The respiratory/excretory system Flashcards
Which areas affect the air that we breathe in the respiratory system?
Cilia- traps pathogens
Mucus- moistens air, traps pathogens
Turbinate bones- small bones in the nose that increase SA for blood vessels
Blood vessels- warm incoming air
Describe the lung?
Trachea- has c shaped cartilage, connects to bronchi
Bronchi-branch off of trachea, also have c shaped cartilage
Bronchioles- branch off of bronchi
Alveoli- At end of bronchi
What are some factors of alveoli?
- thin, allow for gas exchange
- surrounded by capillaries, so gas exchange can occur
- Has a lubricating membrane that keeps alveoli moist and from sticking together, in order to increase SA
What are the stages of respiration?
- inhalation/exhalation
2, external respiration (lungs-blood) - Internal respiration (blood-body cells)
- Cellular respiration
What conditions are necessary for a functioning respiratory system?
High SA:V ratio
Moist environment
What are the steps of inhalation? (in sequence order)
- Rib muscles contract—-rib cage moves up and down, diaphragm moves down
- Volume of chest cavity increases, air pressure decreases
- since air pressure is low, air moves into lungs (high to low)
What are the steps of exhalation? (in sequence order)
- rib muscles relax— rib cage moves down and in, diaphragm moves up
- volume of chest cavity decreases, air pressure increases
- Since air pressure is high, air moves out (moves from high to low)
How does the body regulate breathing?
CO2 and O2 Chemoreceptors, which are activated when the medula oblongata, a part of the brain, recognize changes
How do CO2 chemoreceptors work?
- exercise-cells use O2 for cellular respiration
- increase CO2, decreased blood pH
- chemoreceptors detect CO2
- Medulla oblongata detects
- Tells diaphragm and intercostal muscles to work harder
- Decrease CO2 levels, increases blood pH
- Chemoreceptors detect decrease CO2, and stop
What does low blood pH mean?
There is an increase in CO2
How do O2 chemoreceptors work?
- Low O2 - caused by high altitudes/carbon monoxide poisoning
- O2 chemoreceptors detect
- medula oblongata detects
- tells diaphragm and intercostal muscles to breathe more
- increase O2,
- O2 chemoreceptors detect increase, stop production
How does oxygen travel through the blood?
It is transported by
- 99% hemoglobin (More specifically Oxyhemoglobin)
- 1% dissolved in blood plasma
How does CO2 transport through the blood?
- 9 % in the plasma
- 21% in the hemoglobin
- 70% as carbonic acid (!)
How does Co2 travel as carbonic acid throughout the body?
1) CO2 combines with H2O, uses the enzyme carbonic anhydrase, to form H2CO3 ( carbonic acid)
2) H2CO3 is unstable, so it splits into Hydrogen and HCO3 (bicarbonate).
Hydrogen-attaches to hemoglobin, can created CARBAMINOHEMOGLOBIN, which travels to the lungs
Bicarbonate- safely travels to lungs
In the lungs: H + HCO3
turns into
H2O+ CO2 and is finally breathed out
What are some types of waste products?
Ammonia-deamination, dangerous, amino acids
Urea- ammonia+CO2= urea
Uric acid-break down of nucelic acid
How is urine formed?
Urine is formed in the kidneys, more specifically in the nephrons. The steps are as follows:
1. Filtration -filtering blood
-happens at glomerulus (bundle of capillaries)
- Requires high BP
-mincerals+ H2O in nephron
- Blood proteins-stay in blood
2. Reabsorption- reabsorbs useful materials back into blood, occurs at proximal tubule and loop of henle
3. secretion - removal of waste from blood, occurs ar distal tubule
4. reabsorption- reabsorbing more h2o back to blood
- occurs at distal tubule and collecting
duct
Provide a summary of the nephron (In order)
Glomerulus-filtration
bowmans capsule- receives filtrate (stuff that gets through from blood)
proximal tubule- reabsorption (of ions, glucose, amino acids)
Loop of henle (ascending/descending)- reabsorption (of H2O and salt)
Distal tubule- secretion of ions and extra waste
Collecting duct- H2O reabsorption
What does the body do if the pH is too acidic?
keep in mind that H is acids, HCO3 is bases
Reabsorbs more HCO3, secretes more H
What does the body do if pH is too basic?
Reabsorbs more H, secretes more HCO3
How do kidneys regulate pH?
By reabsorbing/reabsorbing certain ions
What are the main functions of the excretory system?
- eliminates waste products
- pH balance
- Water balance
How are wastes removed from the body?
Skin, lungs, and urinary system
What is osmoregulation?
Osmoreguation is maintainign equlibrium of osmotic pressure.
Amount of water reabsorbed from filtrate affects toe main things - volume of blood
- concentration of plasma solutes in blood
If water level in blood changes, so does osmotic pressure
- increase in somotic pressure=more plasma solutes in blood=dehydrated, less h20
- –decrease in osmotic pressure=less solutes in blood=hydrated, more h2o
What are osmoreceptors?
Specialized nerve receptors in the hypothalamus detect change in osmotic pressure
Which hormones are used in osmoregulation?
ADH
- produced by hypothalamus
- AKA antidiuretic hormone
- Increases permeability in cells of collecting duct—allows for more reabsorption of more h2o
- ADH is released when dehydrated
- urine becomes concentrated
Aldosterone
- produced at renal glands
- increase permeability of distal tubule+collecting duct to NA+— more NA reabsorption
- —H2O follows - regulates blood pressure
Explain negative feedback for ADH
- increases osmatic pressure ( dehydrated)
- osmoreceptors detect increase
- pituitary gland releases ADH
- Kidney-increases permeability of distal tube
- increased reabsorption, decreased urine
- decreased osmotic pressure
- osmoreceptors detect decrease in pressure, shuts off
