Question Library

Abiotic factors are the non-living physical and chemical elements in an environment, such as temperature, water, light, and soil. Temperature directly influences metabolic rates, geographical ranges, survival, and distribution of living organisms. Competition, predation, and parasitism are biotic factors because they involve interactions between living organisms

Discontinuous variation involves clear-cut, sharp differences among individuals for a given trait with no intermediate grades or in-between forms (for example, blood groups like A, B, AB, and O, or tongue-rolling).

The thoracic vertebrae are the 12 vertebrae (T1–T12) form the back part of the rib cage and have special costal facets that articulate with the ribs, providing attachment points for muscles and structures involved in respiration.

The process of breaking down food substances to release energy within the body is called respiration (or cellular respiration).

Population Density = \(\frac{Total population}{Total Area}\) Total population = 2000 butterflies Total Area = Area of rectangular field = length x width = 20 x 10 = 200m\(^2\) Population Density = \(\frac{Total population}{Total Area}\) = \(\frac{2000}{200}\) = 10 butterflies/m\(^2\)

Ducks have a specialized bill equipped with fine, comb-like structures along the edges called lamellae (which look like serrated teeth). When a duck scoops up muddy water, it uses its tongue to push the water out through these serrated edges. The lamellae act as a colander, trapping small plants, seeds, insects, and tiny aquatic animals inside the mouth while letting the water drain away. Hence, the correct answer is sieving food from water - option A

The pigment carrying oxygen in the blood is called haemoglobin. This iron-rich protein is found inside red blood cells and is responsible for giving blood its red color while transporting oxygen from your lungs to the rest of your body.

The thoracic vertebrae are found in the middle and upper back (the thoracic region of the spinal column or vertebral column), located between the cervical (neck) spine above and the lumbar (lower back) spine below. Thoracic vertebrae are widely characterized by a long, pointed neural spine that angles sharply downward and backward. (See diagram above)

A whirling hygrometer is used to measure relative humidity and dew point in the atmosphere.

The Rod-like or thread-like structures in the nucleus of a cell composed of DNA and proteins are called the chromosomes. They house and carry the genes.

Haemophilia is a genetic bleeding disorder caused by a deficiency or complete absence of specific blood clotting proteins (factors). Without these proteins, the blood cannot clot properly, leading to prolonged bleeding.

The parts labelled: I: Root cortex (parenchyma cells that transport water from the epidermis to the inner vascular tissue). II: Endodermis / Vascular cylinder (regulates the entry of water and minerals into the xylem). III: Root hair (long, narrow extensions of the root epidermal cells that provide a large surface area to maximize water absorption from the soil). IV: Cortex cell wall / intercellular pathway (involved in the apoplastic or symplastic transport of water). The structure that absorbs water from the soil is labelled III, which represents a root hair cell.

A sea is a saltwater environment with a high salt concentration, making it a true marine habitat.

High temperatures during the day and very cold temperatures at night occur because dry desert air lacks moisture (humidity and clouds) to trap heat after sunset.

Gaseous exchange in unicellular organisms (such as Amoeba and Paramecium) takes place through simple diffusion across the general body surface or cell membrane. Because these organisms consist of only a single cell and have a large surface area relative to their volume, the body surface alone provides enough area for oxygen and carbon dioxide to move in and out.