Week 2 - Acid & Base Balance Flashcards
Define an ionic bond
Complete transfer of e- between atoms.
Type of chemical bond generating 2 oppositely charged ions.
Very strong, difficult to break.
What happens in an ionic bond?
Metal loses e- to become a +ively charged CATION.
Nonmetal accepts e- to become a -ively charged ANION.
Bonds of salts + acids + bases
Salts – Ionic bonds
Acids + bases - Covalent bonds
Purpose of salts vs acids + bases
SALTS
- Structural components
- Electrolyte properties
ACIDS + BASES
- Metabolic control
- Homeostasis
What happens to both salts, acids + bases in water?
They dissociate
Which out of acids + bases are the proton donors + the proton acceptors?
Acids - proton donors
Bases - proton acceptors
What happens when acids dissociate in H20
They release H+.
What is the general formula of what happens to acids + give an example
Acid —> proton + anion (into solution).
HCL —> H+ + Cl-
Give 3 examples of acids in the human body
HCL (for digestion)
Carbonic acid (chemical buffering)
Citric acid (2nd stage of CHO breakdown).
Compare strong acids to weak acids
STRONG vs WEAK
Dissociate completely — Reach equilibrium
Irreversible — Reversible + conc. driven
Give an example of a strong acid
HCL
Give an example of a weak acid
Carbonic acid
What happens when bases dissociate in H20
Release OH-
hydroxyl group
Give the general equation for a base
Base —> Hydroxyl ion + cation
NaOH —> OH- + Na+
What can concentration be shown as?
Moles per litre
What is the potential of hydrogen (pH)?
Quantitive measure of the acidity or alkalinity of a solution.
How is pH calculated
As a -ive logarithm to base 10 of H+ conc in a given solution.
-log(10)[H+]
Define buffering
Chemical + physiological mechanisms that moderate changes in [H+]
What pH does arterial blood have + what can it lead to if it ranges from those values?
7.35-7.45
Acidosis or alkalosis
Properties of chemical buffers
Immediate response
Reversible
Catalysed by enzymes
Properties of physiological buffers
2nd line of defence: Pulmonary/ventilatory + renal systems
How long can renal buffering take
Hours to days
Renal buffering
Renal tubules regulate acidity through complex chemical reactions that restore bicarbonate blood.
Only pathway to eliminate acids other than carbonic acid
Excretion of H+
Urine acidity or a alkalinity refletcs [H+].
How long can ventilatory/pulmonary buffering take
Fast response – important during exercise
Ventilatory/Pulmonary buffering
Changes CO2 conc.
⬆️ H+ stimulates the ventilatory control
⬆️ alveolar ventilation
⬆️ CO2 removal
Equation for when carbonic acid donates a H+
H2CO3 —> H+ + HCO3-
What is the role of a weak base
To mop up H+ so reaction becomes reversible.
What are the possible variations in arterial blood?
PO2
PCO2
pH
Temp
What is one of the factors that regulates ventilation?
Plasma pH
What are the forms of metabolic alkalosis
Diuretics
Overactive adrenal gland
Loss of acids through stomach drainage
What are the forms of respiratory alkalosis
Hyperventilation
What are the forms of metabolic acidosis
Lactic acidosis
Build up of ketones
Kidney malfunction
Lung malfunction
Loss of bases through digestive tract
What are the forms of respiratory acidosis
Hypoventilation
What are the acid-base imbalances caused by intense exercise
Large temp disturbance
Low plasma pH = nausea, headache…
