Anatomy + Physiology Flashcards
(184 cards)
1
Q
What are the 4 main things a cell contains?
A
Membrane
Cytoplasm
Mitochondria
Nucleus
2
Q
Tissue level of organisation
What are the 4 components of it?
A
Epithelia - cover exposed surfaces, line internal pathways + chambers + produce glandular secretions
Connective - fill internal spaces, provide support, store energy
Muscle - contracts for movement
Neural - conducts electrical impulses + carries info
3
Q
What is an organ?
A
A discrete collection of 2 or more tissues cooperatively performing a functions (heart, femur, biceps brachii muscle)
4
Q
Name and briefly describe the 11 key systems
A
- Integumentary - protection, sensation
- Skeletal - support, protection
- Muscular - tendons + ligaments = movement
- Nervous - communication
- Endocrine - regulate body processes
- Cardiovascular - distribute blood
- Lymphatic - coordinating a response
- Respiratory - movement of gases, speech
- Digestive - breaking down food = energy
- Urinary - excretion of waste
- Reproductive - formation of life
5
Q
What are the anatomical landmarks for the following areas?
- armpit, arm, forearm, wrist, hand
- thumb, big toe
- breast, chest
- head, nose, neck
- back, back of elbow, back of knee
A
Armpit = axilla
Arm = brachium
Forearm = antebrachium
Wrist = carpus
Hand = manus
Thumb = pollex
Big toe = hallux
Breast = mamma
Chest = thoracis
Head = cephalon
Nose = Nasus
Neck = cervicis
Back = dorsum
Of elbow = olecranon
Of knee = popliteus
6
Q
What is the anatomical position?
A
Standing
Facing forward
Feet together
Arms by sides
Hands supinated (palms forward)
7
Q
What are the directional terms for…
1. Closer / further from ORIGIN
2. Away / toward MIDLINE
3. Top / bottom
4. At head / at tail
5. Front / back (2)
A
- Proximal OR Distal
- Lateral OR Medial
- Superior OR Inferior
- Cranial OR Caudal
- Ventral/Anterior OR Dorsal/ Posterior
8
Q
What are the 2 terms associated with imaging of a body?
A
Superficial (at surface) and deep (inside body)
9
Q
What are the 3 planes?
A
Frontal = front + back sections - splits posterior + anterior sections
Sagittal = separates left + right
Transverse = top + bottom sections - horizontal in anatomical position
10
Q
What are the 2 main body cavities + describe them
A
- Dorsal cavity = brain + spinal cord
- Ventral cavity = thoracic, abdominal + pelvic organs
- thoracic cavity = pleural (around lungs) + pericardial cavity (around heart) = organs move smoothly past each other
- abdominopelvic cavity = peritoneal cavity, abdominal + pelvic cavity (digestive organs)
11
Q
What is homeostasis + the 2 types of feedback?
A
Maintenance of a constant internal environment
- negative feedback opposes variations from normal e.g. thermoregulation
- positive feedback exaggerates variations e.g. blood clotting
12
Q
What are the main roles of the nervous system + what are they performed by?
A
- Monitors the internal + external environments (via thermo, chemo, baro, photoreceptors)
- Integrates sensory information
- Coordinates voluntary + involuntary responses of many organ systems
- performed by neurons and supported by neuroglia
13
Q
Name and describe the 2 anatomical subdivisions of nervous system
A
CNS = central nervous system
- brain + spinal cord
- integrates + coordinates processing of sensory data + transmission of motor commands
- coordinates higher functions
PNS = peripheral nervous system
- includes all neural tissue outside of CNS
- delivers sensory information to CNS
- carries motor commands to peripheral tissues + systems
14
Q
What are the 4 different types of neurons?
A
Anaxonic
Bipolar
Unipolar
Multipolar
15
Q
What is an anaxonic neuron?
A
- found in brain + special sense organs
- very small
- no anatomical features that distinguish dendrites from axon (no axon)
- Functions poorly understood
16
Q
What is a bipolar neuron?
A
- have 2 processes - 1 dendrite and 1 axon with the cell body between them
- rare as only occur in special sense organs
17
Q
What is a unipolar neuron?
A
- dendrites + axon are continuous with cell body lying off to one side
- found in most sensory neurons of PNS
18
Q
What is a multipolar neuron?
A
- has 2 or more dendrites + a single axon
- most common neurons in CNS
- all motor neurons that control skeletal muscles are multipolar
19
Q
What are the 2 main roles of the spinal cord?
A
- major passageway of sensory + motor impulses to/from brain
- integrates info on its own + controls spinal reflexes + automatic motor responses
20
Q
Describe the rough outline of a spinal cord
A
- 31 segments (8 cervical, 12 thoracic, 5 lumbar, 5 sacral + 1 coccygeal)
- each segment contains a pair of dorsal root ganglia containing cell bodies of sensory neurons
- dorsal roots bring sensory info to spinal cord
21
Q
What do ventral roots contain in spinal cord?
A
Axons of motor neurons
22
Q
What do the following parts contain in a spinal cord…
- gray matter
- white matter
A
- contains cell bodies + neuroglia cells
- myelinated + unmyelinated axons
23
Q
What is a dermatome?
A
Specific region of a body surface relating to the parts of the body that spinal nerves monitor
24
Q
Explain the 5 steps regarding a reflex arc
A
- Arrival of stimulus + activation of stimulus
- Activation of sensory neuron
- Info processing in CNS
- Activation of motor neuron
- Response by peripheral effector
25
What is the role of Golgi tendon organs?
