1: Unicellular and Multicellular Organisms Flashcards
How many cells in a unicellular organism?
- one
What do unicellular organisms carry out inside them?
- all the functions of life
Give two examples of unicellular organisms.
- Paramecium
2. Chlamydomonas
Where does a Paramecium live? How long is a Paramecium?
- lives in ponds
2. 0.05mm - 0.33mm long
Where does a Chlamydomonas live? How long is a Chlamydomonas?
- freshwater habitats
2. 0.002mm - 0.010mm
Draw a Paramecium. (see p2)
- cilia
- contractile vacuole
- plasma membrane
- nucleus
- cytoplasm
- food in vesicles
Draw a Chlamydomonas. (see p2)
In common with Paramecium:
- contractile vacuole
- plasma membrane
- nucleus
- cytoplasm
Different to Paramecium:
- flagellum
- eye spot
- cell wall
- chloroplast
We are going to compare similarities and differences between Paramecium and Chlamydomonas. What functions of life are we going to compare?
Differences:
- Nutrition
- Excretion
- Growth
- Response
Similarities:
- Metabolism
- Homeostasis
- Reproduction
Compare ‘Nutrition’ of Paramecium and Chlamydomonas.
- Paramecium feeds on smaller organisms by ingesting and digesting them in vesicles
- whereas Chlamydomonas produces its own food by photosynthesis using a chloroplast
Compare ‘Growth’ of Paramecium and Chlamydomonas.
- Paramecium increasing in size and dry mass by accumulating organic matter and minerals from its food
- whereas Chlamydomonas increases in size and dry mass due to photosynthesis and absorption of minerals
Compare ‘Response’ of Paramecium and Chlamydomonas.
- Paramecium reacts to stimuli, e.g. reverses its direction of movement when it touches a solid object
- whereas Chlamydomonas reacts to stimuli, e.g. senses where the brightest light is with its eyespot and swims towards it
Compare ‘Excretion’ of Paramecium and Chlamydomonas.
- Paramecium expels waste products of metabolism, e.g. CO2 from respiration diffuses out of the cell
- whereas Chlamydomonas expels waste products of metabolism, e.g. oxygen from photosynthesis diffuses out of the cell
Compare ‘Metabolism’ of Paramecium and Chlamydomonas.
- Both produce enzymes which catalyse many different chemical reactions in the cytoplasm
Compare ‘Homeostasis’ of Paramecium and Chlamydomonas.
- Both keep internal conditions within limits, e.g. expels excess water using contractile vacuoles
Compare ‘Reproduction’ of Paramecium and Chlamydomonas.
- Both reproduce asexually using mitosis or sexually using meiosis and gametes