Chapter 11 Adaptations For Nutrition

Question 1

Define autotroph

Answer 1

An organism that synthesises its own complex organic molecules from simpler molecules using light or chemical energy.

Question 2

What is photoautotrophic?

Answer 2

Organisms that use light as the energy source for photosynthesis.

Question 3

What is chemoautotrophic?

Answer 3

Organisms that use chemical energy for chemosynthesis

Question 4

Define heterotroph

Answer 4

An organism that obtains complex organic molecules from o5er organisms.

Question 5

Define saprotroph

Answer 5

An organism that derives energy from the extracellular digestion of dead or decaying material.

Question 6

Define parasite

Answer 6

An organism that obtains nutrients from another living organism, it’s host, to which it causes harm

Question 7

What is holozoic nutrition?

Answer 7

Mode of nutrition in which organisms ingest, digest, absorb and egest food.

Question 8

Explain the holozoic nutrition in amoeba?

Answer 8

Amoeba obtain all the nutrients that they need by diffusion, facilitated diffusion or active transport across its cell membrane. They take in (ingest) larger molecules and microbes by endocytosis into food vacuoles which fuse with lysosomes. The contents are broken down (digested) by lysosomal enzymes. The products are absorbed into the cytoplasm and indigestible remains are egested by exocytosis.

Question 9

What are the 4 functions of the human gut?

Answer 9

Ingestion
Digestion
Absorption
Egestion

Question 10

What is the structure of the gut wall?

Answer 10

The outermost layer is the serosa (connective tissue with protective function). Muscle layer, circular and longitudinal muscle that contract for peristalsis. The submucosa, contains blood vessels which absorb products of digestion. The mucosa, the innermost layer that secretes mucus lubricating food and protecting the mucosa