Explanation

In the membranous skeleton, the perineurium sheath surrounds the central nervous system. 

The perineurium is a protective layer of connective tissue that encases nerve fibers.

It providing support and shielding them from external damage.

Explanation

Gigantic clouds of dust and gas in space are called nebulae

Primarily hydrogen and helium, plus dust (silicates, carbon, ice). 

Occupying the space between stars and acting as a nursery for new stars

Explanation

Vision is the least developed sense at birth, as the womb is a dark place and there is little opportunity for development.

Hearing: Develops relatively well during pregnancy, allowing babies to hear sounds from around the 20th week. 

Touch: Also develops fairly well in utero, providing comfort and a sense of security. 

Smell and Taste: These senses are closely linked and are important for newborns to recognize their mother's breastmilk and establish bonding. 

Explanation

Minerals include calcium and iron among many others and are found in:

meat.

cereals.

fish.

milk and dairy foods.

fruit and vegetables

Explanation

A pandemic is an epidemic of an infectious disease that has spread across a large region,

for instance multiple continents ,

affecting a substantial number of individuals.

Explanation

Hypothermia is caused by exposure to cold temperatures for a long time.

It can also occur after prolonged immersion in cold water. 

Causes 

Cold temperatures: Exposure to temperatures below 10°C for a long time

Cold water: Prolonged immersion in water below 20°C

Wet clothing: Wearing wet clothing in cold or windy weather

Heavy exertion: Exerting yourself while in cold weather

Dehydration: Not drinking enough fluids in cold weather

Undereating: Not eating enough in cold weather

Explanation

The annual number of live births per 1,000 people is called the Crude Birth rate

ہر ایک ہزار افراد کی سالانہ پیدائش کی شرح کو خام پیدائش کی شرح کہا جاتا ہے۔

the annual number of deaths per 1,000 people is called the Crude death rate

ہر ایک ہزار افراد کی سالانہ اموات کو خام اموات کی شرح کہا جاتا ہے۔

Explanation

 Each person has between 5,000 and 10,000 taste buds, most of which are located in papillae

. Taste buds are also scattered across the roof of the mouth and the back of the throat.

Explanation

Biodiversity is the variability among living organisms from all sources,

Including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part;

This includes diversity within species, between species, and of ecosystems.