Explanation

Ichthyology is the study of fish.

Ichthyology وہ علم جس میں مچھلی کا بیان یا ذکر ہو

Additional information:

Agrostology: Study of grasses 

Agronomy: Study of soil management and crop production 

Odontology: Study of teeth 

Arthrology: Study of joints 

Nephrology: Study of kidneys

Hematology: Study of blood  

Dermatology:  Study of skin

Explanation

The vertical movement of air is called air current.

Temperature differences can cause air currents because warmer air is less dense than cooler air, causing the warmer air to appear 'lighter'.

Air currents can be caused by differences in temperature, pressure, or impurity concentration.

Explanation

Potassium is the chemical element 

symbol K 

atomic number 19

Electron configuration: 4s1

Electrons per shell: 2, 8, 8, 1

Explanation

Carbon-12 (12C) is the most abundant of the two stable isotopes of carbon (carbon-13 being the other), amounting to 98.93% of element carbon on Earth;

its abundance is due to the triple-alpha process by which it is created in stars.

Explanation

Genes are the smallest functional units of hereditary material found on chromosomes.

Genes are made up of DNA.

Explanation

• Water vascular system in echinoderms used for Respiration
• ***
• The Water Vascular system in echinoderms is also used for locomotion, food, and waste transportation.
• The water vascular system helps in respiration, as the gaseous exchange takes place on the thin wall of feet tubes.
• The system consists of a central ring canal and radial canals extending along each arm
  

Explanation

• Pneumatic Technology deals with the use of compressed air to transmit power, control machines.
• It perform various tasks, such as powering tools, actuators, and pneumatic conveyance systems.

Explanation

Apiculture is the science and practice of rearing honey bees for honey, beeswax, and other products.

It involves the management and maintenance of bee colonies.

As well as the harvesting and processing of honey and other bee products.

Explanation

Explanation

Population density is the number of people living in a unit area of the earth's surface.

It is generally expressed as per square km.

The average density of the population in the whole world is 51 persons per square km.