Paper 2-style practice paper: Homeostasis · Inheritance, variation and evolution · Ecology (Foundation) — question paper

Section A: Multiple-choice questions[10 marks]

Choose one answer for each question. Each question is worth 1 mark.

1. 1

   Homeostasis means keeping the conditions inside the body

   1. Aidentical to the outside world
   2. Bcompletely frozen
   3. Cchanging constantly with the weather
   4. Dsteady and balanced
   ( )
2. 2

   A reflex action is

   1. Aa decision made by the conscious brain
   2. Brapid and automatic
   3. Calways painful
   4. Dlearned from parents
   ( )
3. 3

   The central nervous system consists of

   1. Athe brain and spinal cord
   2. Bsensory neurons only
   3. Call the muscles
   4. Dthe skin and eyes
   ( )
4. 4

   Insulin lowers blood glucose by making the liver

   1. Arelease glucagon
   2. Bbreak down glycogen
   3. Cstore glucose as glycogen
   4. Dmake more blood
   ( )
5. 5

   Type 1 diabetes is treated with

   1. Adiet changes alone
   2. Binsulin injections
   3. Cpainkillers
   4. Dantibiotics
   ( )
6. 6

   The sex chromosomes of a human male are

   1. AXY
   2. BXX
   3. CYY
   4. DXO
   ( )
7. 7

   By natural selection, organisms with the best adaptations are more likely to

   1. Alive forever
   2. Bstop evolving
   3. Cbecome fossils
   4. Dsurvive and reproduce
   ( )
8. 8

   A food chain may collapse when one species disappears because

   1. Athe sun dims
   2. Ball food chains are identical
   3. Cthe remaining species depend on each other for food
   4. Dwater stops cycling
   ( )
9. 9

   Fossils preserved in rocks show us

   1. Afuture species
   2. Borganisms that lived long ago
   3. Cliving cells
   4. Dweather patterns
   ( )
10. 10

    In selective breeding, humans choose parent organisms with

    1. Athe wanted characteristics
    2. Bcompletely random genes
    3. Cthe shortest lives
    4. Dno variation
    ( )

Section B: Structured questions[90 marks]

Answer all questions in the spaces provided.

1. 11

   This question is about the nervous system and reaction time.

   1. (a)

      Put the parts of a reflex arc in order from the stimulus: motor neuron; receptor; relay neuron; sensory neuron; effector.

      [3]
   2. (b)

      Explain why reflex actions do not involve the conscious part of the brain.

      [2]
   3. (c)

      Describe how a student can measure reaction time by catching a falling ruler.

      [4]
   4. (d)

      The student then repeats the experiment after drinking coffee. Give two variables that must be controlled for the comparison to be fair.

      [3]
   5. (e)

      What is a synapse, and how does a signal cross one?

      [3]
2. 12

   This question is about hormones and blood glucose.

   1. (a)

      What is a hormone?

      [2]
   2. (b)

      Explain how the body brings blood glucose back to normal after a sugary meal, and after vigorous exercise.

      [3]
   3. (c)

      Compare the cause and treatment of type 1 and type 2 diabetes.

      [3]
   4. (d)

      A person has a mass of 70 kg and a height of 1.75 m. Calculate their body mass index (BMI), using BMI = mass ÷ height². Give your answer to 1 decimal place.

      [3]
   5. (e)

      Name the gland that releases FSH and LH, and state one role each of FSH, oestrogen and LH in the menstrual cycle.

      [4]
3. 13

   This question is about reproduction.

   1. (a)

      Give one difference between sexual and asexual reproduction.

      [2]
   2. (b)

      Name the male and female gametes, where each is made, and define fertilisation.

      [3]
   3. (c)

      Describe what happens to the uterus lining during one menstrual cycle if the egg is not fertilised.

      [4]
   4. (d)

      Name one hormonal method of contraception and one barrier method, and say how each works.

      [3]
   5. (e)

      Where is DNA found in a cell, and what is a gene?

      [3]
4. 14

   This question is about inheritance.

   1. (a)

      Define the terms allele and dominant.

      [2]
   2. (b)

      Two pea plants are both Bb for seed shape (B = round, dominant; b = wrinkled, recessive). Complete a Punnett square and state the ratio of round to wrinkled offspring.

      [4]
   3. (c)

      Explain why, in humans, each child has approximately a 50% chance of being male.

      [3]
   4. (d)

      Give one example of genetic variation and one example of environmental variation in humans.

      [3]
   5. (e)

      A person carries one recessive allele for a genetic condition but shows no symptoms. Explain why, and what this person is called.

      [3]
5. 15

   This question is about evolution and classification.

   1. (a)

      State what Charles Darwin proposed in his theory of evolution.

      [2]
   2. (b)

      Describe the steps of natural selection.

      [4]
   3. (c)

      State one similarity and one difference between natural selection and selective breeding.

      [3]
   4. (d)

      Describe two lines of evidence for evolution.

      [3]
   5. (e)

      What does the binomial name of a species show, and give one example.

      [3]
6. 16

   This question is about ecosystems.

   1. (a)

      Define the terms population and community.

      [2]
   2. (b)

      A student samples a 400 m² field with 0.5 m² quadrats and counts a mean of 8 snails per quadrat. Estimate the snail population of the field.

      [4]
   3. (c)

      Write a four-organism food chain for a grassland, and state what the arrows in a food chain represent.

      [3]
   4. (d)

      Name one abiotic factor and one biotic factor, and explain how each could reduce a population.

      [3]
   5. (e)

      Explain how one adaptation of a cactus helps it survive in the desert.

      [3]