Allergies are caused by environmental factors known as allergens like dust, pollen, ceramics etc.
Cystic fibrosis is an autosomal recessive genetic disorder.
Common cold is caused by viruses i.e. pathogen.
Skin cancer is caused due to genetic factors like mutations & also, due to exposure to UV radiation.
Malaria is caused by a pathogen named as Plasmodium. Female Anopheles mosquito is the carrier of plasmodium. The plasmodium completes half of its life cycle in Female Anopheles mosquito & its rest of the life cycle is completed in human body.
External Respiration takes place in the Trachea. When oxygen and co2 "switch" its where they connect and making this external respiration!
I hope this helps you!
Answer:
B: Freshwater biomes are a vital source of drinking water.
Explanation:
It's not A because oceans are part of marine biomes, and oceans contain 97% of the Earth's water and covers 71% of the Earth's surface.
It's not C because marine biomes supplies more oxygen than freshwater biomes. Marine algae supply much of the world's oxygen supply, and they take in a huge amount of atmospheric carbon dioxide.
It's not D because freshwater biomes include streams, rivers, ponds, and lakes. Aquatic biomes include oceans, coral reefs, and estuaries.
It's B because freshwater biomes are very important to our survival because they supply people with more than half of their drinking water.