clots to obstruct the ureter.
- Pelviureteric junction.
- Ureter as it crosses the anterior aspect of common iliac artery.
- Ureteric orifice.
What property/characteristic do the walls of the ureters have and how does this aid them? What might this cause a patient to feel?
Ureter has smooth muscle in its walls, if obstruction occurs that may employ peristalsis in an attempt to flush the obstruction towards the bladder. This may cause colicky pain.
Where do ureters transport urine from and to?
from the renal pelvis to the ureteric orifices in the trigone of the bladder.
Where can kidney stones form? What are they mostly formed from and how can they be seen?
They may form within the urinary tract, are mostly formed from calcium salts and tend to be visible on x-ray.
What can happen if the urinary tract becomes obstructed?
It causes back pressure within, and dilatation of the urinary tract proximal to the obstruction. If untreated, it may cause renal failure.
where does the bladder lie? what covers its superior surface?
In the anterior part of the pelvis, immediately posterior to the pubic bones. It is covered by peritoneum on its posterior surface.
In which direction does the bladder expand as it fills?
Superiorly.
Give the location of the prostate and the uterus in relation to the bladder
Prostate lies inferior to the bladder. Uterus lies superior to the bladder.
which muscle is contained within the bladder wall (and is stimulated to contract by parasympathetic nerve fibres carried in pelvic splanchnic nerves)?
Detrusor muscle.
What is the difference between an orifice and a sphincter?
An orifice is an opening, whereas sphincters are muscle surrounding orifices controlling its opening and closure.
Name and know the location of the relevant orifices and sphincters (both smooth and skeletal muscle) of the urinary tract.
External urethral orifice (in perineum of females).
Internal urethral orifice in the bladder.
External urethral sphincter (voluntary skeletal muscle around urethra).
Internal urethral sphincter (involuntary muscle - detrusor - encircles ureteric orifices).
Outline the male urinary tract, clearly stating the shared territory with the reproductive tract.
Urinary tract: ureter, bladder, prostatic urethra, spongy urethra and external urethral orifice.
Shares the prostatic urethra, spongy urethra and external urethral orifice.
State the most common site of urethral obstruction in males, and a reason why this may occur.
The prostatic urethra.
- Benign prostatic hyperplasia. Prostate impinges on prostatic urethra causing obstruction.
Define urinary catheterisation and suprapubic catheterization.
Urinary catheterisation: insertion of a urinary catheter into the bladder via the urethra.
Suprapubic catheterization: insertion of a suprapubic catheter into the bladder via the anterior abdominal wall.
Compare the male and female urethras. What implications does this have for urinary catheterisation and the development of urinary tract infections (UTIs)?
The female urethra is much shorter, more distensible (elastic) and open within the perineum.
This means UTIs are more common in females, and they are also easier to catheterize.
Define the systemic & pulmonary circulations.
Systemic circulation: aorta, SVC and IVC.
Pulmonary: Pulmonary trunk and pulmonary veins.
Define great vessels.
Those directly connected to the chambers of the heart, i.e. the pulmonary trunk, IVC& SVC, aorta, and pulmonary veins.
Describe the relationship between arteries, arterioles, capillaries, venules and veins.
The arteries/arterioles and venules/veins are continuous with each other at the capillary beds of the organs & tissues
What does blood supply cells with? What does it remove from cells? Where does all this occur?
It supplies oxygen and nutrients, e.g. glucose, hormones.
It removes waste, e.g. CO2.
This occurs within the capillary beds (arteriole, capillaries, venules).
What are the basic principles in relation to arteries?
Proximal arteries are close to the heart, whereas distal arteries are far from the heart.
They are named usually on anatomical location/destination.
They are often part of a neurovascular bundle (artery, vein, nerve).
They give rise to branches, in order to supply a territory.
They often run a tortuous course.
Usually located deeper than veins (reduces chance of haemorrhage).
They have high intraluminal pressures, carry oxygenated blood and have pulsatile flow).
Elastic fibres are found in the walls of the largest, most proximal arteries e.g. the aorta.
Define sympathetic tone in relation to arterioles.
It is the background, low level of contraction of smooth muscle in arterioles and occurs due to tonic conduction of APs to arterioles via sympathetic nerves.
Describe how sympathetic axons reach all the bodies arterioles (body wall & organ’s arterioles) & define “thoracolumbar outflow.
Autonomic fibres descend from the brain to the lateral horn of the spinal cord. The sympathetic axons travel within the spinal nerve (anterior or posterior ramus) to the paravertebral ganglion of the sympathetic trunks to the arterioles. They pass into splanchnic nerves to eventually supply organs (preganglionc-postganglionic-target organ).
Thoracolumbar outflow is the travel of sympathetic nerves to sympathetic chains, running the length of the vertebral column.
