MeldrumAcademy

Science Faculty

S2 - Our Body

Name: ……………………………………………..

Class: …………………………………

Processes of Life Learning Outcomes / 
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X / 
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X / 
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X
Level D
1)Describe the main changes that occur during puberty
2)Describe fertilisation in animals and name where that takes place
3)Explain what menstruation is
4)State the sequence of the main stages of reproduction in humans
5)Explain the role of the placenta during pregnancy
Level E
1)Identify an animal cell and label its parts
2)Identify male reproductive system organs and state their function
3)Identify female reproductive organs and state their function
Level F
1)Describe a type of cell and give the function it is adapted for
2)State the number of chromosomes in human body cells
3)State the number of chromosomes in human sex cells and explain the importance of this number
4)Describe where the chromosomes in a fertilised egg came from
5)Describe what genes are and where they are found
6)Explain the difference between dominant and recessive genes

Revision on animal cells

All cells possess a nucleus, cell membrane and cytoplasm.

  1. Label the 3 main features of the animal cell above.
  1. Note the function of the: -
  • Nucleus
  • Cell membrane
  • Cytoplasm
  1. How can you tell that this is an animal cell and not a plant cell?

Special cells for special jobs

Use class resources to find out the name and function of each of these cells and how they are specialised for their job.

Cell Type / Name / Function / How it is specialised for function
Cells and tissues

1 What is a tissue? Give an example of some tissues.

2 Name an organ found in the human body and list the 3 types of tissue that make up this organ.

3 Explain the difference between an organ and an organism.

Organs of the body

Follow the instruction in the Practical and Activities booklet page 2 to complete the model of the body and its organs.

2. Complete the table to show the functions of each of the organs you have included on your model body.

Organ / Function

Human reproduction

Two special types of cells are sperm cells and egg cells. They each carry half

of the information to make a new person. Without these you would not exist.

For a baby to be made a sperm cell and an egg cell have to meet and become

fused together. The whole process of making babies is called reproduction.

Watch the video on “reproduction”.

Your teacher will show you some models of the human reproductive system.

listen carefully to this, in particular the names of the different parts and

what their job is.

  1. Use these words to label the diagram of the female reproductive organs: ovary vagina uterus cervix oviduct

Female reproductive system

If you need help you could turn to page 78 of Starting Science book 1.

2. Use these words to label the diagram of the male reproductive organs:

sperm duct urethra scrotum penis testes

Male reproductive system

3. Look at the list of word below. Draw a line to match each word to its function. Use a different colour for each matching pair.

Word Meaning

vaginaplaced in the female when mating

uteruswhere the egg is fertilized

ovarycarries sperm out of the body

oviductproduces eggs

penismake liquid for sperms to swim in

testesneck of the uterus

sperm ductpenis is put here when mating

urethrathe baby develops here

cervixwhere sperms are made

Copulation

Your teacher will discuss with you the process of copulation or mating.

Collect Starting Science book 1 and read page 79 then answer the questions.

1 What is sexual intercourse?

2 a Explain how an erection happens.

b Why is an erection important?

3 What is:-

a an ejaculation

b an orgasm

Human Fertilisation

Read the information on page 4 of the Practical and Activities booklet then complete the activities below.

  1. Note the meaning of “Fertilisation”
  1. Diagram of the fertilisation process.

  1. Write a brief description of fertilisation.

Menstruation

A female produces on average one egg every month. Only a few if any will be fertilised. When an egg isn’t fertilised menstruation occurs.

Read page 81 of Starting Science book 1.

Use the information to design a table to show what happens at each stage of the menstrual cycle.

Pregnancy

After the fertilised egg has travelled down the oviduct to the uterus it becomes implanted in the uterus lining. The cells continue to divide until the developing baby starts to look human and is now called a foetus. It is connected by an umbilical cord to the placenta. The placenta allows food and oxygen to be passed from the mother blood to the foetus and waste from the foetus to be passed to the mother’s blood. The foetus is protected by a fluid filled sac called the amniotic sac, or amnion, and by the bones and muscles of its mother.

1. With your teachers help, label the diagram with these words: -

amniotic sacfoetus umbilical cord placenta

2. Write notes about human pregnancy. Page 80of Starting Science 1 may help.

  • The developing baby is protected by ……..
  • The umbilical cord ….
  • The placenta……
  • Pregnancy in humans lasts for …..

Puberty

Many changes take place during puberty in both boys and girls that lead to their development into men and women. These changes are both physical and emotional.

Think about the types of changes that might happen. Your teacher will make a list of all the changes you can think of. Illustrate the bodies below to show the physical and mental changes that take place in boys and girls and where they affect.

males females

What’s in the nucleus?

We are going to look at what is found inside the nucleus of all living cells.

nucleus

You already know that the function of the nucleus is to control all the activities of the cell. To do this it carries all the genetic information required to make an organism. So the nucleus of a cell carries a blueprint of life. Every cell in your body contains all the information needed to make an exact copy of you!

The genetic information in the nucleus is carried in DNA.

