Answer:
When respiration occurs without oxygen, lactic acid is produced. Answer is A.
Answer:
Circulatory System
Explanation:
Capilaries are tubes that transport blood and provide nutrition through diffusion in tissues. Transporting blood is a function of the circulatory system.
Answer:
8.7 million
Explanation:
About 8.7 million (give or take 1.3 million) is the new, estimated total number of species on Earth -- the most precise calculation ever offered -- with 6.5 million species on land and 2.2 million in oceans.
