Fluoride in toothpastes prevent tooth decay from progressing and can even reverse, or stop, early tooth decay. It works by promoting a chemical reaction in tooth enamel that draws in replacement minerals including calcium. Fluoride incorporates itself into enamel weakened by acid attack, making the tooth more resistant to future acid attacks.

Correct Option: B

Fluoride in toothpastes prevent tooth decay from progressing and can even reverse, or stop, early tooth decay. It works by promoting a chemical reaction in tooth enamel that draws in replacement minerals including calcium. Fluoride incorporates itself into enamel weakened by acid attack, making the tooth more resistant to future acid attacks.

The brain’s limbic system controls emotional expression through the hypothalamus, which has control over the body’s emotional responses systems. The hypothalamus is responsible for regulating hunger, thirst, response to pain, levels of pleasure, sexual satisfaction, anger and aggressive behavior, etc. It also regulates pulse, blood pressure, breathing, and arousal in response to emotional circumstances.

Correct Option: A

The brain’s limbic system controls emotional expression through the hypothalamus, which has control over the body’s emotional responses systems. The hypothalamus is responsible for regulating hunger, thirst, response to pain, levels of pleasure, sexual satisfaction, anger and aggressive behavior, etc. It also regulates pulse, blood pressure, breathing, and arousal in response to emotional circumstances.

The bark of cinchona tree yields quinine, a white crystalline alkaloid having antipyretic (fever-reducing), anti-malarial, analgesic (painkilling), and antiinflammatory properties. Quinine was the first effective Western treatment for malaria caused by Plasmodium falciparum.

Correct Option: B

The bark of cinchona tree yields quinine, a white crystalline alkaloid having antipyretic (fever-reducing), anti-malarial, analgesic (painkilling), and antiinflammatory properties. Quinine was the first effective Western treatment for malaria caused by Plasmodium falciparum.

An organism that transmits a disease agent from an infected to a non-infected animal or plant is known as vector. The major classes of vectors are:
Non-living vectors (food, water, soil, other materials)
Arthropod vectors (fleas, ticks, mosquitoes)
Vertebrate vectors (rats, mice, cats, dogs, birds)

Correct Option: C

An organism that transmits a disease agent from an infected to a non-infected animal or plant is known as vector. The major classes of vectors are:
Non-living vectors (food, water, soil, other materials)
Arthropod vectors (fleas, ticks, mosquitoes)
Vertebrate vectors (rats, mice, cats, dogs, birds)

The endocrine glands are widely distributed throughout the body. The pituitary gland, pineal gland and hypothalamus are located in the skull. The thyroid and parathyroid glands are in the neck, and the thymus gland is in the thoracic (chest) cavity. The thymus gland is only active until puberty. It helps the body protect itself against autoimmunity.

Correct Option: B

The endocrine glands are widely distributed throughout the body. The pituitary gland, pineal gland and hypothalamus are located in the skull. The thyroid and parathyroid glands are in the neck, and the thymus gland is in the thoracic (chest) cavity. The thymus gland is only active until puberty. It helps the body protect itself against autoimmunity.