The Association for Science Education

K2.2 Humans and Other Animals

Abstract

This article tries to emphasise the 'big picture' relating to human biology. It provides access to learning materials and to questions that can help elicit alternative conceptions held by learners on this topic. It covers the essential requirements for life and how organ systems work in the body; How different organ systems work and integrate in the body; Comparing humans to other animals and plants; Health and lifestyle choices linked to healthy body functions. The progression of pupils ideas from KS1-4 is outlined (Including MRSGREN) and suggestions are made for practical experiences to support learning.

This is one of 17articles whose main aim is to support the processes of teaching/learning between the science education tutor and the trainee science teachers with a focus on “teachers’ knowledge and understanding”. During a primary or secondary BEd, PGCE or GTP we hope that those learning to become science teachers will be able to challenge their own understanding of science and scientific concepts. Unit K0 specifically explores general issues relating to all the knowledge units - to the learning of science.

Standards: This unit specifically addresses Q14 but, appropriately used can contribute to and provide evidence of competence for many others of the standards especially Q4,6,7,8,18, 22 and 25.

Key words: Human, Organisms, Life processes

Contents

1.0 Introduction
2.0 The conceptual barriers to understanding
3.0 Progression in children's ideas
4.0 Giving Practical experiences
5.0 Useful References

1.0 Introduction

A few primary teachers will have completed some post 16 study or even have a degree in biology, and about half of the secondary science teachers will have a degree with some biology content. However, that means that a substantial number of trainee teachers of both primary and secondary phases will have an understanding of biology equivalent only to a grade C at GCSE. The aim of these five ‘biology’ units is to provide support for these trainees (via their tutors) so that they can either teach to GCSE level, or acquire an understanding at that level so they have the confidence to teach at primary school. The emphasis is on the conceptual changes needed by learners (tutors, teachers and their pupils) to come to an understanding of living things.

Humans and other animals

The National Curriculum once spelt out this human biology section in some detail, but only at KS4 Biology GCSE will this detail still dictate what should be taught.

Perhaps we get too caught up in this detail and sometimes don’t see the overall processes. Consider, for example, the materials (air and food) that we take into our bodies. In outline, we take food into the gut, break it up to get it into the blood, use most of it as a fuel (where it joins with the oxygen we breathe in, and comes out as carbon dioxide and water) and the rest for growth and repair, where it falls off as dead skin etc. In this way, although we are taking materials into our bodies every day we also get rid of them all again allowing us to remain roughly the same weight. With no formal teaching children may simply think food turns into energy and makes us grow, but once we start to tell children about enzymes, ATP, haemoglobin, and all the details of the digestive, circulation and respiratory systems, the big picture seems to disappear within the details.

2.0 The conceptual barriers to understanding

Download 2 is suitable to use with trainees to identify some misconceptions they may have and to set the scene to develop their confidence. (Additional elicitation questions in multiple choice format are in the PowerPoint in download 2.0a)

Potentially, there is a very large amount of detail concerned with the body and how it works and there is a great danger of overload with overuse of scientific terms. Also, detail can obscure the bigger picture about how the body works and how knowledge of that is very important to informing important lifestyle choices about how we look after our body or otherwise through patterns of diet, activity and intake of drugs. Important aspects to emphasise in this topic are:

  • The essential requirements for life and how different organ systems meet them
  • How the different organ systems work and how they integrate in the body
  • Comparing humans to other animals and plants
  • Health and lifestyle choices linked to healthy body functions

Children may have problems in making connections between the scientific ideas and how these relate to their own bodies with implications for how this informs lifestyle choices. Therefore, it is important to make direct meaningful connections with the ideas through practical activity wherever possible and to explore actively the effects of lifestyle choices on health.

Download K2.2_2.0a 'Personal Elicitation'

3.0 Progression in children's ideas

Children are exposed to ideas about how their bodies work from a very young age, and we need to take these naïve ideas into account as we try to help them develop a deeper understanding of human biology. We need always to keep the whole body in view, and not allow our study of individual systems to obscure this whole. The systems interact to provide the conditions for a healthy life, and it is this interaction which provides the meaning. So, even though we look at each system in turn we must always relate this to the other systems and the whole.

At KS1 the emphasis is to focus on children’s awareness of their whole body to develop understanding of the external parts through physical education activities in particular, which point out the parts and connect to some internal functions, particularly joints, muscles and movement, the senses, breathing, heart and pulse beat with connections to diet, exercise and the role of drugs as medicines. Comparisons with other animals show that we need the same essential factors for life, and this demonstrates that humans are also animals with close relations to other mammals. Children tend to relate closely to domestic or farm animals, though it is important to look at a range of other animals through, for example, ‘minibeast’ topics so that they see that all animals are related and have similar needs, even though they look very different. By emphasising such relationships the children may more readily show care for other living things, though this needs to be made explicit when handling living things.

