Explanation

HIV (Human Immunodeficiency Virus) was first identified in 20 May 1983

By researchers Luc Montagnier and Françoise Barré-Sinoussi in France.

Their discovery linked HIV to AIDS, leading to significant advancements in understanding and managing the disease.

Explanation

H5N1 is a type of influenza virus

Causes a highly infectious

Also known as avian influenza.

Occurs mainly in birds, is highly contagious among birds, and can be deadly, especially in domestic poultry

Explanation

Wilhelm Johannsen coined the term “gene” in 1909

Johannsen created "gene" from the Greek word genos, meaning "birth" or "race".

He  was a Danish botanist and geneticist

 He is best known for coining the terms gene, phenotype, and genotype, and for his 1903 "pure line" experiments in genetics.

Born: 3 February 1857, Elsinore, Denmark

Died: 11 November 1927 (aged 70) Copenhagen, Denmark

Explanation

The medulla oblongata is located in the brainstem.

It regulates involuntary functions such as heartbeat, breathing, and blood pressure.

The cardiac center within the medulla controls heart rate and force of contraction.

It receives signals from the autonomic nervous system (sympathetic and parasympathetic).

Explanation

Magma is molten rock beneath the Earth’s surface.

When it erupts through a volcano or reaches the surface, it is called lava.

Lava cools and solidifies to form igneous rocks.

The flow of lava can create volcanic landforms like lava plateaus and volcanic cones.

Lava temperature ranges from 700°C to 1,200°C, depending on its composition.

Explanation

Explanation

Blood circulation rate in human arteries varies, fastest in the aorta (around 30-40 cm/s) 

In capillaries, the speed drops significantly to allow nutrient and gas exchange.

Blood velocity is highest in arteries, moderate in veins, and slowest in capillaries.

Proper circulation speed ensures efficient delivery of oxygen and nutrients throughout the body.

Explanation

Chromosomes are thread-like structures found in the nucleus of a cell.

They carry genetic information in the form of DNA.

Humans have 46 chromosomes (23 pairs) in each cell.

Chromosomes determine hereditary traits passed from parents to offspring.

They play a key role in cell division, growth, and reproduction.

Explanation

Bile is produced by the liver but stored in the gall bladder.

The gallbladder releases bile into the small intestine when fatty foods are present.

Bile helps in the digestion and absorption of fats.

It also neutralizes stomach acid entering the small intestine.

Gall bladder function is crucial for efficient fat metabolism in the body

Explanation

An oasis is a fertile area found in a desert.

It has a natural source of water, such as springs or underground water.

The presence of water allows plants and trees to grow.

Oases often support human settlements and agriculture.

They are crucial resting points for travelers and caravans in deserts.