Bio Class 8 Flashcards
Endocrine vs Exocrine glands
Endocrine
- product: hormones
- location: blood stream
- ducts: no ducts, straight into capillary network
Exocrine
- product: everything but hormones, mucus, sweat, stomach acid, etc
- location: body surface/cavity
- ducts: yes except for mucus cells
Steroids vs Peptides
- Made from?
- Location of receptor?
- Mechanism of action?
- Speed of effects?
- Longevity of effects?
Steroid
- made from cholestrol
- receptor inside cell
- binds to DNA and modifies transcription
- slow effect but more permanent
- eg. testosterone, progesterone, estrogen
Peptide
- made from amino acids
- receptor on surface
- acts as a secondary messenger
- fast effect but temporary
What is the fastest hormone?
epinephrine
Hormone release
Neuronal
- neurons trigger the release of hormones (eg. adrenaline)
Hormonal
- hormones trigger release of hormones (eg. Tropic hormones:ACTH)
Humoral
- particles in blood trigger release of hormones (eg. high glucose releases insulin)
Anterior vs posterior pituitary (characteristics)
Anterior
- produces 6 hormones: Tropic - FSH, LH, ACTH, TSH, direct hormone- Prolactin, GH
- Has glandular tissue
- also known as “adenohypophysis”
- hormones are made and released
Posterior
- produces 2 hormones: vasopressin (adh), oxytocin
- known as “neurohypophysis”
- has nervous tissue
- hormones are stored & released
Anterior pituitary process
Hormone-making cells that produce hormone and travels via capillary networks that are connected by portal vein
- every hormone released from anterior pituitary has a release hormone from hypothalamus
Posterior pituitary process
Neuron makes hormones and axon will start in hypothalamus and release in posterior pituitary
Arteries vs Veins
- pressure, how it moves, muscular walls, elasticity
Arteries
- high pressure because blood is pushed out
- blood moves by forward momentum
- has muscular walls so can direct blood wherever needed in body
- is elastic so can regain shape after stretching out
Veins
- low pressure
- blood moves by anything that squishes veins (eg. skeletal muscle contracting)
- no muscular walls or elasticity
- has valves to prevent back flow when muscles relax
Capillaries
Exchange of nutrients and waste, very thin
What is blood called when it’s in the…
lymphatic system?
in tissues without cells?
inside veins & arteries
lymph
interstitial fluid
plasm
Lymphatic system
When blood exits arteries, osmosis will bring it back in through the vein but there’s a lot of blood that exits so it goes through lymph system
- the lymph node is a concentrated area of WBC which monitors infections
Flow of blood
- From body you get deoxygenated blood that enters the right atrium through the superior/inferior vena cava
- The blood goes from RA to RV through the tricuspid atrioventricular valve
- Blood goes from RV to lungs through pulmonary artery by passing the pulmonary semilunar valve
- Blood reaches lungs & gets oxygenated
- Blood enters LA through pulmonary veins
- Oxygenated blood goes from LA to LV by passing the bicuspid (mitral) AV valve
- From LV to go to rest of body it passes the aortic semilunar valve through the aorta
Why is the LV more thick?
Blood needs higher pressure because being pumped to rest of the body which is further apart than pumping to eg. lungs
Lub Dup sound
Lub - where systole begins; AV valves close
Dup - where distole begins; Semilunar valves close
- Contraction of atria will push blood down and almost immediately the ventricle will start contracting.
- To ensure no back flow of blood, AV valves close
- Then pushed through the semilunar valves and when it relaxes it will close too
Systole vs Diastole
Systole- artery is contracted
Diastole - artery is relaxed
BP
Systole/Diastole
Pressure of artery when contracted / pressure of artery when relaxed
BP is directly proportional to…
Cardiac output
Peripheral resistance
Cardiac output
Stroke volume x HR
vol/beat) x (beat/min
How to change stroke volume
- Change the blood volume
- Change activity level
- Change posture
Frank-Starling law
More blood in –> heart stretching –> heart contracting –> more blood out
Peripheral resistance
How hard it is to get the blood through vessels
Vessels dilate = flow will increase = PR will decrease = bp will decrease
Vessels constrict = flow will decrease = PR will increase = bp will increase
Tetany
As ap builds up, you achieve tetany
Why do you not want tetany in cardiac muscle cells but in skeletal muscle cells?
