FPSC MCQs

Arteries carry blood away from the heart under pressure.
Most carry oxygenated blood, with pulmonary arteries as an exception.

Veins return blood to the heart.
Many contain valves that help prevent backflow.

Phloem transports sucrose and other organic nutrients.
Movement can occur toward growing or storage tissues.

Capillary walls are only one cell thick.
This allows diffusion of gases, nutrients, and wastes.

Photosynthesis stores light energy in glucose.
Oxygen is released as a by-product.

Red blood cells contain hemoglobin.
Hemoglobin binds and transports oxygen.

Carbon dioxide supplies carbon for glucose formation.
It enters leaves mainly through stomata.

White blood cells identify and attack pathogens.
Different types act through phagocytosis or immune responses.

Splitting water during photosynthesis releases oxygen.
The gas diffuses out through stomata.

Platelets gather at damaged vessels and activate clotting.
This limits blood loss.

Chlorophyll absorbs mainly blue and red light.
Its green color results from reflected green wavelengths.

Plasma carries cells, nutrients, hormones, wastes, and proteins.
It is mostly water.