1Formulas and methods
Biology for nursing entrance exams
Method
- Name the topic of the question: cell parts, transport, division, DNA and protein synthesis, inheritance, biomolecules, microorganisms or experimental design.
- Recall the key rule: A–T and G–C, diffusion from high to low, water moves towards more solute, mitosis keeps and meiosis halves the chromosome number.
- For crosses, write the parents’ genotypes, list the gametes and fill a Punnett square before counting.
- For experiments, label the independent, dependent and controlled variables, and ask whether the evidence supports or only suggests the conclusion.
- Check each option against the question asked, not just whether it is a true statement.
Chemistry for nursing entrance exams
Method
- Identify what is given and asked: particles, a formula, a state change, a concentration, a pH or a mass.
- Use the periodic table: the atomic number gives protons, the group gives valence electrons and the usual ion charge.
- Balance equations with coefficients only, element by element, oxygen and hydrogen last.
- For amounts, go mass → moles → mole ratio → moles → mass, and for solutions use M = mol/L and C₁V₁ = C₂V₂.
- Remember that pH is logarithmic: one unit is a factor of 10.
2Practice problems
1.Human anatomyMedium
Which part of the brainstem contains the main cardiovascular and respiratory centres?
- APons
- BMidbrain
- CMedulla oblongata
- DCerebellum
2.Human anatomyHard
A patient has a drooping eyelid, a dilated pupil and an eye that rests "down and out". Which nerve is most likely damaged?
- AAbducens nerve (VI)
- BTrochlear nerve (IV)
- COculomotor nerve (III)
- DOptic nerve (II)
3.Human physiologyMedium
The Frank–Starling mechanism describes that:
- AContractility falls when temperature rises
- BStroke volume rises when ventricular filling increases
- CThe atria contract after the ventricles
- DHeart rate rises when arterial blood pressure falls suddenly
4.Human physiologyHard
Which adaptation develops over days to weeks at high altitude?
- AA fall in haematocrit
- BIncreased renal bicarbonate retention
- CLower ventilation to save oxygen
- DHigher erythropoietin levels and more red blood cells
5.Biology for nursing entrance examsMedium
Why is a buffer system important in blood?
- AIt makes the blood clot faster
- BIt carries oxygen to the tissues
- CIt raises the blood glucose level
- DIt resists changes in pH
6.Biology for nursing entrance examsHard
Why are there usually far fewer top predators than herbivores in an ecosystem?
- ATop predators need less energy than herbivores
- BHerbivores eat the young of top predators
- CTop predators reproduce faster than herbivores, so they die sooner
- DEnergy is lost at each step, leaving little for the top level
7.Chemistry for nursing entrance examsMedium
What are hydrogen bonds?
- AAttractions between a hydrogen on one molecule and an O, N or F atom on another
- BCovalent bonds between two hydrogen atoms in H₂
- CBonds inside the nucleus of hydrogen
- DIonic bonds between hydrogen ions and metals
8.Chemistry for nursing entrance examsHard
An element has the electron arrangement 2, 8, 8, 2. Where is it on the periodic table?
- AGroup 2, period 4
- BGroup 8, period 2
- CGroup 2, period 2
- DGroup 4, period 2
3Solutions
1.Human anatomy
Answer: C · Medulla oblongata
Why this is the answer
The medulla oblongata contains the vital centres that regulate heart rate, blood pressure and breathing rhythm.
2.Human anatomy
Answer: C · Oculomotor nerve (III)
Why this is the answer
The oculomotor nerve supplies most eye muscles, levator palpebrae and the pupil constrictor. Lesion leaves lateral rectus and superior oblique unopposed, so the eye goes down and out.
C · Oculomotor nerve (III)
3.Human physiology
Answer: B · Stroke volume rises when ventricular filling increases
Why this is the answer
Greater end-diastolic volume stretches the myocardium, which increases the force of contraction and the stroke volume, matching output to venous return.
B · Stroke volume rises when ventricular filling increases
4.Human physiology
Answer: D · Higher erythropoietin levels and more red blood cells
Why this is the answer
Hypoxia stimulates EPO and red cell production, raising oxygen-carrying capacity. Hyperventilation causes alkalosis, which the kidneys compensate by excreting bicarbonate.
D · Higher erythropoietin levels and more red blood cells
5.Biology for nursing entrance exams
Answer: D · It resists changes in pH
Why this is the answer
Buffers, such as the bicarbonate system, take up or release hydrogen ions to keep blood pH within a narrow range. Even small changes can disturb enzymes and other proteins.
D · It resists changes in pH
6.Biology for nursing entrance exams
Answer: D · Energy is lost at each step, leaving little for the top level
Why this is the answer
Only about a tenth of the energy at each level passes to the next, because much is used for movement and lost as heat. After several levels, the energy available supports only a small number of top predators.
D · Energy is lost at each step, leaving little for the top level
7.Chemistry for nursing entrance exams
Answer: A · Attractions between a hydrogen on one molecule and an O, N or F atom on another
Why this is the answer
A hydrogen bond is a fairly strong attraction between molecules, not a bond within one. It explains water's high boiling point and holds DNA's base pairs together.
A · Attractions between a hydrogen on one molecule and an O, N or F atom on another
8.Chemistry for nursing entrance exams
Answer: A · Group 2, period 4
Why this is the answer
Four occupied shells means period 4, and 2 outer electrons means group 2. This element has 20 electrons, so it is calcium.