Resp. Review I
This is the term for the exchange of gases with the external environment.
What is ventilation?
Using Boyle's Law, if lung volume doubles, this is what happens to alveolar pressure.
What is pressure is reduced by half?
List the characteristics of amines and two examples of these hormones.
What are hydrophilic and hydrophilic amino acid derivatives that are made with chemical modifications?
(Dopamine, T3/T4, Epinephrine)
Explain why steroid hormones need transport proteins in the blood.
What are hydrophobic steroids can't dissolve freely in water-based blood, so they require transport proteins; peptide hormones are hydrophilic and dissolve directly in plasma
This process explains why the Hb dissociation curve is sigmoidal rather than linear.
What is cooperativity?
A patient has decreased surfactant production. This is how gas exchange would be affected and why.
What is difficulty for the alveolar expansion, reducing gas exchange?
What are the three mechanisms that control hormonal secretion.
What are
Humoral (blood chemical levels)
neural (direct nervous system stimulation)
hormonal (a hormone triggers release of another)?
Identify the process that would be inhibited if a medication blocked peripheral-type benzodiazepine receptors and what would occur after.
What is cholesterol having the inability to pass the inner mitochondrial membrane, leading to a lack of steroid synthesis?
These are the 5 functions of the respiratory system.
What are: providing oxygen, eliminating CO2, regulating pH, speech production, and defending against foreign bodies?
Carbon dioxide is primarily transported as bicarbonate rather than dissolved gas to limit its toxic effects. This is the chemical process that makes that possible.
What is carbonic anhydrase converting CO2 + H2O into H+ and HCO3-?
This combination of iodinated tyrosines forms T3
What is MIT + DIT = T3?
Explain the processes that would be disrupted if the posterior pituitary gland was removed.
What are
Oxytocin (smooth muscle contraction)
Vasopressin (water loss prevention and vasoconstriction)?
During passive expiration, this mechanism drives air out of the lungs.
What is elastic recoil of the lungs?
A patient is hyperventilating. Using what you know about PCO2 and central chemoreceptors, describe what will happen to their ventilation drive and blood pH over time.
What is PCO2 dropping, reducing H+ concentration, which decreases central chemoreceptor stimulation and slows ventilation, while blood pH rises causing alkalosis?
These are the six hormones released by the anterior pituitary.
What are FSH, LH, TSH, ACTH, prolactin (PRL), and growth hormone (GH)?
A patient with iodine deficiency will have these consequences through the hypothalamic-pituitary-thyroid axis and have this physical effect on the thyroid.
What is low iodine and insufficient T3/T4 synthesis leading to a lack of negative feedback control on TRH and TSH; constant TSH stimulation causes the thyroid gland to hypertrophy (goiter)?
A patient breathes 500ml per breath. This is how much fresh air actually reaches the alveoli.
What is 350ml, because 150ml remains in dead space?
The pneumotaxic and apneustic centers have opposing effects on the DRG. This is what would happen to breathing if only the apneustic center were active.
What is breathing would be prolonged and uncontrolled because the apneustic center continuously stimulates the DRG without the pneumotaxic center to inhibit and limit inspiration?
List the step-by-step pathway of the hypothalamic-pituitary-adrenal axis?
Hypothalamus releases CRH → anterior pituitary releases ACTH → adrenal cortex releases cortisol → increases plasma glucose, fatty acids, and amino acids
Explain the physiological reason that aldosterone changes gene expression, while TSH and GH use second messengers on the plasma membrane.
Aldosterone is hydrophobic and crosses the plasma membrane to enter the nucleus directly, for direct effect on gene expression; TSH and GH are hydrophilic and cannot cross the membrane, so they bind surface receptors and use second messengers to affect the cell.