Respiratory & Excretory Quiz Flashcards
Main Function of the Respiratory System
- Ensure that oxygen is brought to each cell in the body and that carbon dioxide can leave each cell & be removed from the body.
- Respiration is the general term to describe this process
Respiratory Surface Area
- The area must be large enough for the exchange of oxygen & carbon dioxide to occur at a fast enough rate to meet the body’s needs.
Requirement For Respiration
Huge Respiratory Surface Area
Moist Environment
Stages In Respiration
Breathing
External Respiration
Internal Respiration
Cellular Respiration
Moist environment
Respiration MUST take place in a moist environment so that oxygen & carbon dioxide are dissolved in water
External Respiration
- Exchange of oxygen & carbon dioxide between the air and the **blood*
Takes place in the lungs
Breathing
- Involves inspiration (Breathing in/ Inhaling) & expiration (Breathing out/ exhaling)
Lower Respiratory Tract
Bronchi–> Bronchioles–> Alveoli
–> Lungs –> Pleural Membrane
Internal Respiration
Exchange of oxygen & carbon dioxide between the body’s tissue (Body cells) & the blood
Takes place within the body
Cellular Respiration
- A chemical reaction inside the cells using oxygen and nutrients to get energy
Upper Respiratory Tract
Nasal Passages –> Pharynx–> Epiglottis –> Larynx –> Trachea
PATH OF AIR:
Air enters through the nose & mouth
Nasal Passages
Warm, moisten and clean upcoming air
Pharynx
A.K.A. Throat
The passageway for air into the respiratory system
Glottis
The opening of the trachea
Epiglottis
A flap that makes sure the food doesn’t go into your lungs & air does go into your lungs, when a person swallows the epiglottis closes over the glottis
Trachea
A.K.A. Windpipe
Air moves down here after passing through the larynx.
Has a C-shaped cartilage rings that give it structure
Branches into TWO smaller passageways.
Larynx
A.K.A. Voice Box
Made of cartilage contains vocal cords
Pleural Membrane
Each lung is surrounded by a thin, double-layered membrane called the Pleural Membrane.
Prevents friction between the lungs and the chest walls during breathing.
Helps create a negative pressure within the pleural cavity which keeps the lungs inflated and allows them to expand smoothly as the chest cavity enlarges during inhalation..
Protects the lungs
Maintains lung position.
Bronchi
The smaller passageways that the trachea separated into
Bronchi is PLURAL, Bronchus is SINGULAR
Enter the RIGHT & LEFT lungs
Bronchioles
Each bronchus subdivides into smaller and finer tubes called bronchioles within each lung
Lobes
Each lung is divided into regions called lobes
Each lobe is made of many lobules that extend from each bronchiole
3 lobes on the RIGHT lung
2 lobes on the LEFT lung
Layers of the Pleural Membrane
OUTER LAYER: Attaches to the inside of the chest wall
INNER LAYER: Attaches to the lung
INBETWEEN FLUID: Fills the space between so that they attach together
This allows the lungs to expand & contract with chest movement
Alveoli
Each bronchiole ends in a cluster of tiny sacs
(SINGULAR: Alvelous)
This is where gas exchange occurs
Each alveoli is covered by a membrane called the alveolar wall
The alveolar wall is one cell thick and is surrounded by a network of capillaries
Inspiration (Inhalation)
- Intercostal muscle contract
- Diaphragm moves DOWN (contracts)
- The rib cage moves up & outwards
- The volume of the thoracic cavity increases
- Air pressure in the lungs decreases causing air to move INTO the lungs
Expiration (Exhalation)
- Intercostal muscles relax
- Diaphragm moves UP (Relax)
- Rib cage moves down & inward
- The volume of the thoracic cavity decreases
- Air pressure in the lungs increases causing air to move OUT of the lungs
External Respiration
Occurs in the LUNGS
Gases are exchanged between the alveoli and the blood in the capillaries
Structure for Gas Exchange
Walls of the alveoli & the capillaries each are one cell thick, which allows gases to diffuse through their membrane
How does air move from:
Air moves from HIGH-pressure to LOW-pressure
Chemoreceptors
A specialized nerve recpetor that is sensitive to specific chemicals
Carbon dioxide LOWERS the pH of the blood (Making it MORE acidic)
This is detected by the chemoreceptors in your brain which sends signals causing you to breathe deeper
INCREASE in carbon dioxide = INCREASE Breathing Rate.
What Regulates Breathing
Carbon Dioxide regulates breathing NOT oxygen.
