Anatomy π« Flashcards
What are bones?
Calcified connective tissue.
How many bones are found in the body?
206
What are the functions of bones?
1) Support body & shapes it (framework for the body)
2) Protection of certain organs e.g. skull protects brain.
3) gives attachment to muscles & joints
4) Long bones provide levers for muscles to move joints
5) Formation of blood cells in red marrow.
6) Store & provide body with minerals; Calcium & phosphorus in emergencies.
What are bones classified according to?
According to:
A. Position.
B. Development.
C. Structure.
D. Shape.
Classification of bones according to position
Axial and appendicular
What is the axial skeleton?
skull, vertebral column & thoracic cage.
What is the appendicular skeleton?
Bones of upper and lower limbs
Describe the vertebral column
has 32-33 vertebrae, divided into:
1) Cervical (neck): 7 cervical vertebrae.
2) Thoracic (chest): 12 thoracic vertebrae.
3) Lumbar (low back): 5 lumbar vertebrae.
4) Sacrum: 5 fused sacral vertebrae.
5) Coccyx (tail): 3-4 fused coccygeal vertebra
What is the function of the thoracic cage?
It protects heart & lungs & allows breathing
What does the thoracic cage consist of?
1) Sternum: anteriorly.
2) Ribs: 12 pairs laterally.
3) 12 Thoracic vertebrae: posteriorly.
Compare between the upper limb and lower limb
What are bones classified into according to ossification?
Intramembranous and intra-cartilaginous bones
What is the mechanism of formation of intramembranous bones?
The condensed mesenchymal tissue β undergoes bone formation directly
What are examples of intramembranous bones?
ο shaft of clavicle
ο skull cap
ο Bones of face.
What is the mechanism of formation of intra-cartilaginous bones?
- The condensed mesenchymal tissue β chondrification first to form a cartilaginous model
- Then bone is deposited in this model
What are examples of intra-cartilaginous bones?
All bones of limbs except shaft of clavicle.
Compare between cancellous (spongy) bones and compact bones
What are bones classified into according to structure?
Cancellous (spongy) and compact
What are bones classified into according to shape and give examples for each one?
What are the parts of a long bone?
A long bone consists of 2 ends & a shaft.
What is (epiphysis)?
The end of long bone.
What is the epiphyseal Cartilage?
- a hyaline cartilaginous plate
- It is the site of growth in length of bone.
What is the diaphysis and what is it composed of?
- The shaft of long bone
- Composed of:
ο² a cylinder of compact bone with a cavity
ο² Medullary cavity contains bone marrow.
ο² Bone marrow occupies the marrow cavity in long & short bones & cancellous bone in flat & irregular bones:
β’ At birth, marrow is red & hematopoietic.
β’ At 7 years of age, yellow marrow begins to appear in distal bones of limbs.
What is the metaphysis?
Wide expanded end of shaft close to epiphyseal cartilage.
What is the periosteum and what is its function?
- A fibrous membrane covering Shaft.
- responsible for growth of bone in thickness
What is the blood supply of long bones?
Nutrient artery: Passes through nutrient canal
Periosteal arteries
Metaphyseal arteries
Epiphyseal arteries
NB. The epiphyseal plate is avascular (= doesn`t have blood supply) & is supplied by diffusion.
What are the blood supply of short bones?
Via periosteal vessels.
β A 67-year-old woman presented to the emergency department with 4-month history of worsening lower back pain.
β There was no history of trauma or falls.
β She completed her investigations with serology and radiology.
β Based on the mentioned history and investigations, the patient was diagnosed with severe osteoporosis.
What are the main cells responsible for bone formation and resorption?
- osteoblast cell is responsible for bone formation
- while osteoclast is responsible for bone resorption
What are the two main hormones responsible for calcium deposition and removal from bones?
- calcitonin is responsible for calcium deposition in bone
- while parathormone is responsible for mobilization of calcium from bone
What are contractile fibers responsible for?
Contractile fibers responsible for movement, controlled by nervous stimuli.
What are the sites of skeletal muscles?
- Attached to bone.
- Around joints.
- 40-50% of body mass.
What are the sites of smooth muscles?
- Wall of internal viscera (longitudinally & circularly) to produce peristalsis.
- In blood vessels to control the lumen caliber.
- In storage organs to produce expulsion of contents.
What are the sites of cardiac muscles?
In myocardium.
Compare between skeletal, smooth and cardiac fibers according to contraction and striation
What are the nerve supply and control of skeletal muscle fibers?
Somatic mixed nerve (motor & sensory).
What is the nerve supply and control of smooth muscle fibers?
