Answer:
D.
Explanation:
i never heard lonosphere when i learned about the three layers of the atmosphere
Answer:
Central canal
Explanation:
running through the osteon
central canal or haversian canal,contains blood vessels,nerves and lymphatic vessels.
Answer:
D. Fossil record.
Explanation:
The fossil record evidences the evolutionary history of life on Earth by tracing the life forms that existed from earlier geological times and remained in the sedimentary rock. Different fossils were dated in the sedimentary rocks of all geological periods. The simplest forms of life were discovered in the oldest rocks, while more complex fossil organisms were found in the newest rocks. In consequence, the fossil record can support the evolutionary process as proposed by Charles Darwin, who indicated that the simplest forms of life evolved in more complex organisms.
Answer:
1. interactions
2. environment
3. sun
4. photosynthesis
5. chemical
6. producers
7. food
8. energy
9. organisms
10. herbivores
10. first
12. Heterotrophs
13. second
Explanation:
An ecosystem consists of a community of living organisms
interacting with each other and the environment. The source of energy that fuels most ecosystems is the sun. Plants use the Sun’s energy to produce food in a process called photosynthesis.
Organisms that use energy from the Sun or energy stored in chemical compounds to produce their own nutrients are called autotrophs. They are also called producers because most other organisms depend on autotrophs for food and energy. Heterotrophic organisms that can’t make their own food may obtain nutrients by eating other organisms. A heterotroph that feeds only on plants is called an herbivore. Herbivores are also called first order heterotrophs. Heterotrophs that feed on other herbivores are second order heterotrophs.