How Gases are Exchanged
- Most of the oxygen & carbon dioxide exchange is done by simple diffusion (Movement from HIGH concentration —> LOW concentration)
- About 30% of the oxygen transfer happens by facilitated diffusion:
- Protein-based molecules in the alveoli “carry” oxygen across the membrane
- This DOES NOT require energy because it is still with the concentration gradient
- This is done to SPEED UP gas exchange
- This DOES NOT require energy because it is still with the concentration gradient
- Protein-based molecules in the alveoli “carry” oxygen across the membrane
Internal Respiration
- After the gas exchange between the capillaries & alveoli, the blood goes back to the heart and is then pumped into the body
- Gases are then exchanged between the blood and cells
Blood –> Body Tissues
Gas Transportation (Oxygen)
~99% of the oxygen is carried in the red blood cell by hemoglobin
This is called “OXYHEMOGLOBIN”
The rest of the oxygen is dissolved in the bloodstream
Gas Transportation (Carbon Dioxide)
- Slightly less than 1/4 of the Carbon dioxide is carried in the blood by hemoglobin- which forms carbaminohemoglobin
- ~7% is carried in the plasma
- ~70% is dissolved & carried in the blood as bicarbonate into ($HCO_3^-$)
- Carbonic acid $(H_2CO_3)$ is formed in the blood when a carbon dioxide molecule $(CO_2)$reacts with a water molecule $(H_2O)$
- $CO_2 +H_2O = H_2CO_3$
- The carbonic acid breaks down into a hydrogen ion $(H^+)$ and a bicarbonate ion – which occurs in red blood cells
- The $(H^+)$ combines with the hemoglobin and the bicarbonate ion diffuses out of the red blood cells into the plasma, which is carried to the lungs
- When the blood reaches the lungs the whole process is reversed to form carbon dioxide and water
Spirometers
Measure the amount of air that moves in and out of the lungs
Spirograph
A graph that measures
Tidal Volume, Inspiratory Volume, Expiratory Volume, Vital Capacity, Residual Volume
Tidal Volume
- The volume of air that is inhaled and exhaled in a normal breathing movement at rest (Breathing normally)
Inspiratory Reserve Volume
An additional volume of air that can be taken into the lungs beyond tidal/regular
Expiratory Reserve
- The additional volume of air that can be forced out of the lungs beyond tidal
Vital Capacity
- Calculated by:
- Tidal volume + Inspiratory Reserve Volume + Expiratory Reserve Volume
Residual Volume
Amount of gas that remains in the lungs even after full exhalation
Nephron
Filtering units within the kidney
There are approximately 2 million of them
Renal Vein
Carries blood AWAY from the kidenys that has been filtered & has minimal waste
Renal Arteries
Carries blood TO the kidneys that are filled with waste and need to be cleaned
Ureter
Tubes that carry urine from the kidneys to the bladder
Bladder
Stores urine
Urethra
Tube that carries urine from the bladder out of the body
Kidneys
Filters blood so that waste can be removed
Help to regulate blood pH
The major metabolic waste products are carbon dioxide, sodium, chloride, urea & uric acid
Ammonia
Produced as a waste product during metabolism
Very toxic so the liver immediately converts it to less toxic waste products that ultimately form urine
Uric Acid
Forms from the breakdown of nucleic acids (DNA & RNA)
Urea
Forms from the breakdown of the amino acid (PROTEIN)
Sections of the Kidney
Renal Pelvis
Cortex
Medulla
Renal Pelvis
Receives urine before sending it to the ureters
Cortex
The OUTER layer of the kidney, UPPER position of the nephron
Medulla
The INNER layer of the kidney, a LOWER portion of the nephron
Renal Vein
Takes CLEAN blood from the kidney to the heart
Renal Artery
Takes DIRTY blood AWAY from the heart TO the kidney
What are the 4 processes involved in the formation of Urine?
Glomerule filtration, Tubular reabsorption, tubular secretion, Water reabsorption
Afferent arteriole
A small branch of the renal artery that carries blood to the glomerulus
Efferent Arteriole
A small branch of the renal artery that carries blood AWAY from the glomerulus to the capillaries
Glomerular Filtration
Move water & solutes NOT proteins & blood cells from the plasma into the nephron.
Formation of urine STARTS here.
Forces some of the water & dissolved substance in the blood plasma from the glomerulus into the Bowman’s Capsule
2 Things that allow this to happen:
Permeability of the capillaries of the glomerulus.
Higher Blood Pressure
Filtrate
The filtered fluid
Permeability of the Capillaries of the Glomerulus
- The capillaries of the glomerulus have many pores in the tissue walls which allow water & dissolved substances to easily pass through BUT are small enough that proteins & blood cells can not enter.
