Lecture 18 - Lymphatic, Immune and Respiratory Systems Flashcards
role of lymphatic system
- return excess tissue fluid back to the blood vascular system
what is the structure of the lymphatic system?
- lymph duct
- lymph trunk
- lymph node
- lymphatic collecting vessels with valves
- lymphatic capillaries
primary lymph organs
- thymus
- red bone marrow
secondary lymph organs
- lymph nodes
- tonsils
- spleen
- aggregated lymphoid nodules
- appendix
what is lymph?
- clear water containing many different substances
what are lymphocytes?
- a type of white blood cell that is part of the immune system
- 2 main types of lymphocytes: B cells and T cells
how does lymph occur in the body?
is the collection of the extra fluid that drains from cells and tissues in your body and isn’t reabsorbed into your capillaries
lymph vessels
- tubes that collect and carry lymph through the body to lymph nodes and back to veins
- one-way circuit only towards the heart
lymphatic capillaries
- the smallest vessels
- first to receive lymph in the circuit which drain into collecting vessels
- have overlapping cells which forms flap-like minivalves
lymph nodes
- 500 small lumps of tissue on collecting lymphatic vessels which contain white blood cells
- they filter and cleanse the lymph fluid of foreign substances
where are lymph nodes found?
- deep cervical
- axillary
- inguinal
- tracheobronchial
- aortic
- iliac node
lymphoid tissue
a tissue in which lymphocytes are found and gather to fight invading microorganisms
lymphoid follicles
- densely packed lymphocytes
- occurs when lymphocytes divide and generates many copies
what are aggregated lymphoid nodules?
- an important part of the gut-associated lymphoid tissue (GALT)
- circular or oval patches in the small intestine
- aka peyers patches
what is the circulation of the lymphatic system?
Lymph capillaries → collecting lymph vessels → Lymph nodes
→ larger lymph vessels converge into lymph trunks → lymph ducts → venous system at the junction of the subclavian and internal jugular veins via
1. The right lymphatic duct and
2. The thoracic duct
what are lacteals?
- are lyphatic capillaries in the small intestine
- absorb digested fats and lymph in the area
what is chyle?
- the milky bodily fluid formed in the lacteal system of the intestine
- primarily composed of fat
what are the functions of the major respiratory organs?
- exchange gases
- regulate pH
spleen
- largest lymphoid organ
- has blood cleansing functions
appendix
- small finger-shaped tube that branches off the first part of the large intestine
- secondary lymphoid organ
appendicitis
inflammation of the appendix
what are bubos?
- swollen/inflamed lymph nodes
what is pitted edema?
- occurs when excess fluid builds up in the body, causing swelling
- when pressure is applied to the swollen area, a “pit”, or indentation, will remain
what is the bubonic plague?
- is an infection of the lymphatic system
- caused by the bite of an infected flea
what is filariasis?
- aka elephantiasis
- disease caused by a chronic mosquito-borne parasitic infection and causes the lymphatic system to be blocked and swell up
how do lymphocytes develop?
1.) origin = t and b lymphocyte precursors originate in red bone marrow
2.) maturation = b-cells mature in the bone marrow, t-cells migrate to blood in the thymus
3.) seeding = leave thymus and bone marrow and seed the secondary organs and recirculate through blood and lymph
4.) lymphocyte is activate when an antigen receptor binds its antigen
5.) proliferation = in lymphoid tissue, activate lymphocytes multiply and differentiate into effector and memory cells. they circulate in the blood, lymph and secondary organs
b-cells (bone marrow)
- they differentiate into plasma cells that secrete antibodies and mark/flag foreign cells for destruction by macrophages
t-cells (thymus)
- attacks foreign cells directly by binding to it and secrete proteins that cause apoptosis (programmed cell cell)
effector cells
relatively short-lived activated cells that defend the body in an immune response
memory cells
cells that remember particular antigens so if they appear in your body in the future, your immune system can mount a defence quickly
what is mucosa-associated lymphoid tissue (MALT)?
- scattered along mucosal linings of the body
- initiates immune responses to specific antigens encountered
lymphangitis
inflammation of a lymphatic vessel
pulmonary respiration
the process of air flowing into the lungs during inspiration (inhalation) and out of the lungs during expiration (exhalation)
cellular respiration
takes place in the cytoplasm and mitochondria of each cell of the body
eupnea
normal, good, healthy and unlabored breathing
apnea
when you stop breathing while asleep or have almost no airflow
dyspnea
shortness of breath
COPD
- chronic obstructive pulmonary disease
- refers to a group of diseases that cause airflow blockage and breathing-related problems
surfactant
an essential lipid-protein complex to maintain an working respiratory surface in the lungs
what is a pneumothorax?
- collection of air outside the lung but within the pleural cavity
- occurs when air accumulates between the parietal and visceral pleurae inside the chest
- the air accumulation can apply pressure on the lung and make it collapse.
atelectasis
the collapse of a lung or a lobe
alveoli
very small air sacs where the exchange of oxygen and carbon dioxide takes place
bronchioles
smallest airways that branch off bronchi which to the alveoli
components of upper respiratory tract
- nasopharynx
- oropharynx
- laryngopharynx
- larynx
what is important about paranasal sinuses?
- lined with respiratory mucosa which helps to moisten and warm the inhaled air
- drains into the nasal cavity
where is the larynx located?
spans the distance of C3 to C6 vertebrae on the anterior neck
how does thoracic volume change during inspiration?
- thoracic cavity and pleural cavity increase in volume
- lungs stretch = lung volume increases
- air flows into lungs
how does thoracic volume change during expiration?
- thoracic cavity and pleural volume decrease in volume
- lungs recoil = lung volume decreases
- air flows out of lungs
how many lobes are in the lungs?
- 3 lobes on right lung
- 2 lobes on left lung
