Science Discovery Quiz: Physics, Chemistry & Biology

Normal blood pH is tightly regulated between 7.35 and 7.45, which is slightly alkaline. This narrow range is critical for proper enzyme function and cellular processes. Option A (7.1-7.2) is too acidic and would indicate acidosis. Option D (7) is neutral pH, not physiological pH. Blood must maintain this specific alkaline range for survival.

Normal blood pressure is 120/80 mmHg. High blood pressure (hypertension) is generally defined as 140/90 mmHg or above. Low blood pressure (hypotension) is typically diagnosed through symptoms of inadequate blood flow rather than a fixed number, though values below 90/60 mmHg often indicate hypotension. Option B correctly captures the clinical thresholds.

Blood composition is approximately 55% plasma and 45% blood cells (red blood cells, white blood cells, and platelets). Since plasma is 90% water, and plasma makes up 55% of blood, water constitutes roughly 50% of total blood volume. The 55% figure represents the plasma fraction itself.

Laika, a Soviet stray dog, became the first living creature to orbit Earth aboard Sputnik 2 on November 3, 1957. While she did not survive the mission, she pioneered living space travel. Later animals were sent into space, but Laika was first.

The Apollo missions (especially Apollo 11, 12, 14-17) landed astronauts on the Moon and left behind descent stages, scientific instruments, flags, and personal items - collectively described as expensive rubbish. The Voyager and Pioneer were deep space probes, while Sputnik was an early Soviet satellite.

Saturn's rings are composed primarily of ice particles (90-95% ice), ranging from tiny grains to house-sized chunks, along with smaller amounts of rocky dust and chemical compounds. They are not gases, clouds, wind, or storms, but solid material orbiting the planet.

Jupiter has the most confirmed moons (95 as of 2024), followed by Saturn (146 confirmed). This is due to Jupiter's massive gravitational field capturing and retaining numerous small moons. Earth has one moon, while Neptune has 14 known moons.

Skylab was the heaviest object launched into space at approximately 77 metric tons (169,000 lbs). It was significantly heavier than the Salyut space stations and far exceeded the mass of satellites or typical spacecraft like Luna. The U.S. space station remained in orbit from 1973 to 1979.

Quarks are fundamental particles that cannot be broken down into smaller components - they are elementary constituents of matter. Electrons are also fundamental, but protons and neutrons are composite particles made of quarks. Option A incorrectly groups fundamental (electron) with composite (proton) particles, while B is composite.

John Dalton proposed the first modern atomic theory (1803), establishing the concept that all matter is composed of atoms. J.J. Thomson discovered the electron (1897) and proposed the plum pudding model, while Rutherford discovered the proton and nuclear structure (1911). Dalton's foundational work came first.

J.J. Thomson discovered the electron in 1897 through cathode ray tube experiments, demonstrating the existence of negatively charged subatomic particles. This led to his plum pudding model of the atom. Thomson did not discover the atom (Dalton), proton (Rutherford), or neutron (Chadwick).

Ernest Rutherford discovered the proton in 1917-1919 through experiments with nitrogen gas, identifying hydrogen nuclei as a fundamental component of all atomic nuclei. This followed his earlier gold foil experiments that revealed the nucleus. Einstein developed relativity theory, Maxwell formulated electromagnetic theory, and Dalton proposed atomic theory (but didn't discover the proton).

James Chadwick discovered the neutron in 1932. The neutron is a chargeless (neutral) and massive subatomic particle found in atomic nuclei. J.J. Thompson discovered the electron, and John Dalton proposed atomic theory.

Blaise Pascal invented the Pascaline in 1642, an early mechanical calculator that could perform addition and subtraction. It was one of the first calculating machines and used a geared wheel mechanism. His work laid groundwork for future computing devices.

Baking soda's chemical name is sodium bicarbonate (NaHCO3), a white crystalline compound used as a leavening agent in baking. Sodium carbonate is washing soda, while sodium chloride is table salt. The bicarbonate releases CO2 when heated, causing dough to rise.

László Bíró, a Hungarian journalist, patented the first successful ballpoint pen in 1938. The design used a tiny ball that rolled to distribute ink as it moved across paper. His brother György, a chemist, helped develop the viscous ink formula that didn't smudge.

William Harvey demonstrated in 1628 that blood circulates continuously through the body, pumped by the heart. His work 'De Motu Cordis' overturned the prevailing Galenic theory. Edward Jenner developed smallpox vaccine, while Joseph Lister pioneered antiseptic surgery.