- Autonomic nerves
- Also, controlled hormonally
- And by local stretch action.
What is the nerve supply and control of cardiac muscle fibers?
- Autonomic nerves
- conducting system: spontaneous rhythmic contraction
What is the shape of the muscle cell in skeletal muscle fibers?
Multi nucleated
What is the shape of muscle cell in smooth muscle fibers?
Spindle-shaped with single nucleus.
What is the shape of muscle cells in cardiac muscle fibers?
Spiral, Branch & unite together (one syncytium).
What are the attachments of a skeletal muscle?
2 attachments:
1) Origin: is the more fixed attachment.
2) Insertion: is the more mobile attachment.
What are the functions of skeletal muscles?
1) Produce movement.
2) Maintain posture.
3) Stabilize joints.
4) Generate heat.
What are skeletal muscles classified into according to fascile arrangement?
1- Fusiform
2- Parallel
3- Convergent
4- Unipennate
5- Bipennate
6- Multipennate
7- Circular
What are skeletal muscles classified according to the action of muscles?
1- Prime movers
2- Antagonists
3- Synergists
4- Fixators (stabilizers)
What is the function of prime movers? and give an example.
- Responsible for initiation of movement.
Example: brachialis in elbow flexion.
What is the function of antagonists? and give an example.
- oppose action of prime movers.
Example: triceps antagonizes elbow flexion produced by
brachialis.
What are the functions of synergists? and give an example.
- Act with each other to perform with more efficient contraction.
Example: Biceps helps brachialis muscle.
What are the functions of fixators? and give an example.
- Stabilize the joint on which the prime mover acts.
Example: rotator cuff muscles stabilize the humerus which is the origin of brachialis
What are skeletal muscles classified into according to the number of joints the act upon?
Uni-articular: Brachialis
Bi-articular: Sartorius
Multi-articular: Flexors and extensors of the digits
What is Lou Gehrigβs disease?
Is a fatal neurologic disease that attacks the neurons responsible for controlling voluntary muscles.
What are the earliest symptoms of Lou Gehrigβs disease?
The earliest symptoms may include cramping, twitching, and muscle weakness,
What happens to muscles with Lou Gehrigβs disease with time?
The muscles gradually atrophy, and patients lose the ability to swallow, speak and finally to breath.
What is fascia and what are its types?
-Connective tissue lying between skin & underlying muscles & bones.
-Superficial fascia, Deep fascia
What are the characters of superficial fascia?
1) Mixture of loose areolar & fatty tissue that lies between skin & deep fascia.
2) Dense in the scalp, the palm of the hand, sole of foot & back of the neck.
3) Thinnest with no fat: over penis, scrotum, eyelid, auricle of the ear
4) May contain (fat, cutaneous vessels, nerves, lymphatics, and glands)
What is the function of superficial fascia?
1) Bad conductor to heat so keeping body temperature constant.
2) Fills up hollows & rounds off irregularities so gives rounded appearance & smooth
outline particularly in females.
3) Facilitates skin movement over underlying structures.
4) Acts as a medium for cutaneous vessels, nerves & lymphatics.
What are the definition of deep fascia?
-Membranous layer of connective tissue that is denser & lies deep to superficial fascia.
-It is present in the neck, upper & lower limbs.
What are the types of deep fascia?
-Investing fascia: covers surface of the muscle.
-Inter-muscular septa: lie between muscles.
-Retinacula: localized transverse thickenings of deep fascia around wrist and ankle joints to hold long tendons in place.
-aponeurosis: thicker parts of deep fascia in the palm of hand and sole of foot and scalp
-sheaths for neuromuscular bundles: As femoral and carotid sheathes.
-tendons: Fibrous bands that connect muscles to bones or cartilage or connecting abdominal viscera.
-Ligaments: Fibrous bands like tendons that connect bones to bones or cartilage or are folds of the peritoneum serving to support visceral structures.
-Raphe: The line of union of symmetrical muscles through interdigitation of their tendentious ends.
What does CVS consist of?
Consists of: heart, blood vessels & blood.
What does CVS transport? and what does blood transport?
ο It transports blood to and from the tissues.
ο Blood transports O2 & nutrition to tissues for metabolism & transports CO2 & wastes from tissues to lung & kidney for elimination
What is the site of the heart?
-in the middle of the thorax above the diaphragm.
-extending slightly to the left.
What is the size of the heart?
about the size of an individualβs closed fist.
What are the general features of the heart?
