Combined Science Flashcards

What is an ionic bond?

Answer: The electrostatic attraction between oppositely charged ions formed by the transfer of electrons from a metal to a non-metal

Ionic bonding occurs when a metal atom transfers electrons to a non-metal atom, forming positive and negative ions. The strong electrostatic attraction between these ions constitutes the ionic bond.

What is the function of white blood cells in the immune system?

Answer: To defend the body against pathogens by producing antibodies, engulfing bacteria (phagocytosis), and producing antitoxins

White blood cells (leukocytes) protect the body in multiple ways: phagocytes engulf and digest pathogens, while lymphocytes produce specific antibodies that target and neutralise particular pathogens.

What is the relationship between speed, frequency, and wavelength of a wave?

Answer: v = f × λ, where v is speed, f is frequency, and λ is wavelength

The wave equation v = fλ relates speed (m/s), frequency (Hz), and wavelength (m). This applies to all waves including sound, light, and water waves.

What is the difference between a series and parallel electrical circuit?

Answer: In series, components are connected end-to-end (same current); in parallel, components are connected across each other (same voltage)

In series: one path for current (same I throughout), voltages add up. In parallel: multiple paths (same V across branches), currents add up. Parallel circuits keep working if one branch breaks.

What is the greenhouse effect and how does it relate to climate change?

Answer: Greenhouse gases (CO₂, CH₄) trap heat radiation from Earth's surface, warming the atmosphere; excessive emissions intensify this effect causing global warming

The greenhouse effect is natural and necessary. However, increased emissions of CO₂ (from burning fossil fuels) and CH₄ (from agriculture) enhance this effect, leading to global warming and climate change.

What is the structure and function of the human heart?

Answer: A four-chambered muscular organ that pumps oxygenated blood to the body (left side) and deoxygenated blood to the lungs (right side)

The heart has four chambers: right atrium and ventricle (pump deoxygenated blood to lungs) and left atrium and ventricle (pump oxygenated blood to the body). Valves prevent backflow.