General Science Mixed Quiz: Set 162

Papaya bears unisexual flowers: a flower has either stamens or a pistil, and male and female flowers usually grow on separate plants.

Nephology is the study of clouds, their formation, classification into types such as cirrus, cumulus and stratus, and their part in rainfall, and it is a branch of meteorology, the science of the atmosphere and the weather.

In uniform circular motion the body covers equal arcs in equal times, so its speed, a scalar, does not change; its kinetic energy and its angular velocity are constant too.

With no external force on the system, its centre of mass cannot start moving. The throw is an internal force: X pushes the tool forward and the tool pushes X backward with an equal and opposite force (Newton's third law).

In this stage the condensed chromosomes, each consisting of two sister chromatids, are moved by the spindle fibres until their centromeres lie in one plane across the middle of the cell, known as the metaphase plate or equatorial plate.

The Sweet Revolution is the term used for the drive to raise honey production and beekeeping in India, supported by the National Beekeeping and Honey Mission.

The egg is fertilised to form the zygote, the zygote grows into the embryo, and the ovule carrying the embryo becomes the seed.

A beam seen from the side is visible only because tiny particles send some of its light sideways. Light travelling in a straight line cannot enter our eyes unless something redirects it towards us.

The centrifugal force has the same magnitude as the centripetal force, which for a body moving in a circle is the mass multiplied by the square of the angular velocity multiplied by the radius.

Levers are grouped by where the fulcrum, the load and the effort sit. In a second class lever the load lies between the fulcrum and the effort.

Once the chromosomes are aligned on the metaphase plate and every kinetochore is attached to a spindle fibre, the centromere holding the two sister chromatids together splits.

Newton's second law gives force = mass × acceleration. Mass has the dimension [M], and acceleration is velocity divided by time, that is [L T⁻¹] ÷ [T] = [L T⁻²].

In an apple, the fleshy part we eat develops from the thalamus, the swollen tip of the flower stalk, and not from the ovary, which is why it is called a false fruit.

Protein synthesis begins with transcription, in which the message of a gene is copied from DNA into messenger RNA, so the first event is the making of an mRNA copy.

Distance is the length of the actual path and displacement is the straight line from the start to the finish, so on a curved path the two can never be equal: the arc of a circle is always longer than the chord joining its ends.

A lactometer is a floating instrument that measures the relative density of milk. Pure milk has a density slightly greater than that of water, so adding water lowers the reading and the float sinks deeper, which is how dilution is detected.

An animal cell divides its cytoplasm by a cleavage furrow, in which the plasma membrane is pulled inward around the middle until the cell is pinched into two.

The nucellus is the mass of tissue inside the ovule whose cells carry stored food, and the embryo sac develops within it.

The angle of repose is the angle to which an inclined plane must be tilted before a body resting on it just begins to slide.

Meiosis begins with a single round of DNA replication and is then followed by two successive nuclear divisions. Meiosis I is the reduction division, in which homologous chromosomes separate and the two cells formed already carry half the parental chromosome number.