B4.2 Ecological-Niches - 2024

Obligate anaerobes

• Cannot survive in the absence of oxygen. They must live in environments where oxygen is available, and carry out aerobic respiration.

• Cannot survive in the presence of oxygen, and must live in oxygen-free environments such as waterlogged soil. They carry out anaerobic respiration.

• survive in the presence or absence of oxygen. These organisms carry out anaerobic respiration in the absence of oxygen, and aerobic respiration in the presence of oxygen.

• produce organic compounds in cells using light energy.

Photosynthesis

• is the production od energy using energy from other organisms

• consume energy by breaking down dead organisms externally and internalising the nutrients

• uses different inorganic compounds such as ammonia, nitrites and sulfur compounds

• is the production of organic compounds in cells using light energy.

Facultative anaerobes:

• Cannot survive in the presence of oxygen, and must live in oxygen-free environments such as waterlogged soil. They carry out anaerobic respiration.

• Can survive in the presence or absence of oxygen. These organisms carry out anaerobic respiration in the absence of oxygen, and aerobic respiration in the presence of oxygen.

• Cannot survive in the absence of oxygen. They must live in environments where oxygen is available, and carry out aerobic respiration.

• produce organic compounds in cells using light energy

Obligate aerobes

• Cannot survive in the absence of oxygen. They must live in environments where oxygen is available, and carry out aerobic respiration.

• Cannot survive in the presence of oxygen, and must live in oxygen-free environments such as waterlogged soil. They carry out anaerobic respiration.

• : Can survive in the presence or absence of oxygen. These organisms carry out anaerobic respiration in the absence of oxygen, and aerobic respiration in the presence of oxygen

• food is ingested, digested internally, absorbed and assimilated.

HOLOZOIC nutrition - is a form of heterotrophic nutrition where an organism:

• Internally digests food

• produces food using light energy

• Ingests food

• Absorbs and assimilates the nutrients from digested food.

Obligate mixotrophs

• can switch between the two modes of nutrition based on available resources. They can obtain all of their required nutrients using either autotrophic or heterotrophic modes of nutrition.

• Cannot survive in the absence of oxygen. They must live in environments where oxygen is available, and carry out aerobic respiration.

• require both autotrophic and heterotrophic modes of nutrition to survive.

• Cannot survive in the presence of oxygen, and must live in oxygen-free environments such as waterlogged soil. They carry out anaerobic respiration.

Facultative mixotrophs

• cannot survive in the presence of oxygen, and must live in oxygen-free environments such as waterlogged soil. They carry out anaerobic respiration.

• can survive in the presence or absence of oxygen. Facultative anaerobes carry out anaerobic respiration in the absence of oxygen, and aerobic respiration in the presence of oxygen.

• can switch between the two modes of nutrition based on available resources. They can obtain all of their required nutrients using either autotrophic or heterotrophic modes of nutrition.

• cannot survive in the absence of oxygen. They must live in environments where oxygen is available, and carry out aerobic respiration.

Saprotrophs

• are autotrophs that obtain nutrients by external digestion of food.

• are heterotrophs that obtain nutrients by internal digestion of food.

• are autotrophs that obtain nutrients by internal digestion of food.

• are heterotrophs that obtain nutrients by external digestion of food.

ARCHAEA

• are prokaryotes that are found in a wide variety of environments, and they are metabolically diverse.

• are eukaryotes that are found in a wide variety of environments, and they are metabolically diverse.

• are prokaryotes that are found in a small number of environments, and they are metabolically diverse.

• are prokaryotes that are found in a wide variety of environments, and they are metabolically the same

Archaea Phototrophs

• oxidize inorganic compounds to produce ATP.  Different species of archaea use different inorganic compounds such as ammonia, nitrites and sulfur compounds.

• oxidize organic compounds, such as sugars and fatty acids, to produce ATP.

• use light energy to produce ATP. This is a different process than photosynthesis and no oxygen is produced.

• carry out anaerobic respiration in the absence of oxygen, and aerobic respiration in the presence of oxygen.