Science is the section that separates proficient from advanced scores. About 32 of the 44 scored science items are anatomy & physiology, so that is where your prep hours should live.
Anatomy & physiology by system
Cardiovascular
Know the four chambers, the four valves, and the exact path of blood. Understand the difference between the pulmonary and systemic circuits. Be able to name what the SA and AV nodes do.
Respiratory
Trachea → bronchi → bronchioles → alveoli. Gas exchange happens across the alveolar-capillary membrane. Know inspiration vs expiration mechanics and the role of the diaphragm.
Renal
The nephron is the workhorse. Filtration in the glomerulus, reabsorption in the PCT and loop of Henle, secretion in the DCT. Aldosterone and ADH regulate reabsorption downstream.
Nervous
CNS = brain and spinal cord. PNS = everything else. Sympathetic is fight-or-flight, parasympathetic is rest-and-digest. Know the lobes of the brain and one function each.
Endocrine
Hormones move slowly through blood; nerves move fast. Memorize the pituitary (master gland), thyroid (metabolism), adrenals (stress), and pancreas (insulin/glucagon).
Biology
- DNA replication is semi-conservative.
- Transcription happens in the nucleus, translation in the cytoplasm at the ribosome.
- Mitosis: PMAT (prophase, metaphase, anaphase, telophase).
- Punnett squares: know monohybrid crosses and how to calculate probability.
Chemistry
- Atomic number = protons. Mass number = protons + neutrons.
- Ionic bond = metal + nonmetal (transfer). Covalent = two nonmetals (share).
- Acids donate H⁺. Bases accept H⁺.
- Balanced equations conserve atoms on both sides.
Scientific reasoning
Independent variable is what you change. Dependent is what you measure. Control is what you keep the same. If a question shows you a graph, spend five seconds identifying the axes before you read the answer choices.
