Core Practicals

Question 1

investigate the population size of an organism in two different areas using quadrats

Answer 1

place 2 tape measures perpendicular to each other to create a grid. Use a random number generator to generate coordinates and place bottom left corner of the quadrant on it. Count the number of plants. Estimate dpop size = total area/ area of one quadrant x mean number of plants per quadrat.

Question 2

investigating the conditions needed for seed germination

Answer 2

Push cotton wool to the bottom of each boiling tube. Add a small amount of water to moisten. Add 10 cress seeds to each tube. Place a tube in a dark bench with no water, lab bench with water, dark cuboid with water, dark fridge with water. They need warmth moisture and oxygen. Count how many germinate in each

Question 3

investigating the energy content in a food sample

Answer 3

record mass of sample. Measure 20cm^3 cold tap water into a boiling tube. Clamp above a heatproof mat. Place a thermometer in the water. Set up a Bunsen burner away from the heatproof mat. Hold the burning food under neath the water from the same distance and the room temperature. Gently stir. Record ht e highest temp reached.