Is It Alive Practical Part 1

For this experiment, we were given 5 substances (A, B, C, D, E) and were supposed to determine if they were living things.

PART 1A

Criteria of living things tested: Requires water & nutrition (food)

Procedure:

• Label the tube A, B, C, D and E.

• Pour substance A in tube A and repeat for all the substances.

• Add 3ml of water to each of the tube. Mix well.

• Start your stop watch.

• Observe. Write your observations in the journal. Use the suggested table format (Table 1) provided below.

• After 10mins, record the observation again.

 

Table 1

Substance	Evidence of Life (Inference)	Observations		Is it Alive? Yes/No
		0 minutes	10 minutes
A	None	Not moving, floating,  water slightly murky. Odourless. Brownish-yellowish colour	Unchanged	No
B	Bubbles appeared- respiration	Milky, creamy white, sticky, smells bad.	Slightly mushy and bubbles appeared at the bottom, liquid level rose	Yes
C	They grew and took in water	Clear transparent spheres	They expanded, water level decreased till none left	Yes
D	None	Odourless, most sink to the bottom, some float. Colours range from red to deep purple	Same	No
E	Took in water	Brown in colour, Floating to the top. Feels grainy	Water level decreased	Yes

PART 1B

Procedure: Repeat earlier steps with glucose instead of water.

Table 2

Substance	Evidence of Life (Inference)	Changes Observed after 10 minutes
A	Not alive	Unchanged
B	Bubbles appeared - respiration - alive	Sticky, mushy, many bubbles found at the top
C	Grew - alive	Stuck together, grew larger and rougher
D	Not alive	Liquid murkier
E	Not alive	Floated to the surface

(done 5/7/13)