You want to be able to hold yourself with extended skeletal contractions at extended periods of time
Autorhythmic cells
known as pace makers
- found in the SA node and then will generate AP
- will transmit stimulus to LA and RA forcing it to push into ventricles via contractions
- will pass through AV, which will delay it a bit to allow atria to contract first
- will go through bundle branches in RV then purkinje fibers in LV where it will then be pumped bottom up in ventricle to cardiac muscle cells
Reasons why conduction system is important
- Atria and ventricle cannot communicate electrically, only through gap junction so need conduction system
- AV node delays impulse allowing atria to contract first
- Impulse travels to bottom of heart before entering ventricular muscle, allowing ventricle to contract from bottom to top
Blood composition
Plasma (54%) - water, glucose, lipoproteins, plasma proteins, hormones, wastes Leukocyte (1%) - WBC and platelettes Hematocrit (45%) - RBC
Blood Gas Transport
- oxygen is non-polar so only 3% dissolves in blood plasm
- the 97% transports via hemoglobin
- Hb goes to lungs, fills up with oxygen then goes to tissue & unloads 30% of oxygen
Hemoglobin
Has 4 polypeptides which have co-operative binding
- Hb has a higher affinity for oxygen in lungs vs releases oxygen it decreases affinity
Co-operative binding
When 1 polypeptide binds to hemoglobin, the affinity of other polypeptides to bind oxygen
Co2 transport
- Carbon dioxide is non-polar so it won’t completely dissolve
- 7% dissolves in plasma, 20% on Hb
- 73% converted to bicarb and dissolved in plasma
CO2 + H2O H2CO3 H+ + HCO3-
Non-specific defense
- Barriers: mucus, skin, hair, ear wax
- Chemicals: lysozyme in saliva and tears, stomach acid, complement system
- Cells: neutrophils (phagocytes), natural killer
Complement system
Proteins that insert into membranes and act as water channels to allow water in cell and then lyse it
B-cell immunity (humoral immunity)
Make antibody and dumps it in blood
- has DNA rearrangement to allow to make variety of antibodies
- b-cell is found on surface of cell
- 2 types: plasma b-cells (specific and dump into blood) AND memory b-cells (remember for next infection)
Antigen
foreign protein that trigger immune response
Antibody
specific marker for antigen
- able to carry 2 antigens with the SAME epitope
Pathogen
disease causing organism
T-cells: Cell mediated immunity
- Killer T cells
- respond to MHC I
- kills foreign bodies - Helper T cells
- responds to MHC II
- secrete chemicals to increase B- & T- cell proliferation
MHC I vs MHC II
MHC I
- present in almost all cells
- presented on surface of cell
- if it meets a foreign antigen, it will kill it
MHC II
- found on B- cells & macrophages
- allows cells to display eaten particles on cell surface
Primary and Secondary immune response
Primary exposure to antigen - (7-10 days: primary immune response)-> Ab, Active t cells, memory cells - (<1 day: secondary immune response)-> Ab, Active t cells, more memory cells
More exposure to antigens = stronger response
How does a vaccination work?
Introduce antigens to allow immune response to make ab so that if you get exposed later, it’ll be considered a secondary immune response
Autoimmunity
- immune system targets foreign proteins in body
- produces b and t cells that recognize different proteins including your own
- self-reactive lymphocytes will attack own ag & cause autoimmune response
- to prevent this, you need to kill these self-reactive lymphocytes
Many random B & T cells are produced that recognize both self + non-self proteins –> exposed to all normal “self antigens” –> B + T cells that recognize self have to either be inactive (anergic) or apoptosis –> B+ T cells that recognize non-self will be released into circulation
Where are T cells and B cells produced?
bone marrow
Where are T cells and B cells matured?
T cells: thymuc gland
B cells: bone marrow
