3 7A Signs of life - Life on Mars? TEACHER’S NOTESTo be used as a starting point for classroom discussion
4 A simple way of sorting everything on our planet 7A Signs of life - Life on Mars?Serious efforts to discover life on other planets have been going on for many years.If extra-terrestrial beings really were discovered how would scientists decide if they were alive?A simple way of sorting everything on our planetis to divide it into 2 groups– living things and non-living things.But can you tell the difference?
6 There are seven essential life processes. 7A Signs of life – The meaning of lifeThere are seven essential life processes.To remember these processes meetour little blue woman MS. R. NERG…What do all the letters in her name stand for?
7 Living things notice and react to changes in 7A Signs of life - The meaning of lifeM = MOVEMENTLiving things are able to move about. Animals move from place to place. Plants move by responding to light.S = SENSITIVITYLiving things notice and react to changes intheir surroundings. They can respond to light, heat, sound, taste, sight or touch.R = RESPIRATIONLiving things need energy to carry out thefunctions that keep them alive. Respiration is the process by which food is turned into energy.
8 Living things have to get rid of unwanted waste products. 7A Signs of life - The meaning of lifeN = NUTRITIONLiving things need to take in food so that respiration can occur. Nutrients in food help to build, maintain and repair the organism.E = EXCRETIONLiving things have to get rid of unwanted waste products.R = REPRODUCTIONLiving things produce offspring. Reproduction continues the survival of each species.G = GROWTHLiving things grow, increasing in size and complexity.
9 All living things carry out the seven essential life processes. 7A Signs of life - The meaning of lifeAll living things carry out the seven essential life processes.MSRNEG= Movement= Sensitivity= Respiration= Nutrition= Excretion= Reproduction= GrowthBut what are living things made of?
10 Building blocks of life 7A CellsBuilding blocks of life
11 Living things are made up of tiny building blocks called cells. 7A Building blocks of life - Cell fact fileLiving things are made up of tiny building blocks called cells.Each cell breathes, takes in food, gets rid of wastes, grows, reproduces and dies.A living thing can be just one cell ormillions of cells.Big living things don’t have bigger cellsthey just have more cells.
12 Think about the size of your little toe. 7A Building blocks of life - Cell fact fileAmazingly, the human body has more than 10,000,000,000,000 (that’s 10 million million) cells!Think about the size of your little toe.It has about 2 or 3 thousand million cells!That’s a lot of cells to make one toe,so cells must be very, very, very small.How do we know about cells if they are so small?
13 Cells could not have been discovered 7A Building blocks of life - Cell-ebrate the MicroscopeCells could not have been discoveredwithout the invention of the microscope.“micro-” means” small”,“-scope” means “looking at”.A microscope allows us to look at very small things by making them seem bigger. It magnifies tiny details and makes them visible to the human eye.
14 Cell-ebrate the microscope! 7A Building blocks of life - Cell-ebrate the MicroscopeCell-ebrate the microscope!
15 This is a typical animal cell. 7A Building blocks of life - Cell-ebrate the microscopeEvery living thing – from an elephant to an ant, from a tree to a daisy, from your left toe to right earlobe – is made of cells.Microscopes allow us to magnify cells revealing their shape and structure.This is a typical animal cell.Do animal and plant cells look the same?
16 7A Building blocks of life - Typical animal cell TEACHER’S NOTESClick on the forward button to reveal a diagram of a typical animal cell.Move the cursor over the labels beneath the cell diagram to reveal descriptions of the parts of the cell.
17 7A Building blocks of life - Typical plant cell TEACHER’S NOTESClick on the forward button to reveal a diagram of a typical plant cell.Move the cursor over the labels beneath the cell diagram to reveal descriptions of the parts of the cell.
18 Compare a typical animal cell and a typical plant cell. 7A Building blocks of life - Typical cellsCompare a typical animal cell and a typical plant cell.TEACHER’S NOTES- get students to draw up table listing all possible parts of cell and tick/cross in column for animal cell and plant cell.- lead into consideration of why do plant cells and animal cells have different structures?Which parts of a plant cell are the same as an animal cell?Which parts of a plant cell are not found in an animal cell?
19 Building living things 7A CellsBuilding living things
20 What could you do if you were one cell? 7A Building living things - Cells working togetherWhat could you do if you were one cell?Not much! You’d be a blob, with lots of pieces floating around inside of you!Keeping you alive is a big job. So your body is made of millions of cells that have to be very organised.Your body has organs that each carry out specific jobs to keep you alive.How many organs can you name?
21 Identify the organs labelled in the diagram. brain eye ear tongue 7A Building living things - Cells, tissues and organsIdentify the organs labelled in the diagram.braineyeeartongueheartskinlungstomachintestinesmuscle
22 Similar cells that do the same job work together to make tissue. 7A Building living things - Cells, tissues and organsSimilar cells that do the same job work together to make tissue. Muscle cells make muscle tissue.What type of cells are nerve tissue and blood tissue made from?muscle tissueCells are the building blocks of all living organisms.Different cells do different jobs.How do the millions of cells in your body work together?muscle cellDifferent tissues work together to make an organ. Muscle tissue, nerve tissue and blood tissue make up the stomach.Organs work together to make an organ system.What organ system is the stomach part of?stomachTEACHER’S NOTESmention other types of blood cells and tissues formed e.g. nerve
23 Name a cell that would be suitable for each job. 7A Building living things - Different cells for different jobsName a cell that would be suitable for each job.TEACHER’S NOTESAnswers:Job No1 – Nerve cellJob No2 – Egg cellJob No3 – Palisade cellJob No4 – Root hair cellJob No5 – Red blood cell
24 So where do all the cells come from? 7A Building living things - How are new cells made?All living things (including you and your teacher) started as one tiny cell!So where do all the cells come from?Living things grow and repair themselves by an amazing process called cell division.
25 7A Building living things - How are new cells made?