Senses tension in tendons when a muscle contracts
- has an inhibitive (negative) afferent neuron
- when excessively large forces are generated, feedback from these causes activation of muscle to decrease = PROTECTIVE
26
What are muscle spindles + what do they do?
Highly specialised encapsulated muscle fibres parallel to normal muscle fibres
- sensitive to changes in length
- afferent neuron wraps around muscle spindle
- efferent neuron (gamma) causes muscle spindles to contract to maintain tension in middle of fibres
- if muscle is stretching rapidly - vigorous contraction to prevent overstretching
27
Name and briefly describe the 6 key regions of the brain
Cerebrum - conscious thought processes, memory storage + regulation of skeletal muscle contractions
Diencephalon - contains thalamus (relay + processing centre for sensory information) + hypothalamus (controls emotions, autonomic functions + hormone production)
Midbrain - processes visual + auditory info, generates reflexive isolation motor responses
Pons - relays sensory info to cerebellum + thalamus
Medulla Oblongata - relay sensory info to thalamus + brain stem + regulation of visceral function
Cerebellum - coordinates complex somatic motor patterns
28
What’s are the 2 types of brain protection?
(Physical)
- bones of cranium
- cranial meninges
- cerebrospinal fluid
(Biochemical)
- blood-brain barrier
29
Explain how cranial meninges + cerebrospinal fluid help to protect the brain
Cranial meninges:
- 3 layers = dura matar, arachnoid matar, pia matar
- continuous with spinal meninges = protects brain from trauma
Cerebrospinal fluid:
- surrounds all exposed surfaces of CNS
- interchanges with interstitial fluid of brain
- cushions, supports + transports nutrients, chemical messengers + waste products
30
List the 12 cranial nerves
I. Olfactory - smell
II. Optic - vision
III. Occulomotor - eye position during movement
IV. Trochlear - movement of eyes superior oblique muscle
V. Trigeminal - sensory innervation to face
VI. Abducens - abduction of eye to look sideways
VII. Facial - motor innervation to facial muscles
VIII. Vestibulocochlear - hearing, balance
XI. Glossopharyngeal - sensory info to mouth + throat
X. Vagus - heart rate, digestion
XI. Accessory - motor info to sternocleidomastoid + trapezius
XII. Hypoglossal - tongue movement
31
What is the resting membrane potential - what’s on the outside/ inside etc?
-70mV resting potential
This means there is an excess of +ive charged on the outside (Na+ and Cl-) and -ive charged on inside (K+ and Pr-)
32
What is the word to describe the resting cell membrane?
Polarised
33
What does it mean by selective permeability of cell membranes?
Ions can enter/leave the cell with help from channels/ carrier proteins
- leak channels (always open) are more permeable to K+
- gated channels (open/close depending on circumstances)
34
Describe the passive movement of ions across cell membranes
1. K+ move out of the cell and Na+ move into the cell (K+ move out faster)
- the +ively charged outer membrane surface repels K+ ions
2. At the same time -ively charged inner membrane attracts Na+
- the chemical gradient is stronger than electrical repelling force so K+ still move out
3. Therefore there is a net loss of +ive ions
- 3 Na+ for every 2K+
35
What causes changes to membrane potential?
Any stimulus that…
- alters membrane permeability to Na+ or K+
- alters the activity of exchange pump
…will disturb the resting potential
36
Describe an overview of how chemically gated ion channels work to disturb the resting potential
1. The opening of gated Na+ channels increases Na+ entry into the cell
2. As the number of +ive charged ions increase on inner surface, the membrane potential shifts towards 0mV
3. This is called depolarisation
4. When the stimulus is removed, repolarisation occurs to restore the resting membrane potential
37
What is hyperpolarisation?
When the membrane potential exceeds -70mV
- could be due to opening of gated K+ channels so more K+ leave the cell = more negative inside
38
What are the 3 main types of gated channels?
Chemically gated = ions
Voltage gated = charges inside/ outside cell
Mechanically gated = pressure
39
What are graded potentials?
Also called local potentials
- they only affect a limited portion of the cell membrane + cannot spread far from site of replication
40
Describe the 3 steps involved in graded potentials
1. Resting membrane is exposed to chemicals
- Na+ channels open so Na+ enter into cell
- membrane potential rises and depolarisation occurs
2. Movement of Na+ through channel produces a local current
- this depolarises nearby cell membrane
3. When stimulus is removed, repolarisation occurs
41
What are action potentials?
An electrical signal that affects the entire membrane surface
- skeletal muscle fibres + axons have excitable membranes that will conduct action potentials
42
What must occur for an action potential to be generated?
The membrane must depolarises sufficiently to a level known as the threshold
= all or none principle
43
Describe the 4 steps involved in generating an action potential
1. The membrane is depolarised and exceeds the threshold of -60mV
2. Na+ channels are activated and rapid depolarisation occurs (+10mV)
3. Inactivation of Na+ channels and activation of K+ channels (as potential reaches +30mV)
4. Brief hyperpolarisation + return to normal permeability and resting state
(2-3) absolute refractory period = membrane cannot respond to further stimulation
(4) relative refractory period = membrane can respond but only to larger than normal stimuli
44
Describe the 4 steps involved in propagating an action potential
1. AP in segment 1 depolarises membrane to +30mV
2. Local current whereby Na+ spread away from channel = depolarisation of segment 2 to threshold
3. Second segment develops an AP (first segment in refractory period)
4. Local current depolarises next segment + cycle repeats
45
What are myelinated axons?