Through KS2, 3 and 4 the functions of the body can be investigated systematically through looking at organ systems with increasing complexity at different ages and experience. The basic properties of life as shown by the mnemonic MRS GREN is a helpful way of understanding that all living things have the same essential requirements though their bodies have evolved differently in different environments under different natural selection pressures. In the following list the examples are human, but they apply (with more conceptual difficulty for children) to all other animals and plants just as well:

  • Movement (animals need to find shelter, food, a mate, avoid being eaten - achieved primarily through muscular and skeletal systems)
  • Respiration (energy is needed for life, achieved through energy transfer in cells when food is oxidised - supported through food and oxygen transport through the digestive, respiratory and circulatory systems)
  • Sensitivity to the environment (animals need to respond to stimuli to live in their environment - achieved through the senses and central nervous system, including the brain)
  • Growth (food is needed for growth and repair - materials are distributed through digestive and circulatory systems)
  • Reproduction (all living things need to produce copies of themselves - achieved through sex, fertilisation, growth, maturation and parental care in the case of humans)
  • Excretion (toxic wastes must be eliminated - done through the urinary system, breathing, and sweating)
  • Nutrition (food is needed for fuel, growth and repair - food is made available through the digestive system and transported through the circulatory system)

It is also very useful to link up these ideas to compare animals and plants to show how the various functions are met. This shows how all living things have particular strategies for similar functions. These close relationships between diverse living things are verified by over half our DNA being shared between other animals and plants and because of similar physiological functions, while we also share up to half of DNA with bacteria (ie half their DNA is found in us), indicating common physiological functions and common evolutionary ancestors in all living things. This confirms that all life belongs to ‘one family’ and we humans are in a real sense related to every other living thing on the planet:

Download 3.0a identifies the essential difference between animals and plants

With older children we still need to emphasise the same principles of connecting scientific concepts to understanding of our own bodies, with implications for lifestyle choices throughout. At an early stage it is best to avoid terminology overload, using functional terms, e.g. food tube, with the scientific term oesophagus coming later. As more complex understanding of similarities with other animals through comparisons of structure and function develops, as well as interrelationships with plants, the deep interrelationships of all living things becomes increasingly apparent. Direct experiences in nature through, for example, ecosystem studies and visits to natural sites are important in this process. This is an essential aspect of environmental education, where care and sensitivity to the environment can be fostered through experiencing awe and wonder in nature as well as demonstrating the interconnections and relationships between all living things through biological studies. At the higher levels, classification, genetics and evolution provide evidence for the ‘family of life’, as it has evolved over time, which supports an ethos of empathy and care for living things and the environment in general.

Download 3.0b addresses important features for teaching each organ system following the MRS GREN mnemonic

Keeping healthy
Taking care of our bodies by activities that promote health is the area where we exert the most direct influence on the equality of our lives. Choices of lifestyle can have a direct influence on health, hence the importance of understanding about healthy functioning of the body and the problems of ill-health. Scientific understanding of how our bodies work can inform these choices.

Download 3.0c addresses important features of keeping healthy, linking knowledge of the body to wider issues of lifestyle choices.

Download K2.2_3.0a 'the essential difference between animals and plants'
Download K2.2_3.0b ' important features for teaching each organ system following the MRS GREN mnemonic'
Download K2.2_3.0c 'keeping healthy'

4.0 Giving Practical experiences

Download 4.0a provides examples of activities appropriate for KS1 to 4 to address concepts relevant to the NC and to link these to children’s understanding of their own bodies and implications for lifestyle choices.

Download 4.0b is a power point presentation used for ITE students studying human body through the topic of health. The questions in the PowerPoint slides are taken from a set of over 100 available from www.escalate.ac.uk/1141. Percentages quoted in the slides are for a group of 100 trainee primary teachers on entry to ITE, having obtained a ‘C’ or better at GCSE, usually two or three years previously. The distribution of responses will give secondary trainees an insight into the misconceptions that survive a GCSE course, and all trainees some comfort that they are not alone with their own misconceptions about how genetics and evolution works. Many of the questions originated from the CDRom by Ross et al. (2005)

Download K2.2_4.0a 'Activities for School'
Download K2.2_4.0b 'Children's ideas about health'

5.0 Useful References

This unit used, as a major resource, the CDrom (Ross at al 2005) with support from the associated book (Littledyke, Lakin and Ross, 2000) and the course guide (Littledyke et al., 2006).

Section Developed by: Michael Littledyke, University of Gloucestershire

Published: 23 Aug 2006, Last Updated: 12 Sep 2008