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Bilogy 1 Living Things

Biology: 1. Living Things

Please remember to photocopy 4 pages onto one sheet by going A3→A4 and using back to back on the photocopier


OB38 Understand how to use a simple key to identify plants and animals, including vertebrates and invertebrates


OB39 Investigate the variety of living things by direct observation of animals and plants in their environment; classify living organisms as plants or animals, and animals as vertebrates or invertebrates


OB40 Identify the basic life processes and characteristics common to all living organisms: nutrition, respiration, excretion, growth, reproduction, movement and response


OB41 Recall that living things are composed of cells, tissues, organs and systems, and understand that growth results from cell division



Biology is the study of living things (called organisms)

            Student Notes




The living things which we are most familiar with are plants and animals.




Make their own food

Do not make their own food

Do not move from place to place

Move from place to place

Have cell walls

Do not have cell walls



Animals can then be sorted into two groups:

  1. Vertebrates = Animals that have a backbone. (Mammal, fish, bird, reptile, amphibian).
  2. Invertebrates = Animals that do not have a backbone. (Spiders, worms, jellyfish, anemones, etc).



Biology Keys

A key in Biology is a set of instructions which help us to identify or classify an organism.

The key on the right helps us to identify classify different types of vertebrates.

Can you identify where humans fit into this map?


Example 2: Identify the animals  below using the key on the next page

1. _______________5. _____________


2. ______________ 6.  _____________


3. _____________ 7.  _______________

4. ____________ 8.  _______________


9. ________________




      Does it have a backbone?





Does it have wings?




Does it have legs?

Does it have a shell?




Does it live in the water all the time?


Does it live in the water some of the time?




Does it have scaly skin?






Does it have fur?



How many legs has it got?








Does it have a jelly like body?

Does it have spiny skin?

Does it have segmented body?


(e.g. ringed worms)



(e.g snails)



Coelenterate (e.g. jellyfish)




(e.g. starfish)






Basic life processes and characteristics common to all living organisms
All living things have 7 life processes or characteristics in common.
These are (think ‘Mrs Gren’):

  1. Movement
    All living things can move. Animals can walk, fly etc, plants move their parts.
  2. Respiration
    Respiration is the release of energy from food. Aerobic respiration uses oxygen to obtain energy from food.
  3. Sensitivity
    Sensitivity is the ability to detect and respond to stimuli or changes in the environment.


  1. Growth
    All living things can grow/increase in size.
    This happens through cell division where cells have the ability to make copies of themselves.
  2. Reproduction
    Reproduction is the formation of new individuals.
    Organisms must be able to reproduce themselves or their species will become extinct.
  3. Excretion
    Excretion is getting rid of waste products from chemical reactions in the body e.g. carbon dioxide.
  4. Nutrition
    Nutrition is the way organisms obtain and use food. Food is needed as a source of materials and energy.






Cells, Tissues, Organs and Systems




All organisms are composed of cells which form tissues which form organs which in turn form systems.






Cells                →        Tissues                        →        Organs                        →        Systems




Cells are the main building blocks of life, e.g. blood cells and skin cells.

(We will look at them in detail in the next chapter).



A tissue is made up of a group of similar cells which carry out the same function, e.g. skin tissue and  muscle tissue.



An organ is made up of different types of tissue working together, e.g. the heart and the lung.



A system is formed by a group of organs working together, e.g.  the reproductive system and the digestive system.






The bits they don’t want you to know about

“It’s extraordinary that so much time is spent educating people about birth and sex, but so little about this equally profound thing [death] that happens to everyone.

Paul Murray (Irish Hospice Foundation)


Nearly 30,000 people die every year in Ireland. So perhaps we should spend a little more time on this issue (death).


Imagine you’re eighty years old. You are sick and have the option of living for another year if you remain in hospital or living for six months more if you live at home. Which would you choose and why?




Have you seen the film ‘The Bucket-List’?
Have you a list of things you would like to before you die?
Have you written them down – what are they (how many are secret)?


How many people die as a result of road accidents in Ireland every year?


How many people die by suicide every year?



Exam Questions

1.[2012 OL]

All living organisms have common characteristics e.g. respiration.

Give two other characteristics of living organisms.


  1. [2011][2009 OL][2007 OL][2012 OL]

Name one invertebrate animal and one vertebrate animal


  1. [2009 OL]

36 – 370 C

86 – 870 C

  1. Choose the correct temperature range of human body temperature from the list on the right.
  2. Give one reason for a change in body temperature.



  1. [2008 OL]


Key feature of organism


Four pairs of legs


Segmented body, no legs


Three pairs of legs


Eight to ten pairs of legs

The table shows a simple key used to identify some common organisms found in a habitat.

In the case of any two of the organisms shown on the right, write the letter corresponding to a key feature given in the table above beside the organism which that best describes.



  1. [2008 OL]




Digestive system



  1. Write the letter T opposite the name of a body tissue in the table on the right.
  2. Write the letter O beside the name of a body organ in the table on the right.


Exam Solutions


  1. Nutrition (feeding)// excretion// reproduction// growth// movement//response (sensitivity)
  2. Invertebrate: slug/ snail/ mussel/ bee/ wasp/ fly/ spider/ starfish/ prawn…

Vertebrate: fish/ lizard/ snake/ dog/ cat/ bird/ frog/ newt/ toad/ bat/ whale…

  1. 36 – 370 C
  2. Illness / stress / pain / exercise
  1. A: Spider
  2. C: Wasp
  3. D: Caterpillar
  1. T: Muscle 
  2. O: Heart







Other Test Questions

  1. List six characteristics of living things.


  1. What is an organ made up of?


  1. Define (i) sensitivity, (ii) reproduction, (iii) respiration and (iv) excretion.


  1. Explain the term tissue.


  1. What process do cells undergo to allow growth in organisms?


  1. When discussing ‘Living Things’, why are so few people prepared to discuss ‘Death’?
    Is death natural or unnatural?
    How do most animals in ‘nature’ die?
    If another animal attacked a koala bear who would like to see win the fight? Why?
    Every single one of us will die someday - have you ever discussed your death with anyone?
    Has anyone else ever discussed their death with you?


7.First life hydrothermal vents pansperpia mars us egocentricity embryos

8.Is a virus alive is a fire, is a cell, is a sperm cell?

  1. Is the sperm or egg alive

10. IVF with an embryo frozen for almost 20 years has resulted in a healthy birth, beating the previous recond by seven years


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