Axon is wrapped in layers of myelin except at nodes
- oligodendrocytes = bundles of much smaller cells around
- Schwann cells = one cell wraps around
46
What is saltatory propagation?
Continuous propagation cannot occur as depolarisation only occurs at nodes
- an AP jumps from node to node = much faster than continuous propagation
47
Describe the 4 steps involved in saltatory propagation
1. An AP occurs at initial segment
2. Local current produces a graded depolarisation that brings the axolemma at next node to threshold
3. An AP develops at node 2
4. Local current produces a graded depolarisation that brings the axolemma at next node to threshold
48
What is a synapse + how do info transfer occur?
The site of communication between a nerve cell and some other cell
- info transfer occurs through release of neurotransmitters from synaptic terminal
- occurs in 1 direction
49
What are the 2 kinds of effects neurotransmitters can have?
Excitatory = causes depolarisation of postsynaptic membrane + promote APs
Inhibitory = causes hyperpolarisation of post synaptic membranes = suppresses APs
50
What neurotransmitter is released at cholinergic synapses?
Acetylcholine
51
Describe the steps that occur at cholinergic synapses
1. An arriving AP depolarises the axon terminal of a presynaptic neuron
2. Ca2+ enter the cytosol of the axon terminal = results in ACh release from the synaptic vesicles by exocytosis
3. ACh diffuses across the synaptic cleft + binds to receptors on the postsynaptic membrane. (Sodium channels open producing a graded depolarisation)
4. Depolarisation ends as ACh is broken down into acetate and choline by AChE - axon terminal reabsorbs choline from the synaptic cleft and uses it to resynthesise ACh
52
Aside from acetylcholine, what are the other 4 important neurotransmitters?
Norepinephrine/ noradrenaline = excitatory effect, released by adrenergic synapses
Dopamine = in CNS, both excitatory/ inhibitory effects
Serotonin = regulation of sleep/wake cycle, lack of serotonin = depression
GABA = inhibitory effect to reduce anxiety
53
What is the function of epithelial tissues?
Layers of cells that form linings of membranes + glands
54
What are the 2 types of layers of epithelial cells and what are the 4 types of shapes of epithelial cells?
Layers:
- simple = 1 layer
- stratified = many layers
Shape:
- squamous = flat
- cuboidal = cube shaped
- columnar = rectangle
- transitional = can change shape
55
What is the function of simple and stratified squamous epithelial tissues?
Simple squamous = linings of blood vessels + alveoli
- to reduce friction, assist in absorption + secretion (flat so short diffusion distance)
Stratified squamous = skin
- provides physical protection (lots of cells) against abrasion, pathogens + chemical attack
56
What is the function of simple and stratified cuboidal epithelial tissues?
Simple cuboidal = glands, ducts (kidney tubule)
- limited protection but good for secretion + absorption
Stratified cuboidal = linings of some ducts (rare) - sweat glands
- protection, secretion, absorption
57
What is the function of simple and stratified columnar epithelial tissues?
Simple columnar = lining of stomach + intestine
- protection, secretion , absorption
- likely to have microvilli on apical (top) surface
Stratified columnar = small areas of pharynx
- protection
58
What is the function of transitional epithelial tissues?
Primarily found in the urinary bladder
- permits expansion + recoil after stretching
59
What is the other kind of columnar epithelial tissue, and what is its role?
Pseudostratified Ciliated Columnar = lining of nasal cavity, trachea + bronchi
- for protection, secretion, move mucus with cilia on apical surface
60
How are glands classified?
According to shape - tubular, coiled, branched, alveolar
And…
Number of ducts - simple (one) and compound (many)
61
What are the 3 kinds of glandular secretion?
Merocrine = cell remains intact + release microscopic bubbles
Apocrine = substance accumulates in apical surface of the cell + when secreted the apical portion breaks down + has to be reformed
Holocrine = stratified - cell bursts + releases contents
62
What are the 3 main things connective tissues contain?
Cells e.g. fibroblasts (produces protein fibres), adipocytes (fat cell) and macrophages (immune cell)
Fibres e.g. collagen, reticular, elastic
Ground substance e.g. fluid (blood + lymph), gel (cartilage), mineral (bone)
63
What are the first kind of connective tissues to appear in embryos?
Mesenchymal stem cells = partly differentiated cell that can differentiate into other types of connective tissue
64
What makes up the blood?
Red + white blood cells
Platelets
Both in the fluid / plasma of the blood
65
What are the 2 types of loose connective tissues - explain where they’re found + their role
Adipose tissue = deep to the skin (at sides, buttocks, breasts, padding around eyes + kidneys)
- provides padding + cushions shocks, insulates + stores energy
Reticular tissue = around the liver, kidney, spleen, lymph nodes, bone marrow
- provides a supporting network
66
What are the 3 kinds of dense connective tissues - explain where they’re found + their role
Dense regular = between skeletal muscles + skeleton (tendons) + between bones (ligaments)
- provides firm attachment, conducts pull of muscles
Dense irregular = capsules of visceral organs, nerve + muscle sheaths
- provides strength to resist forces applied from many directions + helps prevent over expansion of muscles
Elastic tissue = between vertebrae of spinal column + in blood vessel walls
- stabilises, cushions shocks, allows expansion + contraction
67
Wheat are the 3 types of cartilage?
