2.4 Nutrition in unicellular organisms

Question 1

give an example of a unicellular organism

Answer 1

amoeba

Question 2

is amoeba autotrophic or heterotrophic

Answer 2

heterotrophic

Question 3

what type of heterotrophic is an amoeba

Answer 3

holozoic

Question 4

does amoeba digest intracellularly or extracellularly

Answer 4

intracellular digestion
- digests food within itself

Question 5

how does amoeba digest things

Answer 5

• phagocytosis (engulf food by engulfing)
• pinocytosis (budding of cell membrane to form vesicles)
• lysosomes containing digestive enzymes fuse with food vacuole
• food digested, then soluble molecules are absorbed into cytoplasm
• food which is not absorbed is passed out via exocytosis. -vesicles fuse with plasma membrane