Explanation

Polyethene, also known as polyethylene, is a type of plastic.

It is a thermoplastic polymer made from ethylene monomers.

It is commonly used in packaging, plastic bags, and containers.

Explanation

Spores are specialized structures in unicellular organisms, such as bacteria, fungi, and some protists, that enable asexual reproduction without fusion.

Spores are highly resistant to environmental stresses and can germinate into a new individual when conditions are favorable.

Explanation

Halophytes are plants that are adapted to grow in coastal areas with high salt concentrations, such as salt marshes, mangroves, and seashores.

They have specialized structures and physiological adaptations to survive in these saline environments.

Explanation

The speed of sound in air is affected by two main factors:

1. Temperature: As temperature increases, the speed of sound increases. This is because warmer air is less dense, allowing sound waves to travel faster.
2. Humidity: As humidity increases, the speed of sound decreases slightly. This is because water vapor in the air adds mass to the air molecules, making them slightly heavier and slower.

Explanation

Alkenes are a class of unsaturated hydrocarbons that contain one or more carbon-carbon double bonds (C=C).

This double bond is the defining feature of alkenes.

It makes them more reactive than saturated hydrocarbons (alkanes).

Explanation

Farmers were the earliest biotechnologists, as they inadvertently manipulated the genetic makeup of crops and livestock through selective breeding and domestication.

This traditional form of biotechnology dates back thousands of years, long before the discovery of DNA and modern genetic engineering techniques.

Explanation

Genotype refers to the genetic constitution of an individual, which is the specific set of genes and alleles that an individual possesses.

It is the genetic makeup of an individual that determines their traits and characteristics.

Explanation

Chromatin is the chemical material that makes up chromosomes, consisting of DNA, histone proteins, and other non-histone proteins.

It's the complex of DNA and proteins that form the chromosome.

Explanation

Antagonist muscles are pairs of muscles that work in opposite directions to control movement around a joint.

One muscle contracts while the other relaxes, and vice versa.

This opposing action allows for precise control over movement.

Explanation

Chondrocytes are the cells that make up cartilage, a type of connective tissue found in various parts of the body, such as joints, ears, nose, and ribs.

Chondrocytes produce and maintain the cartilage matrix, which consists of collagen and proteoglycans.