Normal Body Systems Flashcards
What is blood composed of?
Plasma, Erythrocytes, Leukocytes and Platlets
What are the 5 types of leukocytes?
~ Neutrophils
~ Eosinophil
~ Basophil
~ Lymphocyte
~ Monocyte
What is it called when multiple uninucleated cells merge to form multinucleated cells?
Syncytium
Name the 3 types of muscle tissue.
Cardiac, smooth and skeletal
What are the functions of erythrocytes?
~ Transport respiratory gases
What are the ganulocytes and agranulocytes?
Granulocyute ~ Neutrophils; Basophils; Eosinophils
Agranulocytes ~ Monocytes; Lymphocytes
What are haematopoietic tissue and what are the types?
Tissue that actively or potentially produce blood cells
Myeloid ~ bone marrow; all other blood cells
Lymphoid - lymphatic system; lymphocytes and NKC
Give a key feature of each Leukocyte.
Neutrophils ~ 2-5 lobes; granulated
Basophils ~ 2-3 lobes; dark granules
Eosinophils ~ bilobed
Monocyte ~ large nucleus kidney shaped
Lymphocyte ~ thin rim of cytoplasm
What is the function of muscle?
~ maintain and change posture
~ locomotion
~ movement of internal organs
What type of protein is: i) myosin ii) actin ?
i) Thick fibrillar
ii) Thin globular
Describe the sliding filament theory on a molecular level.
1) ATP binds to myosin head and is converted into ADP + Pi cocking the head.
2) Myosin is attatched to ADP and Pi, Ca2+ binds to troponin which displaces tropomyosin and exposes myosin binding sites.
3) Myosin binds to actin filament and ADP and Pi dissociate from myosin head causing powerstroke.
4) ATP binds to myosin head resulting in detatchment of myosin from actin. ATP converted into ADP + Pi and myosin in recocked ready to perform another power stroke.
What are the layers of the skin?
Epidermis - upper layer, physical barrier from environment
Dermis - second layer, contains mechanoreceptors, thermoreceptors, lymphatic vessels, blood vessels and different glands
Hypodermis - subcutaneous tissue, larger blood vessels and nerves; main function is fat storage
Name and describe epithelial cell classification.
Simple - one cell thick
Stratified - many cells thick
Pseudostratified - appears many cells thick but all cells attatched to basal membrane
Squamous - squashed cells
Cuboidal - Cube shape
Columnar - column-like
What is meant by primary and secondary lymphoid tissue?
Primary - lympoid cells are produced, no immune activity
Secondary - where mature lymphocytes are activated
Give two examples of both primary and secondary lymphoid tissue.
Primary - Bone marrow; Thymus
Secondary - Lymph nodes; Lymphatic vessels
Describe the two types of immune responses.
Innate - rapid response; limited specificity; constant response
Adaptive - slow response; high specificity; improve during response
NOTE:
if innate repsonse stops infection adaptive response doesnt need to be activated
What are the 3 features of the immediate immune response?
Barriers - physical and chemical
Antimicrobial peptides - kill pathogens
Complement system - plasma proteins that react in a cascade to opsinize pathogens and induce an inflammatory response
What roles do cytokines play in an inflammatory response?
- Recruits/attracts more leukocytes
- Vasodilation of blood vessels
- Increased blood vessels permeabilty
What are the 3 roles of anitbodies?
Neutralisation - prevent pathogen binding to
Opsonization - allow macrophage to bind to pathogen
Complement activation - promotes opsonisation
Describe the complement system.
A group of 30 proteins that promote opsinisation via a cascade of enzymatic reactions
How does the induced innate immune response work with bacteria?
- TLR4 binds to bacterial LPS promoting gene expression of pro-inflammatory cytokines via a signal transduction pathway
- Phagocytosis
How does the induced innate immune response work with viruses?
- TLR7 detects ssRNA activating a transduction pathway promoting expression of genes coding for
IFN-alpha and IFN-beta. - Type 1 Interferons activate NK cells and proliferate NK cells which kills virus infected cells by apoptosis
What are the 4 parts of the stomach?
- cardia
- fundus
- body
- pylorus
What are the endocrine substances secreted by the pancreas, and their respective cells?
β cells - secrete insulin
⍺ cells -secrete glucagon
δ cells - secrete somatostatin which inhibits other endocrine secretion
What are the functions of the kidney?
- homeostatic regulation of water and ions
- excretion of metabolic waste
- filtration
- production of hormones
What are the 4 processes of the nephron?
- filtration
- reabsorbtion
- secretion
- excretion
What cells produce testosterone?
- Leydig cells
Give an example of a weak androgen and where it is produced.
- DHEA
produced in the adrenal cortex and is present in both male and female
NOTE:
steroid hormones are derived from cholestersol
Actions of testosterone?
- increased body hair growth
- enlargement and thickening of larynx
- thickening of skin
- muscle growth
- thickening and strengthing of bones
Actions of estrogens?
- development and regulation of other hormones and sex characteristics
- maturation of germ cells
- anabolic effects on bones and cartilage
- thickening of uterus lining
Describe the structure of a sarcomere.
- A band is length of thick myosin filament
- I band is region of just thin actin
- M line is middle of sarcomere
- H zone is region of just myosin
- Z disc end of each sarcomere
What are the 2 types of smooth muscle?
Vascular - arteries, veins, lymphatic vessels
Visceral - GI tract, airways etc
Smooth muscles are spindle-shaped
What is the mechanism of smooth muscle contraction?
1) L-type Ca2+ voltage-gated channels open, influx of calcium ions
2) Ca2+ stimulates release of Ca2+ from sarcoplamic reticulum via Ryanodine receptors (RYR)
3) Ca2+ forms complex w/ calmodulin which activates Myosin Light Chain Kinase (MLCK)
4) MLCK phosphorylates myosin head which stimulates muscular contraction
What is epithelial tissue and what is its function?
- tissue covering external surfaces of the body and lining hollow structure inside the body (EXCEPT blood and lymphatic vessels)
- absorption
- defence/protection
- secretion
- sensation
- exchange/communication