-It is surrounded by a thin membrane called pericardium
- It is divided into 4 chambers
-Interatrial septum separates 2 atria
- An interventricular septum separates 2 ventricles
There are 2 types of valves: Atrioventricular and semilunar
What are the chambers of the heart? and what are the structures associated with atria?
It is divided into 4 chambers:-
1) The upper 2 champers are right & left atria, each atrium has an ear-like projection called the auricle
2) The lower 2 champers are right & left ventricles
What are the types of Valves?
There are 2 types of valves:
1) Valves ( ) atria & ventricles βcuspid valvesβ or βatrioventricular valvesβ
2) Valves at the base of large vessels leaving the ventricles βSemilunar valvesβ
where and when does blood flow through vessels?
blood passes from the heart in arteries, through tissues in capillaries & back to the heart in veins
What are the types of circulations?
Systemic, pulmonary, and portal
Systemic circulation
ο Oxygenated blood is pumped from the left ventricle to the aorta where it is distributed to various parts of the body through arteries, arterioles, and finally the capillaries in the tissues.
ο Deoxygenated blood from the capillaries passes into small veins then large veins and finally returns to the right atrium via the superior and the inferior vena cava
Pulmonary circulation
ο Deoxygenated blood passes from the right atrium into the right ventricle.
ο Then pumped to the pulmonary trunk then to lungs through two pulmonary arteries, arterioles and finally capillaries around the alveoli; where carbon dioxide is eliminated and the blood is oxygenated.
ο Oxygenated blood from the capillaries passes into venules, veins, then to the left atrium via four pulmonary veins.
ο Then passes from the left atrium into the left ventricle.
Portal circulation
Circulation of the blood between two sets of capillaries.
-One in the digestive tract: Venous blood from the stomach, intestines, pancreas, and spleen does not return directly to the heart, but it drains into the liver via the portal vein.
-One in the liver: In the liver, the portal vein breaks up finally into the 2nd set of capillaries (liver sinusoids), which drain into the heart via the hepatic veins and inferior vena cava
What are blood vessels?
The channels through which the blood is moved.
What are the types of blood vessels?
arteries, veins, and capillaries.
What are arteries?
Vessels or tubes carry blood away from the heart & distribute it to various tissues by their branches
What are the types of arteries?
-arterial anastomosis
-end arteries
-wavy(tortuous arteries)
What is the definition of arterial anastomoses?
The terminal branches of arteries communicate with those of adjacent arteries.
What are the sites of arterial anastomosis?
ο Around joints of limbs.
ο In hand & foot.
ο At the base of the brain.
ο In abdomen ( ) stomach & intestine
What is the importance of arterial anastomosis?
Provides a collateral circulation if an artery becomes occluded to maintain blood flow to the area
What is the definition of end arteries?
arteries whose terminal branches do not anastomose adjacent arteries
What are the sites of end arteries?
ο Retinal
ο Renal, splenic.
ο Cerebral, coronary, and pulmonary arteries.
What is the importance of end arteries?
Their occlusion disrupts blood supply to their organs; resulting in ischemia and infarction
What is the definition of wavy arteries?
arteries which have wavy course mostly as they supply expansile or moving organs
What are the examples of wavy arteries?
ο facial artery
ο Lingual artery
ο Uterine artery
ο Splenic artery
What are veins?
Vessels or tubes carrying blood towards the heart & they have tributaries
Wat are the types of veins?
Pulmonary and systemic
Pulmonary veins
Return oxygenated blood from lung to left atrium
Systemic veins
-Return deoxygenated blood from body to right atrium In limbs & neck, veins have valves to ensure unidirectional flow of blood.
-Divided into 3 sets:
1) Superficial veins: in the superficial fascia
2) Deep veins: accompany arteries
3) Dural sinuses: inside skull ( ) 2 dural layers
Compare between arteries and veins?
-DIRECTION of carrying of the blood (away-to)
-TYPE of carried blood (oxy-de) βexcept pulmonaryβ
-WALLS (rich in SM and EF - poor) (thick wall and narrow lumen - reverse)
-presence of VALVES (no-yes)
-BRANCHES or TRIBUTARIES (branch - tributaries)
What are the types of connections between arteries and veins?
1-capillaries
2-AV Shunts
3-blood sinusoids
capillaries
-Simple vascular endothelial networks between arterioles & venules in tissues
-Their walls are very thin to allow the exchange of oxygen, nutrients & wastes between blood & tissue.
-Cartilage, cornea & epidermis of skin are devoid of (without) capillaries
What is the definition of AV Shunts?
Direct communications ( ) arterioles & venules proximal to capillaries so, blood passes directly from arterial to the venous side without passing in capillaries
What are the sites of AV shunts?
