What is the function of ribosomes?
Protein synthesis.
Which blood vessels carry blood back to the heart?
Veins.
What is a genotype?
The genetic makeup of an organism.
What are pathogens?
Microorganisms that cause disease.
Which organ regulates blood sugar by producing insulin?
Pancreas.
Why are lysosomes sometimes called the “suicide bags” of the cell?
They contain enzymes that can digest the cell if released.
Why is oxygenated blood bright red while deoxygenated blood is darker?
Oxygen binding to hemoglobin changes its color.
What is the difference between homozygous and heterozygous individuals?
Homozygous has two identical alleles, heterozygous has two different alleles.
Why do doctors prescribe antibiotics for bacterial infections but not viral infections?
Viruses lack cell walls/metabolism that antibiotics target.
Why does a person with kidney failure often need dialysis?
because their kidneys can’t filter wastes and excess water from blood.
Why do muscle cells have more mitochondria than skin cells?
They need more ATP for constant contraction and energy-demanding activity.
Explain why breathing rate increases during exercise.
More CO₂ and lactic acid are produced, stimulating faster breathing to remove CO₂ and supply oxygen.
Explain why two parents with normal vision can have a son who is colorblind.
Mother is a carrier (XᴺXᶜ), father normal (XᴺY). Son inherits Xᶜ from mother and Y from father → colorblind.
How does vaccination protect against future infection?
By creating memory B and T cells for faster immune response.
Why do people with asthma have difficulty breathing during an attack?
Airways constrict and produce mucus, reducing airflow to lungs.
If a cell is unable to produce enough ATP, which organelles might be defective and why?
Mitochondria, because they are the site of aerobic respiration.
If the SA node in the heart stops working, what happens and why?
The heart loses its natural pacemaker function, leading to irregular or stopped heartbeat.
How could nondisjunction during meiosis cause Down syndrome?
Failure of chromosome 21 to separate leads to trisomy 21 in gametes → child has three copies.
Why is antibiotic resistance a growing global problem?
Overuse/misuse allows resistant bacteria to survive and spread, reducing effectiveness of treatments.
How does a malfunctioning thyroid gland affect metabolism?
Hyperthyroidism → too much thyroxine → high metabolism; hypothyroidism → too little thyroxine → slow metabolism.
A scientist treats animal cells with a toxin that blocks protein transport from the rough ER to the Golgi apparatus. Predict at least two consequences for the cell.
Proteins won’t be processed/modified, secretory proteins (e.g. hormones, enzymes) won’t be exported, leading to disrupted cell communication and function.
Why would a blockage in the coronary arteries be more dangerous than in a vein of the leg?
Coronary arteries supply oxygen to the heart muscle itself—blockage causes myocardial infarction (heart attack), which can stop the heart entirely.
A father has blood group AB and the mother has blood group O. What possible blood groups could their children have? Explain.
Only A or B. Father (IAIB) × Mother (ii) → children can be IAi (A) or IBi (B), but never AB or O.
compare how tuberculosis (TB) and HIV weaken the body, and explain why a patient with both infections is at even higher risk.
TB damages lungs, HIV destroys helper T-cells. Together, they weaken immunity and respiratory health severely, making it harder to fight infections.
Explain how high blood pressure can eventually lead to both kidney failure and stroke.
High pressure damages kidney capillaries (reducing filtration) and weakens/damages cerebral arteries (leading to rupture or clot → stroke).