Higher Blood Pressure
- The Blood pressure in the glomerulus is 4x greater than the rest of the body to force blood through for filtration
Tubular Reabsorption
Removes useful substances such as sodium from the filtrate and RETURNS them into the blood for reuse by body systems
Recovery of substances in the Proximal Tubule
- Approx 65% of the filtrate that passes through the entire length of the proximal tubule is reabsorbed and returned to the body
- Cells of the proximal tubule have lots of mitochondria
The majority of glucose is reabsorbed in the PROXIMAL TUBULE
Loop of Henle in the Proximal Tubule
- Function is to reabsorb water and ions from the glomerular filtrate
- The deeper portion of the loop of Henle enters a salty environment in the medulla
- The descending limb is permeable to water and only slightly permeable to ions
- The salty environment draws water out through osmosis leaving a high concentration of $Na^+$ at the bottom of the loop
- When the tubule goes around the bend and ascends up the permeability changes
- Becomes impermeable to water and slightly permeable to solutes causes sodium ions to diffuse from the filtrate and pass into blood vessels
- At the thick-walled portion of the ascending limb, sodium ions are moved out of the filtrate by active transport
- This does two things:
- Helps replenish the salty environment of the medulla
- Makes the filtrate less concentrated than the tissues and blood in the surrounding cortex tissue
Tubular Secretion
Moves wastes & excess substances from the blood into the filtrate
Tubular Reabsorption & Secretion in the Distal Tubule
- Active reabsorption of the sodium ions from the filtrate in the kidneys depends on the needs of the body
- Passive reabsorption of negative ions such as chloride occurs by electrical attraction
- Reabsorption of ions decreases the concentration of the filtrate, which causes water to be reabsorbed by osmosis
- Potassium (K+ ) are actively secreted into the distal tubule from the bloodstream
- Hydrogen ions (H+ ) are also actively secreted in order to maintain pH of the blood
- Other substances that happen to be in the body that are not naturally there (such as different medications) are secreted into the distal tubule
Water Reabsorption
Removes water from the filtrate and returns it to the blood for reuse by the body systems
Reabsorption from the collecting Duct
- Collecting duct extends deep into the medulla and the concentration of ions in the medulla increases (due to active transport of ions from the ascending limb of the loop of Henle)
- This causes passive reabsorption of water from the filtrate in the collecting duct by osmosis
Urine
- If a person is dehydrated the permeability to water in the distal tubule and collecting duct is increased so that more water is reabsorbed into the blood to conserve water in the body
- Reabsorption of water in the collecting duct causes the filtrate to be about four times as concentrated by the time it exits the duct
- Filtrate (which is now ~1% of the original filtrate volume) is now called urine and leaves the body
Osmorecpetors
Cells that are sensitive to osmotic pressure in the blood and surrounding extracellular fluids.
Most are found in the hypothalamus
Dehydrated
Blood plasma is too concentrated (You are DEHYDRATED)
Osmotic pressure INCREASES
This causes the osmoreceptors in your hypothalamus to send a signal to your pituitary gland (another part of your brain) which releases the hormone ADH (antidiuretic hormone)
Hydration
When blood plasma is too dilute (Too much water and not enough solute) the osmotic pressure DECREASES.
This causes the osmoreceptors in your hypothalamus to send a signal to stop or decrease the release of ADH
Increase in ADH
ADH travels to your kidney where it INCREASES the permeability of the distal tubule and collecting duct allowing more water to be reabsorbed in the blood
Decrease in ADH
When ther is too much water the osmoreceptors in your hypothalamus to send a signal to stop or decrease the release of ADH
- Distal tubule and collecting duct become less permeable to water and MORE water is excreted through urine
Maintaining Salt Balance
- Controlled by the hormone Aldosterone
- If the $Na^+$ concentration drops:
- Aldosterone stimulates the distal tubules and collecting ducts to reabsorb Na+
- This leads to passive reabsorption of chloride ions and water
- Aldosterone stimulates the distal tubules and collecting ducts to reabsorb Na+
- Aldosterone also stimulates the section of potassium ions into the distal tubules and collecting ducts if the concentration of potassium ions in the blood is too high
Maintaining pH
- pH of body fluids is about 7.4
The body can maintain this by:- Acid-base buffer system in the body by adding/removing hydrogen ions
- Changes to breathing rate – changes carbon dioxide levels
- Kidney’s controlling pH by excreting $H^+$ and reabsorbing $HCO_3^-$ [Bicarbonate ions]
Dialysis
Dialysis is a treatment that acts like an artificial kidney to clean your blood.
Diabetes Mellitus
CAUSE:
Low levels of insulin produced
by the pancreas, leading to
HIGH blood sugar
SYMPTOMS:
HIGH concentration of glucose
in the urine, frequent urination
Bright’s Disease (A.K.A. Nephritis)
CAUSE:
Inflammation of the nephron.
The Nephron can become
permeable to large solutes like
proteins or even blood parts
SYMPTOMS:
Proteins in Urine, Frequent
urination
Kidney Stone
CAUSE:
Development of crystalline
the formation called the kidney
stones
(Usually formed due to excess
calcium)
SYMPTOMS:
Extreme pain
Urinary Tract Infection (UTI)
CAUSE:
Bacterial or Viral infection
If the BLADDER is involved, it
is called CYSTITIS
If the URETHRA is involved
URETHRITIS
SYMPTOMS:
Painful burning secretion during
urination, feeling as if you need
to pee even if you DO NOT.
Bloody or brown urine
Renal Tubular Acidosis
CAUSE:
Accumulation of acid in the
BODY, due to a failure of the
kidney to properly filter blood
SYMPTOMS:
Tired, muscle weakness can lead
to kidney stones, urine has a
very HIGH pH (Very BASIC)