ο The dermis of the skin (to regulate body temperature)
ο The auricle of ear, Tip of the Tongue, Nose, Lips Intestine (to regulate the rate of absorption)
ο The erectile tissue of sex organs (to regulate erection)
What are blood sinusoids?
Wide tubular spaces lined incompletely with phagocytic cells
What are the sites of blood sinusoids?
liver, spleen & bone marrow
What is the definition of the lymphatic system?
considered a part of both the circulatory & immune systems.
What are the components of the lymphatic system?
-lymph
-lymphatic vessels
-lymphoid tissue
What is the function of the lymphatic system?
ο drainage of extracellular tissue fluid to the blood stream, this fluid is called lymph (clear water)
ο removal of cellular debris & microorganisms
What are the components of the lymphatic system?
-lymph capillaries
-lymph vessels
-lymph ducts
-lymph nodes
-lymphoid tissues
Lymph cappilaries
ο network of fine blind end capillaries
ο drain lymph from extracellular spaces of tissues
What are lacteals?
lacteals are a special type of lymph capillaries that receive absorbed fat from the small intestine.
Lymph vessels
ο lymph capillaries join to form thin-walled lymph vessels
ο have numerous valves allowing lymph to pass in one direction
ο lymph within vessels passes in stations of lymph nodes
ο lymphatics carry lymph to lymph node are called afferent lymphatics
ο lymphatics that carry lymph away from L N are called efferent lymphatics
ο areas with no lymphatics: teeth, bone marrow, cornea & CNS
Lymph ducts
lymphatic vessels unite to form lymph duct
-right lymph duct:
ο drains lymph from the right side of head, neck, thorax & right upper limb
ο it end in junction ( ) right subclavian & right internal jugular v.
-thoracic duct:
ο drains rest of body
ο begins in the abdomen as cisterna chyli & ascends through the thorax
ο it ends in junction ( ) left subclavian & left internal jugular v.
What is the definition of lymph nodes?
small oval bodies of lymphatic tissue along lymph vessels through which lymph is filtered on its way to the venous system
What are the important groups of lymph nodes?
ο axillary: for upper limb & breast
ο cervical: for head & neck
ο mediastinal: for thorax
ο iliac: for the pelvis
ο aortic: for abdomen
What is the function of lymph nodes?
ο filtering station as they prevent microorganisms & foreign bodies in lymph from entering the blood.
ο formation of lymphocytes
ο formation of antibodies
What are lymphoid tissues?
β collection of lymphoid tissue other than lymph nodes eg: palatine tonsils, adenoid, thymus & spleen
What is the function of lymphoid tissues?
defense mechanism for the body.
What is the definition of jointsΨ
Articulation between two or more bones.
What are Joints classified according to?
- According to the nature of tissue between the articulating bones
- According to mobility
What are bones classified into according to the nature of tissue between the articulating bones?
ο² Fibrous.
ο² Cartilaginous.
ο² Synovial.
What are joints classified into according to mobility?
ο² no mobility.
ο² Limited mobility.
ο² Freely mobile.
What are the characteristics of fibrous joints (Synarthroses)?
ο Articulating bones are separated by fibrous tissue.
ο Produce no mobility.
Compare between the types of fibrous joints
What are the characteristics of cartilaginous joints (Amphiarthroses)?
ο Bones are united by cartilage.
ο Limited mobility.
Compare between the types of cartilaginous joints
What are the characteristics of synovial joints?
ο Freely mobile joints.
ο Characterized by presence of joint cavity.
ο Articular surfaces are covered by hyaline cartilage.
ο Bones are surrounded by fibrous capsule.
ο Presence of synovial membrane and synovial fluid
What the what is the synovial membrane line and what is its function?
ο² Lines the inner surface of capsule and covers non articular parts of bones.
ο² Its function is to produce and absorbe the synovial fluid.
What are the functions of the synovial fluid?
1) Allow free mobility of joints.
2) Lubrication of articular cartilage.
3) Provides nutrition of articular cartilage and structures inside joint cavity.
What are the structures inside joints?
What are the types of synovial joints according to the number of axes?
1) No axis joints.
2) Uni-axial joints
3) Bi-axial joints.
4) Poly axial joints.
What are the types of synovial joints according to the shape of articulating bones?
1) Plane joints.
2) Hinge joints.
3) Pivot joints
4) Saddle joints
5) Ellipsoid joints.
6) Ball & socket joint.
What are uni-axial joints?
- Hinge joints (Ginglymus)
- Pivot joints (Trachoid)