Hyaline cartilage = between tips of ribs + bones of sternum, covering bone surfaces at synovial joints
- provides stiff but somewhat flexible support + reduces friction
Elastic cartilage = auricle of external ear
- provides support but tolerates distortion without damage + can return to original shape
Fibrocartilage = pads within knee joint
- resists compression, prevents bone-to-bone contact, limits movement
68
What are the 4 types of tissue membranes - explain their role + what type of epithelium they have
1. Mucous membrane = simple columnar epithelium
- coated with secretions of mucous glands
2. Serous membrane = simple squamous epithlium
- lines the ventral body cavities
3. Cutaneous membrane = stratified squamous + cuboidal epithelium
- covers body surface
4. Synovial membrane
- lines joint cavities + produces fluids within a joint
69
What’s the different layers of the fasciae?
Superficial fascia = between skin + underlying organs
- made up of areolar + adipose tissues
Deep fascia = forms a strong, fibrous internal framework
- made up of dense connective tissue
Subserous fascia = between serous membranes + deep fascia
- made up of areolar tissue
70
What are the 3 types of muscle tissue?
Skeletal muscle - under voluntary control
- striated + multinucleated
- controlled via nerves
Cardiac muscle - under involuntary control
- striated
- controlled by pacemaker cells
- intercalated disks allows electrical connections
Smooth muscle - under involuntary control
- not striated
- hormonal control
71
What are the main functions of the skeletal system?
- supports against gravity
- leverage for muscle action
- protection for soft internal organs
- storage
- blood cell production
72
What are the 6 shapes of bones (4 key ones)?
Flat bones - internal + external table separated by diploe (parietal bone)
Long bones - longer than they are wide (humerus)
Short bones - Same width as length (carpals, tarsals)
Irregular bones - complex shapes (vertebrae)
Sutural bones - between skull bones
Sesamoid bones - small + develop in tendons
73
What are the typical features of long bones?
Diaphysis (shaft) - compact dense bone + medullary cavity
Epiphysis (end/ articulating surface) - trabecular spongy bones
Articulating cartilage
74
What is the bone (osseous) tissue made up of?
1. Ground substance - 2/3 of bone matrix
- contains minerals, predominantly crystals of hydroxyapatite
2. Protein - 1/3 of bone matrix
- mainly type 1 collagen fibres
3. Bone cells - 2% of bone mass
- mesenchymal stem cells differentiate into osteoblasts (bone ‘builder’) and then osteocytes
- osteoclasts = bone ‘crusher’ (old bone)
75
What are osteoblasts, osteocytes + osteoclasts - what they do
Osteoblasts = immature bone cell that secretes matrix proteins
Osteocytes = mature bone cell that maintains the bone matrix
Osteoclasts = multinucleated cell that secretes acids + enzymes to dissolve bone matrix
76
What is the structure of compact bone (tibia)?
It has many repeating units of osteons
- these are a basic functional unit that creates columns
Has a central canal = allows a blood supply so calcium can be transported to bone
Has a lamellae + a lacunae (contains osteocytes)
77
What are the features of trabecular (spongy) bone?
No osteons
1. Trabeculae
- consist of arches, rods + plates of bone = branching network
2. Red marrow
- between trabeculae which forms red blood cells to provide nutrients to osteocytes
3. Yellow marrow
- found in the medullary cavity which stores fat
78
What is the periosteum?
The membrane outside the bone = fibrous + cellular layer
- collagen fibres continuous with bone, ligaments, tendons + joint capsule
- also contains lymphatic vessels + nerves
79
What is the endosteum?
Another membrane lining the bone
- incomplete cellular layer
Lines the medullary cavity, central canals, trabeculae
80
What is the term used to describe bone formation + growth?
Ossification - formation of/ conversion into bone
81
What are the 3 types of bone growth?
Intramembraneous ossification
- flat bone formation
Endochondral ossification
- formation from cartilage model
Appositional bone growth
- growth in width
82
Describe intramembraneous ossification
- Mesenchymal cells differentiate into osteoblasts
- Ossification forms spicules of bone
- Trabecular bone formed
- Remodeled into compact bone
83
Describe endochrondal ossification
1. Chondrocytes within calcifying matrix enlarge then die
2. Osteoblasts cover shaft in a thin layer of bone
3. Blood vessels + osteoblasts penetrate to form a primary ossification centre (diaphysis)
4. Primary ossification centre enlarges (only centre of bone formed)
5. Secondary ossification centres form at epiphyses (ends of bone formed)
- Separated by epiphyseal cartilage (growth plate)
- Hormonal changes triggers fusion of epiphyseal cartilage
84
Describe appositional bone growth
Bone is deposited by osteoblasts = bone inside is resorbed
85
What are the requirements for normal bone growth?
Minerals - calcium, phosphate
Vitamins - vit D3 and others
Hormones - growth hormone, sex hormones, thyroid hormones etc
Loading
86
What hormones control calcium storage/ release?
PTH stimulates bone resorption to release calcium
Calcitonin stimulates bone formation to store calcium
87
How is bone mineral density measured?
- when is peak bone mass + when is bone loss most rapid?
Measured via a DXA (dual x-ray absorptiometry) scanner
- peak bone mass usually in 30s
- bone loss from 40s is most rapid after menopause (females)
- may result in osteoporosis
88
What are the 4 steps involved in fracture repair?
1. Bleeding and formation of clot (fracture haematoma)
2. Formation of external callus (cartilage) and internal callus (spongy bone)
3. External callus replaced by bone (compact) + internal callus unites broken ends
4. Initial swelling eventually remodelled
89
What are the 2 divisions of the skeleton?
