Biology MCQs

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Alzheimer’s disease is a progressive neurologic disease of the brain leading to the irreversible loss of neurons and the loss of intellectual abilities, including memory and reasoning. These with time become severe enough to impede social or occupational functioning. Alzheimer’s disease is also known as simply Senile Dementia.

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Females have single uterus. Also known as womb, it is a major female hormone-responsive reproductive sex organ of humans and most other mammals. It is within the uterus that the fetus develops during gestation.

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Tuberculosis caused by Mycobacterium tuberculie which primarily affects lungs although can affect other body too while early 19th century was called ‘white plague’ because of the large number of the people dying of its infection.

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The leaves arise in the regions of the plant known as the plant nodes and are therefore the point of attachment of the leaves. The region of the plant between two nodes is known as the internode. The angle between the upper surface of the leaf and the stem from which it arises is known as the axil.

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Motor skills are needed to control the movements of the different muscles in the human body. The frontal lobe plays a large role in voluntary movement. It houses the primary motor cortex which regulates activities like walking. The frontal lobes are also involved in problem solving, spontaneity, memory, language, initiation, judgement, impulse control, etc.

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Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle. The word “prokaryotic” means “before nucleus.” Prokaryotes include two groups: bacteria and another group called archaea. In contrast, eukaryotic cells have a “true” nucleus containing their DNA.

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A wisdom tooth, in humans, is any of the usual four third molars. Wisdom teeth usually appear between the ages of 16 and 25. They are generally thought to be called wisdom teeth because they appear so late – much later than the other teeth, at an age where people are presumably “wiser” than as a child, when the other teeth erupt.

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Acidity and alkalinity are expressed on the pH scale, which ranges from 0 (strongly acidic) to 14 (strongly basic or alkaline). A pH of 7.0, in the middle of this scale, is neutral. Blood is normally slightly basic, with a normal pH range of 7.35 to 7.45.

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When a DNA solution is heated enough, the double-stranded DNA unwinds, and the Hydrogen bonds that hold the two strands together weaken and finally break. The process of breaking a double-stranded DNA into single strands is known as DNA denaturation, or DNA melting. The hyper-chromicity of DNA occurs when the DNA duplex is denatured.

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Cell division is the process by which cells produce new cells. In animals some tissues must be repaired often such as the lining of gut, white blood cells, skin cells with a short lifespan. Other cells do not divide at all after birth are neurons.