Biology Online Quiz

The lungs are the primary organs of the human respiratory system, where the exchange of oxygen and carbon dioxide takes place. While the nose and mouth serve as entry points for air, gas exchange occurs in the alveoli of the lungs.

Among the options, fungi are eukaryotic organisms and are generally much larger than prokaryotic bacteria and acellular viruses. An antibody is a protein molecule, not a living microorganism.

The mammalian heart, including the human heart, consists of four chambers: the right atrium, right ventricle, left atrium, and left ventricle. This structure prevents the mixing of oxygenated and deoxygenated blood.

The primary vegetative parts of a vascular plant are the leaves, roots, and stems. While flowers have petals and some plants have trunks, leaves, roots, and stems are the most universal and fundamental parts of vascular plants.

Cellular respiration breaks down glucose and oxygen to produce carbon dioxide, water, and energy in the form of ATP. The balanced chemical equation yields 6 molecules of carbon dioxide and 6 molecules of water alongside ATP.

The primary function of the digestive system is to break down food into nutrients that the body can absorb for energy, growth, and repair, while expelling indigestible waste.

Fertilization is a process characteristic of sexual reproduction, where male and female gametes fuse to form a zygote. Budding, fragmentation, and fission are all methods of asexual reproduction where offspring arise from a single parent.

Human red blood cells circulate in the bloodstream for an average of about 120 days before they are broken down and recycled by the spleen and liver.

Silk is primarily composed of two proteins: fibroin, which forms the structural core of the fiber, and sericin, which acts as a sticky material surrounding the fibers.

Bananas are widely known for being an excellent dietary source of potassium (K). This essential mineral helps regulate fluid balance, nerve signals, and muscle contractions throughout the body.