Axial skeleton and the appendicular skeleton
90
What components are within the axial skeleton?
Skull + associated bones
Thoracic cage
Vertebral column
91
What components are within the appendicular skeleton?
Pectoral girdle
Upper limbs
Pelvic girdle
Lower limbs
92
What are the bones that make up the entire cranium?
Frontal bone = forehead, superior surface of orbits
Parietal bones = sides/ roof
Temporal bones = sides/ base - contain structure of inner ear
Occipital bones = foremen magnum - passageway for spinal cord
Sphenoid bone = bridge between cranial and facial bones
Ethmoid bone = cribriform plate (small holes for nerves to go through) + naval septum
93
What are the functions of facial bones?
Supports cavities + sense organs
Attachment of muscles/ structures for mastication (chewing), speech and facial expressions
Protection
94
What are the 6 bones that make up the facial bones?
Maxillary bones - under the eyes + around nose
Zygomatic bones - cheek bones (forms zygomatic arch with temporal bones)
Mandible - lower jaw bone
Nasal bones - bridge of nose
Nasal septum - part of ethmoid bone + tracks foreign objects breathed in
Paranasal sinuses - air filled cavities lined with mucus membranes
95
What are bones separated by when we are born?
Sutures - these are flexible so allow growth at edges
96
Describe the structure of the vertebral column
26 bones - 7 cervical, 12 thoracic, 5 lumbar, sacrum + coccyx
- Cervical = oval body, transverse foramina, bifid/ split spinous process (C1 = atlas and C2 = axis)
- thoracic = heart shaped body, facets for articulation with ribs, long inferiorly directed spinous process, dimples
- lumbar = massive (to support loading), no facets, blade like transverse process
- sacrum = 4-5 vertebra are fused = makes up pelvis
As you move down the column = heavier vertebrae + foremen gets smaller
97
What are following parts of the vertebral column for?
- body, arch, spinous process, transverse process, articular process
Body = weight bearing, articulate with bodies above
Arch = consists of pedicel + laminar, surrounds transverse + spinous process as well as vertebral foramen = protection
Spinous + transverse process = muscle attachment
Articular process = articular facets which articulate with vertebrae above/ below
98
What are the components of the thoracic cage?
Sternum
Ribs - 7 pairs of true ribs + 5 pairs of false ribs
99
What’s the function of the thoracic cage?
- protects thoracic contents
- allows expansion + contraction for ventilation
100
Describe the structure of ribs and what they articulate with
It is a curved flat bone
- head articulates with vertebral body
- tubercle articulates with transverse process of vertebra
- costal cartilages articulates with sternum
101
What does the word girdle mean?
It is a ring of bone
102
What’s the function of the pectoral girdle?
Enables versatile movement
Allows articulation for arm
103
What are the components of the pectoral girdle?
clavicle (acromial + sternal ends) - contains facets for articulation
scapulae (shoulder blade)
- acromion
- scapular spine
- glenoid cavity
104
List the bones of the upper limbs
Humerus
Radius + ulna
Carpals (2 rows) + metacarpals
Phalanges
105
What parts of the humerus articulates with what?
The head articulates with the scapula
Distal condyles articulate with the forearm
Also many other sites of muscle attachment
106
What parts of the radius and ulna articulates with what?
Radius:
- lateral (thumb side)
- head articulates with humerus
- distal end participates in wrist joint
Ulna:
- trochlear notch articulates with humerus
- olecranon forms point of elbow
107
What parts of the wrist + hand articulate with what?
2 rows of carpal bones:
- proximal row articulates with radius
- distal row articulates with metacarpals
Metacarpals:
- support palm (numbered I - V)
- I = thumb
Phalanges:
- articulate with metacarpals
108
What are the functions of the pelvic girdle?
Support
Articulation of the leg
109
What does the pelvic girdle consist of?
Os Coxae
Sacrum
Coccyx
110
What is the Os Coxae?
The coxal bone is formed by the fusion of…
- ilium
- ischium
- pubis
Key features = iliac crest, acetabulum (articulates with femur), ischial tuberosities
111
How is the pelvic girdle of women adapted for childbirth over men?
Wider pubic angle - more than 90 degrees
112
What are the key bones of the lower limbs?
Femur
Tibia + fibula
Tarsals + Metatarsals
Phalanges + hallux
113
What parts of the femur functions in what?
Head = forms balls + socket joint
Neck = allows stable weight bearing
Greater trochanter = muscles attach here
Shaft
Condyles = articulating surfaces at distal end = forms part of knee
114
Describe the features of the tibia + fibula
Tibia:
- the thicker bone of the 2
- forms condyles that make up knee
- articulates with femur
- distal articular surface (medial malleolus) = ankle joint
Fibula:
- head articulates with tibia
- distal articular surface (lateral malleolus) = ankle joint
115
What are the bones in the ankle?
7 talus bones which include…
1. Talus = joint with the tibia + fibula
2. Calcaneus (heel bone) = major load bearing bone
116
What are the bones in the foot?
Metatarsal bones - numbered I to V
Phalanges + hallux (big toe)
117
What are the 2 functions + 2 classifications of joints?
Functions:
- allowing movement
- stability
Classification
- functional - amount of movement
- structural - composition of joint structures
118
What are the 3 types of functional joints?
- Synarthrosis = immovable joint with close/interlocked surfaces joined with fibres, cartilage or bone
- Amphiarthrosis = slightly moveable joint with surfaces connected by collagen fibres/ cartilage
- Diarthrosis (synovial) = freely moveable joint
119
What are the 4 kinds of structural joints?
