Explanation

Demography is the statistical study of human populations.

Demography examines the size, structure, and movements of populations over space and time. 

Explanation

A solar eclipse can only take place during the phase of the new moon

when the moon passes directly between the sun and Earth and its shadows fall upon Earth's surface.

Explanation

Thus, the First law of thermodynamics furnishes the relationship between:

• heat
• work
• the internal energy of the system

Explanation

• Membranes present around the embryo are Chorion
• ***
• Chorion is also called Serosa
• in reptiles, birds, and mammals, the outermost membrane around the embryo.
• It develops from an outer fold on the surface of the yolk sac.
• **
• The fetal membranes or extraembryonic membranes, are membranes associated with the developing fetus.
• The two chorioamniotic membranes are the amnion and the chorion
  

Explanation

Entomology is the study of insects and their relationship to humans, the environment, and other organisms.

while

Zoology is the study of all animals.

Biology is a natural science concerned with the study of life and living organisms.

Etymology investigates and documents the lives.

Explanation

A hutch is a type of cage used typically for housing domestic rabbits.

Other small animals can also be housed in hutches such as guinea pigs, ferrets,

Explanation

Philology is the study of languages in written historical sources.

It includes the analysis of literary texts, history, and the development of languages.

Explanation

Water has maximum density at 4°C.

When Water is in its Solid form (Ice) below 0°C.

Explanation

To find the hidden secrets under the water,

the ships and submarines use the Sonar system.

Sonar uses sound waves to 'see' in the water.

There are two types of sonar—active and passive.

Explanation

The correct pathway of a nerve impulse is Receptors → CNS → Effectors. 

Receptors:

• These are specialized cells that detect stimuli (changes in the environment) like light, temperature, or pressure.
• They convert these stimuli into electrical signals.

CNS (Central Nervous System):

• This includes the brain and spinal cord.
• The sensory neurons transmit the electrical signals from the receptors to the CNS.
• In the CNS, the information is processed and a decision is made about how to respond.

Effectors:

• These are the organs or muscles that carry out the response.
• The CNS sends motor neurons to the effectors, which then trigger the muscle to contract or gland to secrete a substance.