Describe the aorta, including its “territory” .
All systemic blood enters the aorta first, received at high pressure during systole. Aorta’s walls expand under this pressure, but elastic recoil maintains peripheral flow during diastole.
Has 4 parts and many branches which supply the whole body.
List, in the order they arise, the branches of the ascending aorta, arch of the aorta, thoracic aorta and abdominal aorta.
- Ascending aorta:
- Left coronary artery.
- Right coronary artery. - Arch of the aorta:
- Brachiocephalic trunk (-> right subclavian & right carotid arteries).
- Carotid (left) artery.
- Subclavian (left) artery. - Thoracic aorta:
- Intercostal
- Bronchial
- Mediastinal
- Oesophageal
- Phrenic - Abdominal aorta:
- Coeliac trunk
- SMA
- IMA
+ Paired, bilateral:
- lumbar
- renal
- gonadal arteries
-> then bifurcates into L&R iliac arteries.
Describe the arterial blood supply to the brain .
Right and left common carotid arteries, divide into the external and internal carotids. Internal carotids form the circle of Willis.
Vertebral arteries pass through the transverse foraminae in cervical vertebrae, then the foramen magnum to enter the cranial cavity. These unite to form basilar artery.
Describe the carotid bifurcation.
Carotids bifurcate into internal and external carotids,
The carotid sinus is the most proximal part of the internal carotid artery, and innervated by CN IX. It senses blood pressure.
Define the “blood-brain barrier” and give examples of substances that can and cannot cross it.
Tight junctions exist between brain capillary and endothelial cells.
Astrocyte processes surround brain capillaries.
These combine to prevent diffusion of some substances from capillaries into the brain tissue, e.g. some antibiotics.
Ethanol, oxygen and CO2 are able to diffuse through.
BBB is weakened by brain injury, inflammation and neoplasia.
Explain and give examples of: anastomoses; collaterals; end arteries.
anastomoses: arteries connect with each other, without an intervening capillary network, e.g. Circle of Willis.
Collaterals: Each alternative route in any given anastomosis.
End arteries: the ONLY arterial blood supply to a given area of the body, i.e. no collaterals. E.g. coronary arteries, central artery of the retina.
Describe the bifurcation of the aorta and the body regions supplied by the resultant various “iliac” arteries..
abdominal aorta bifurcates into the common iliac arteries.
The common iliac arteries bifurcate into the left and right, External (lower limb supply) and Internal (pelvis/perineum supply) iliac arteries.
Name and state the approximate locations of the “peripheral pulses”.
Carotid pulse: posterior to, and at the level of the thyroid cartilage.
Brachial pulse: anterior to the elbow joint.
Radial pulse: radial side of the volar aspect of the wrist.
Femoral pulse: midpoint of the groin.
Popliteal: posterior to knee joint.
Posterior tibial: posterior to the medial malleolus of the tibia.
Dorsalis pedis: on the dorsum of the foot.
State and explain all the basic principles relating to veins.
Veins have merging tributaries, and drain territories. They carry low pressure venous blood. At rest, they contain approx. 60% of circulating blood volume.
They have a thin layer of smooth muscle in their walls, enabling them to contract, reducing venous capacity and returning blood to the arterial side of the circulation.
They often run in a neurovascular bundle, with arteries of the same name.
They are thin walled and collapsed when not full of blood.
They are non-pulsatile, with the exception of the jugular venous pulse.
Venous blood is pumped back towards the heart by: venous valves, the skeletal muscle pump and arterial pulsations.
Describe the skeletal muscle (venous) pump & venous valves and state their function.
Venous valves are present within limb veins, and ensure unidirectional flow of blood back to the heart against gravity.
The skeletal pump is formed by the contraction of skeletal muscles in the lower limb.
Define the superficial and deep venous systems.
Superficial veins are smaller, they run within superficial fascia and drain into deep veins. Deep veins are larger, and run deep to deep fascia in cavities, and often within NVB.
Define the systemic and the portal venous systems.
2 main venous systems of the body: hepatic portal (drains absorptive parts of GI tract & associated organs to the liver), and systemic (drains all other organs and tissues into the SVC or IVC).
Define the “circulatory system”.
Cardiovascular + lymphatic system.
Describe the function and basic anatomy of the lymphatic system .
Lymphatic system collect tissue fluid from capillaries, it then becomes lymph. Lymphatics carry lymph through lymph nodes containing WBCs to filter foreign particles and fight infection/cancer . Lymph is then returned to the central veins in the root of the neck.
The right lymphatic duct drains lymph into the right venous angle.
The thoracic duct drains lymph into the left venous angle.
What is palpation of a lymph node?
lymph nodes cannot usually be palpated. When fighting infection or being infiltrated by spreading cancer, they enlarge and can then be palpated.