1. Bony joints
2. Fibrous joints
3. Cartilaginous joints
4. Synovial joints
120
Describe bony joints
Synostosis (synarthrosis) = 2 bones have become fused together
- e.g. joint between left and right frontal bone
121
Describe fibrous joints
Suture (synarthrosis) = articulating bones interlock + attach by collagen fibers
- e.g. sutures in cranium
Gomphosis (synarthrosis) = tooth fits in a socket attached by a ligament
- e.g. joints between teeth and jaws
Syndesmosis (amphiarthrosis) = bones connected by ligament
- e.g. joint between tibia + fibula
122
Describe cartilaginous joints
Synchondrosis (synarthrosis) = bones connected by cartilage
- e.g. costal cartilage
Symphysis (amphiarthrosis) = bones separated by fibrocartilage disk
- e.g. pubic symphysis
123
Describe synovial joints
Synovial (diarthrosis) = cartilage, synovial fluid, joint capsule
- e.g. found at ends of long bones (knee)
124
What are the 6 different synovial joints?
1. Gliding – slight movement e.g. claviculo-sternal
2. Hinge – monoaxial movement e.g. elbow
3. Pivot – monoaxial (rotation) e.g. atlanto-axial
4. Condylar – biaxial (flexion/extension + abduction/adduction) e.g. radiocarpal
5. Saddle – biaxial e.g. first carpo-metacarpal (base of thumb)
6. Ball & socket – triaxial e.g. shoulder
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What are the factors affecting synovial joint function?
Joint + accessory structures
Tendons + muscles crossing joint
Other bones, muscles, fat pads which can limit movement
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What are all the kinds of joint movements?
Flexion / extension
Abduction / adduction
Circumduction
Rotation
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Describe flexion / extension - plane + what it is
Angular movement in the Sagittal plane
- flexion = reducing angle
- extension = increasing angle
- hyperextension = past anatomical position
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Describe abduction / adduction - plane + what it is
Angular motion in frontal plane
- abduction = away from longitudinal axis
- adduction = towards longitudinal axis
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Describe circumduction
Circular motion without rotation
- combination of flexion/extension + abduction/adduction
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Describe rotation - plane + what is it
Motion around longitudinal axis
- left or right rotation
- medial or lateral rotation
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What is rotation of the forearm?
Pronation = radius crosses over ulna
- turns palm to face posteriorly
Supination = to anatomical position
- turns palm to face anteriorly
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What are the 4 special movements of the foot?
Inversion = twist sole medially
Eversion = twist sole laterally
Dorsi flexion = flexion at ankle + raise toes
Plantar flexion = extension at ankle + pointing of toes
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What are the key components of intervertebral discs?
Fibrocatilage pads - symphyses joint
Annulus fibrosis - outer fibrous layer
Nucleus pulposes - elastic core
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What happens if there is damage to intervertebral discs?
The nucleus pulposes releases + bulges out
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Describe the shoulder joint - joint capsule, type etc
Glenohumeral joint
- relatively loose joint capsule = optimised for joint movement
- easily injured as less stable
- synovial ball and socket joint
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Describe the hip joint - joint capsule, type of joint etc
Coxal joint
- stronger + thicker joint capsule
- reinforced by more ligaments
- less movement but more stable
- synovial ball + socket
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What parts of hip joint articulates with what?
1. Head of femur articulates with deep acetabulum
2. Acetabular labrum deepens cavity
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Describe the elbow joint - joint capsule, type of joint etc
Synovial hinge joint
Humeroradial - pronation + supination
- capitulum with head of radius
Humeroulnar - flexion + extension
- trochlear with trochlear notch of ulnar
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Describe the knee joint - joint capsule, type of joint etc
Complex hinge joint
- meniscus = contains movement of condyle
- patellar ligament = attaches patellar to tibia
- anterior + posterior cruciate ligament = limits movement of tibia forward + back relative to femur
- tibial + fibula collateral ligaments (on side) = stability from side to side + loose when bend knee
- fibula does not articulate at knee
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What are the 3 key joint injuries?
Sprain - tearing of ligament fibres
Dislocation (luxation) - articulating surfaces displaced (damages articular cartilage, ligaments, joint capsule)
Subluxation - partial dislocation
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What are the 3 key joint diseases?
Osteoarthritis
- damage to articular cartilage + underlying bone (with age, obesity + injury)
Rheumatoid arthritis
- autoimmune condition
- inflammation of articular cartilage
Gouty arthiritis
- deposition of crystals in a joint as a result of metabolic disorder
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Go through the list (largest to smallest) of the entire muscle structure
- Fascicle = bundles that make up the whole muscle
- these are enveloped in epimysium (deep fascia) + perimysium between each bundle
- each bundle contains a bundle of muscle fibres which are enveloped by endomysium
- myofibrils within each muscle fibre - sarcolemma around muscle fibre with sarcoplasm between each myofibril
- myofibrils made of many sarcomeres
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What are the 2 filament proteins on sarcomeres
Thin filament = actin
- double helical strands
- tropomyosin acts with actin + covers binding sites where thick filament can binds
- troponin = other protein on actin
Thick filament = myosin
- globular head + flexible region head + tail
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What are the other 3 structural proteins involved with sarcomeres?
1. Titin - acts like a spring to return sarcomere to original resting state
2. Nebulin = ‘scaffolding’ holding everything together - mainly actin
3. Desmin = ‘scaffolding’ of Z lines
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What is the sarcoplasmic reticulum?
