Explanation

There are no vaccines to prevent or treat HIV, but people with HIV can benefit from vaccines against other diseases.

Explanation

Quantum numbers describe values of conserved quantities in the dynamics of a quantum system

Explanation

Explanation

The troposphere is the lowest layer of Earth's atmosphere. 

The Layers of atmosphere are: the troposphere, stratosphere, mesosphere and thermosphere.

Explanation

A covalent bond is the force of attraction that holds together two atoms that share a pair of valence electrons. The shared electrons are attracted to the nuclei of both atoms. This forms a molecule consisting of two or more atoms.

Explanation

 heterozygous sickle cell anemia gives protection against malaria

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Heterozygotes are therefore more resistant to the debilitating effects of malaria than the normal homozygotes.

sickle cells are also resistant to malaria.

Heterozygotes are resistant to malaria

because of their recessive allele, but they lack sickle cell disease because of their dominant allele

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Explanation

The secretions of these accessory glands in urethra of male rabbit neutralizes the urinary residue and vaginal acidity

Explanation

Lead is a chemical element.

Symbol Pb  and atomic number 82.

It is a heavy metal that is denser than most common materials.

Explanation

•  A, D, E, and K are fat-soluble vitamins.
• Fat-soluble vitamins are absorbed by the body along with dietary fats.
• They are present in foods that contain fats.
• The body stores these vitamins in the liver and fat tissue when they are not in use. 
• Megadoses of fat-soluble vitamins can be toxic.

Explanation

Photosynthesis takes place in the chloroplast.

The chlorophyll present in the chloroplast traps the light from the sun and carries out the process.