After a meal containing carbohydrates, the concentration of glucose in the blood rises.
.1
Explain how the body returns the blood glucose concentration to normal after the meal.
[3 marks]
.2
What is the cause of type 1 diabetes?
[1 mark]
5 marksFoundation
Spec and skills
Original practice question
Answer and supported method checks
A student estimated the number of daisies in a field 50 m long and 40 m wide. She placed a 0.25 m² quadrat at five random positions and counted the daisies in each.
Daisies in five quadrats: 4, 7, 0, 5, 9.
Quadrat
1
2
3
4
5
Number of daisies
4
7
0
5
9
.1
Calculate the mean number of daisies per quadrat.
[2 marks]
.2
Estimate the number of daisies in the whole field.
[3 marks]
5 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
A student measured his reaction time. His partner held a ruler with the 0 cm mark level with the top of the student's thumb, then dropped it without warning. The student caught it as quickly as possible, and the partner read the distance fallen.
Conversion table from distance fallen to reaction time: 10 cm, 0.143 s; 11 cm, 0.150 s; 12 cm, 0.156 s; 13 cm, 0.163 s; 14 cm, 0.169 s; 15 cm, 0.175 s.
Distance fallen (cm)
10
11
12
13
14
15
Reaction time (s)
0.143
0.150
0.156
0.163
0.169
0.175
.1
In five trials the ruler fell 15 cm, 12 cm, 14 cm, 11 cm and 13 cm.
Calculate the mean distance.
[2 marks]
.2
Use the conversion table to give the student's mean reaction time.
[1 mark]
.3
Give two variables the student should control to make his results valid.
[2 marks]
3 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
Evolution is a change in the inherited characteristics of a population over time through natural selection.
.1
Put the stages of natural selection in order, starting with the first.
[2 marks]
.2
Define the term species.
[1 mark]
3 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
In 1990, Carl Woese proposed a three-domain system of classification.
.1
What are the three domains?
[1 mark]
.2
Explain why scientists changed from Linnaeus's system to the three-domain system.