Question

Match the numbered terms to the description that follows. Choose all appropriate terms. A prokaryote that obtains both energy and carbon as it decomposes dead organisms is a(n): 1. autotroph 2. heterotroph 3. phototroph 4. chemotroph

Answer 1

Answer:

Answer is option (2) and (4).

Prokaryotes that obtain both energy and carbon as they decomposes dead organisms - heterotroph and chemotroph.

Explanation:

(1) Autotrophs or Producers - Organisms that produce their own food and get the energy to make food from inorganic sources or sunlight. They are the base level of the energy pyramid of an ecosystem. The existence of all other organisms depends on autotrophs as they provide fuel for others. Examples of autotrophs are green algae, all plants, photosynthetic bacteria, etc.

(2) Heterotrophs or Consumers - Organisms that consume autotrophs or other heterotrophs since they cannot produce their own food. They absorb nutrition from other organic carbon sources such as plant or animal matter. The examples of heterotrophs are fungi, all animals, many protists and bacteria.

(3) Phototrophs - Organisms that capture photons from light and convert it to chemical energy to carry out different cellular processes.

• Photoautotrophs (holophytic organisms) are autotrophs that carry out photosynthesis in which carbon dioxide and water are converted into organic compounds (glucose) using energy from sunlight. Plants, algae, photosynthetic bacteria are examples.
• Photoheterotrophs depend on sunlight for their energy and produce ATP through photophosphorylation. Their source of carbon is organic compounds such as carbohydrates, fatty acids, etc obtained from the environment and do not rely on carbon dioxide. Examples include green non-sulfur bacteria, purple non-sulfur bacteria, heliobacteria, etc.

(4) Chemotrophs - Organisms that obtain energy by breaking down or oxidation of organic or inorganic molecules such as ammonia,  carbohydrates, molecular hydrogen, sulfur, hydrogen sulfide, ferrous iron, etc through chemosynthesis.

• Chemoautotrophs synthesize organic compounds from carbon dioxide using the energy derived from chemical reactions. Most of them are found in deep water environments that receive no sunlight. Cyanobacteria, sulfur-oxidizing bacteria, iron-oxidizing bacteria, nitrogen-fixing bacteria, etc are examples.
• Chemoheterotroph uses inorganic or organic energy sources as they can not synthesize their own organic compounds. Chemolithoheterotroph uses inorganic energy sources (sulfur, ferrous iron, etc) and chemoorganoheterotroph uses organic energy sources (carbohydrates, proteins, lipids, etc). Examples of chemoheterotrophs include most fungi and animals.