Interconnecting tubules surrounding myofibrils
It regulates intracellular levels of calcium
- stores calcium + releases on stimulation to allow contraction
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Describe the cross-bridge cycle [8]
1. Action potential arrives
2. Ca2+ gets released from sarcoplasmic reticulum
3. Ca attaches to troponin
4. Tropomyosin moves uncovering myosin binding sites on actin
5. Hydrolysis of ATP changes angle of myosin head = crossbridge formed
6. Pi is released from myosin head changing angle of myosin head = power stroke
7. Myosin head picks up another ATP and bond with actin is released
8. Repeats until Ca2+ or ATP level drop
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What is the appearance, energy source + mitochondrial density of the following fibre types?
- Type 1 (SO)
- Type 2a (FTO)
- Type 2x (FTG)
Type 1 = red, fat, high
Type 2a = pink, fat/glycogen, intermediate
Type 2b = white, glycogen/ PCR, low
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Describe the neuromuscular junction
Where motor neurone meets muscle fibre
- motor end plate = pocket formed around motor neurone by sarcolemma
- synaptic cleft = small gap between neuron + motor end plate
- acetylcholine = release from motor neurone resulting in depolarisation of motor end plate
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Describe the process of an action potential arriving at neuromuscular junction
1. Axon terminal is depolarised
2. Calcium influx into axon terminal
3. Encourages release of acetylcholine into synaptic cleft
4. Acetylcholine interacts with the sodium ion channels on the post synaptic membrane
5. Sodium ion channels open and sodium influx causes depolarisation
6. As the charge of the muscle cell membrane increases, voltage gated calcium channels open and there is a calcium influx
7. The increase in charge also stimulates calcium release from the sarcoplasmic reticulum
8. When the action potential ceases the acetylcholine re-enters the neuron as choline and acetic acid
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What are the 2 neurones that control skeletal muscle?
1. Efferent neurone = neuron’s that send impulses from CNS to limbs + organs (muscles)
2. Afferent neurone = neurone that carry nerve impulses from sensory receptors towards CNS
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What are the 6 general senses?
Temperature
Pain
Touch
Pressure
Vibration
Proprioception
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What are the 5 special senses?
Vision
Hearing
Taste
Balance (equilibrium)
Smell
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What happens when light enters the eye?
It is refracted by the cornea + lens and focused onto the retina
Light is then absorbed at retina by photoreceptors
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What are the 2 photoreceptors in eyes - what do they do and what are the pigments associated with them?
Cones predominate in central vision + lighter environments and rods predominate in periphery vision + in darker environments
- light interacts with photopigments e.g. rhodopsin (Opsin + retinal)
- in presence of light, rhodopsin splits altering flow of electrical current
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Describe the visual pathway from optic nerves
1. 2 optic nerves reach diencephalon in brain at optic chiasm
2. Here half of the nerve fibres from each eye cross over to reach thalamus on opposite side of brain
3. Nuclei in thalamus relay visual info to reflex centres in brain stem + to the visual cortex of cerebrum
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Where are the senses for both hearing and equilibrium provided?
The inner ear
- receptor complex located in temporal bone of skull
- receptors (hair cells) are simple mechanoreceptors
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Describe the structure of the middle ear
It is an air filled cavity
Separated from ear canal by tympanic membrane
Contains auditory ossicles - malleus, incus, stapes
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Describe the structure of the inner ear
Receptors for hearing + balance lie within membranous labyrinth of cochlear ducts (in cochlea)
- contains 2 types of fluid = endolymph + perilymph
Cochlear duct is sandwiched between a pair of perilymph filled chambers
Bony labyrinth walls are dense bones except at 2 areas:
- round window - base of tympanic duct
- oval window - base of vestibular duct
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What is the organ of corti - where is it located + what do it contain?
Sits above the basilar membrane in inner ear
- contains hair cells of cochlear ducts
- stereocilia of hair cells in contact with tectorial membrane
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Describe the process of hearing [6]
1. Sound waves arrive at tympanic membrane
2. Movement of membrane causes displacement of auditory ossicles
3. Movement of stapes at oval window establishes pressure waves in perilymph of vestibular duct
4. Pressure waves distort the basilar membrane on way round to round window
5. Vibration of basilar membrane causes vibration of hair cells against tectorial membrane
6. Info about region + intensity of stimulation is relayed to CNS over cochlear branch of cranial nerve VIII
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What are equilibrium sensations specifically provided by?
Hair cells of vestibular apparatus = semi-circular canals + otoliths
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Describe what semi-circular canals and otoliths are
Semi-circular canals:
- receptors respond to rotational movements (hair cells located in ampulla)
- Crista is a raised structure in ampulla - connects to sensory nerve
- stereocilia are embedded in cupula
Otoliths:
- utricle which detects horizontal linear accelerations
- saccule which detects vertical linear accelerations / gravity
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Describe the equilibrium pathways
Sensory neurones monitor hair cells of otoliths + semi-circular canals and afferent fibres form vestibular branch of vestibulocochlear nerve
The fibres synapse on neurones in vestibular nuclei with 4 main roles:
1. Integrate sensory info arriving from each side
2. Relay info to cerebellum
3. Relay info to cerebral cortex
4. Send commands to motor nuclei in brain stem + spinal cord
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What allows us to taste things - receptors?
Gustatory receptors located on the superior surface of the tongue + adjacent to pharynx + larynx
We also have taste buds which are specialised epithelial cells that lie along epithelial projections called papillae (3 types)
1. Filiform (no taste buds)
2. Fungiform (roughly 5)
3. Circumvallate (roughly 100)
- each taste bud contains gustatory cells (sensory receptors) + supporting cells
- the gustatory cells extend microvilli into surrounding fluids via taste pore
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What are the 6 taste sensations?
Bitter
Sweet
Sour
Salty
Umami
Water
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What are taste buds monitored by?
3 cranial nerves - facial, glossopharyngeal, vagus
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Describe the process of detecting smell (olfaction)
Provided by paired olfactory organs (nasal cavity) = olfactory epithelium + glands
1. When breathing in, air swirls in the nasal cavity
2. Reaches olfactory organs and lipid + water-soluble chemicals diffuse into mucus – then stimulates olfactory receptors
3. (cilia attached to each receptor cell extends into mucus) - dissolved chemicals interact with odorant binding proteins on cilia surfaces
4. (odorants = chemicals that stimulate olfactory receptors) - binding of odorants changes permeability of receptor membrane = APs
5. Info is relayed to CNS + smell is interpretated
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What are the smell pathways?
Bundles of axons penetrate the cribriform plate of ethmoid bone + olfactory bulb
Axons leaving each bulb travel along olfactory tract to olfactory cortex of cerebrum, hypothalamus + portions of limbic system
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What are the components + functions of the integumentary system?
Components:
- cutaneous membrane
- accessory structures
Functions:
- protection + excretions
- maintenance of body temp
- production of melanin + keratin
- synthesis of vitamin D
- sensation - touch, pressure, pain, temp
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Describe the organisation of the skin
Epidermis = most superficial layer - contains epithelial tissues with basement membrane
- stratified squamous epithelium
Dermis = thicker + stronger layer underneath
Hypodermis = has connective tissues
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Describe the following parts of the epidermis…
- stratum basal (5)
- stratum spinosum (4)
- stratum granulosum (3)
- stratum lucidum (2)
- stratum corneum (1)
- stratum basal = where basal keratinocytes divide
- stratum spinosum = daughter cells move further away from dermis with blood supply = start to get dehydrated + shrunken
- stratum granulosum = keratin is produced + cells start apoptosis
- stratum lucidum = see-through due to flattened clear cells (only in thick skin)
- stratum corneum = contains dead, flat keratinocytes lacking organelles
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What is EGF - epidermal growth factor?
It stimulates cell division, keratin production + glandular secretion
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What colours do the following skin pigments produce + any other roles?
Carotene, melanin, blood
Carotene = yellowish
Melanin = brown
- protects from UV radiation
- contributes to freckles + tan
Blood = contributes to pink (or blue) colourisation
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What is the role and layers within the dermis?
Supports the dermis via collagen + elastin fibres
- papillary layer - areolar tissue (loose connective tissue)
- reticular layer - has a fibrous network
- blood vessels form the papillary and cutaneous plexus
- sensory receptors
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What are the functions of hair?
Protection
Insulation
Sensations - animal whiskers
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What is the structure of hair?
Inner medulla - softer keratin
Outer cortex - stiffer keratin
Hair shaft on outside covered by cuticle - hard cuticle
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What is the structure of hair follicle?
Internal root sheath - surrounds hair root + deeper portion of the shaft
External root sheath
Glassy membrane - thickened clear layer wrapped around in the dense connective tissue sheath
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How does hair grow?
- the hair papilla contains blood vessels + nerves needed for growth
- the hair matrix is the site of basal cell division whereby daughter cells are pushed towards the surface
At the end of the growth cycle, the follicle becomes inactive + connections between hair follicle + root break down so old hair is shed
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What is the function of nails + where does nail growth occur?
To protect + limit distortion
The nail root is where cell division for growth occurs
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What are the 2 kinds of sweat glands?
Apocrine sweat gland:
- found in pubic region + axillae
- secrete a thick, odorous fluid
Merocrine sweat gland:
- discharge a watery fluid onto skin surface
- used for surface skin cooling, excretion + protection
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What do the following types of burns effect?
- first degree
- second degree
- third degree
1. Affect the epidermis + cause reddening
2. Burns involve dermis damage + blisters and some scar tissue forms
3. Burns extend to hypodermis whereby sensory nerves are destroyed
- may disrupt fluid + electrolyte balance, thermoregulation + protection from infection
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What are the 4 steps in repair of injury?
Step 1: Bleeding may occur + mast cells trigger an inflammatory response
Step 2: After several hours…
- Clot (scab) with fibrin network forms
- Cells of stratum basale migrate
- phagocytic cells arrive + remove debris
- Epithelial cells migrate
Step 3: One week after the injury...
- Mesh produced by fibroblasts underlying wound
- Scab undermined by epidermal cells
- Phagocytic activity almost ended
- Fibrin clot breaking up
Step 4: After several weeks...
- Epidermis is complete
- Shallow depression at injury site initially
- Fibroblasts activity continues
- Scar tissue – contains more collagen than accessory structures
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What are the intrinsic and extrinsic factors for skin ageing?
Intrinsic:
- cell activity
- growth factors / hormones
- immune sensitivity
Extrinsic:
- sunshine exposure
- smoking
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What are the intrinsic + extrinsic results of skin ageing?
Intrinsic:
- dermal thinning + wrinkling
- white hair
- increased infection risk + slower healing
Extrinsic:
- increased wrinkling
- increased skin cancer risk