The DNA is coiled up into structures called chromosomes. Different organisms have a different number of chromosomes in their nucleus

e.g. humans have 46 (23 pairs), fruit fly have 8 (4 pairs), and chimpanzees have 48 (24 pairs).

Chromosomes carry 100s of genes, which contain the instructions for one particular characteristic.

Find out

  1. What DNA stands for?
  1. What a gene is, where is it found and what does it do?
  1. Make a model of DNA. There are instructions on page 5 of the Practical and Activities booklet, but if you like you could make your own from junk.

Matching chromosomes

Humans have 46 chromosomes shown in the diagram below.

Follow the instructions on page 7 of the Practical and Activities booklet to makes a human karyotype (a map of your chromosomes).

Human Karyotype (stick your chromosome pairs here)

EXTRA Chromosomes and fertilisation

Humans have 46 chromosomes, which carry all the information to make us! Half the information comes from our father’s sperm and half comes from our mother’s eggs. These join together at the point of fertilisation.

1)a) How many chromosomes are in (i) human body cells?

(ii) human sperm and egg cells?

b)Why is this difference in number important? (Think about fertilisation)

2)Complete the diagram below to show the number of chromosomes in sperms and eggs.

3)Draw two more arrows and a new single cell to show what would happen if fertilisation took place between the sperm and the egg.

4)An embryo and then a baby develop from the fertilised egg cell. How many chromosomes will it have in its skin and liver cells?

Inheritance of characteristics

We inherit all our characteristics from our parents through the chromosomes we get when the sperm and the egg join at fertilisation. We get a gene from each parent for each characteristic. We don’t end up being a blend of our parents though! This is because some characteristics are dominant over others that are recessive.

Check out these.

DOMINANT TRAITS / Number in class / RECESSIVE TRAITS / Number in class
eye colour / brown eyes / grey, green, hazel, blue eyes
hair / dark hair
non-red hair
curly hair
widow's peak / blonde, light, red hair
red hair
straight hair
normal hairline
facial features / dimples
unattached earlobes
freckles
broad lips / no dimples
attached earlobes
no freckles
thin lips
  1. Find out how many people in the class have the dominant and recessive characteristic for each of these.
  1. Do you notice a difference between the number that have the dominant characteristic to the number that have the recessive?

Your teacher may demonstrate why this happens using the attached or unattached earlobe activity.

Making babies activity

It is a totally random process that controls if we inherit dominant or recessive genes from our parents and so which characteristics we have. We can imitate this process using the toss of a coin.

Refer to page 10 in the Practical and Activities booklet in order to give the baby below its characteristics.

Feature / Gene from Dad / Gene from Mum / Genes in baby / How it looks
eye colour
hair colour
hair type
dimples
freckles

Look at all the babies in the class and comment on the number of dominant and recessive characteristics.

EXTRA - Your teacher may show you how to work out what offspring might look like in a simple genetics cross. Then try the “Predicting what offspring will look like” examples on page 11 of the Practical and Activities booklet.

Keeping the body working Learning Outcomes / 
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X / 
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X / 
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X
Level D
1)Explain the purpose of digestion
2)Name two ways that food is broken down
3)Name the 4 types of teeth
4)Describe the shapes and functions of different teeth
5)Identify the skull of a herbivore and of a carnivore
6)Identify these organs of the digestive system - mouth, oesophagus, stomach, liver, small & large intestine & anus
7)Describe the route that food takes through the digestive system saying where it is digested and absorbed and how waste material leaves the body
8)Identify the organs involved with breathing
9)State that the purpose of breathing
10)Describe how movement of the diaphragm and rib muscles allows air to moves into the lungs
Level F
1)Give examples of enzyme controlled reactions
2)Name two factors that affect enzyme activity
3)Describe what respiration is in terms of energy
4)Name the by-products of respiration
5)State the difference between respiration and breathing

What is food?

Carry out the practical on page 13 of the Practical and Activity booklet. Write up in your jotter.

1. Find out the names of the five different food groups.

2. Construct a table to show what each type of food is used for and examples of the types of food that contain it.

3. Food is needed by every cell in or body. It is transported in our blood.

a) What must happen to food before it can be used by

our cells?

b)Find out the two ways that our digestive system do this.

Teeth – Making food smaller

1) There are 4 different types of teeth. Name them.

2a) Below is a picture of the human jaw. Colour and label the 4 different types of teeth. You may create a key.

b) Complete the table showing tooth function in humans.

Type of tooth / Function
Incisor
Canine
Premolar
Molar

3) Below are pictures of the skulls of a carnivore and a herbivore.

Label which one is which and explain how you decided which was which.

EXTRA “Sugar and tooth decay activity” – page 14 in Practical booklet.

Structure of the digestive system

1. Below is a picture of the human digestive system. Use class resources to label the organs.

2. Describe the route that food takes from the mouth through the

digestive system and what happens at each organ.

3. What is the role of the liver and pancreas?

The chemical digestion of food

Carry out the practical “Making a model intestine” on p 15 of the Practical and Activities booklet. Write up the experiment in your jotter.

From the experiment you should have found that starch is too big to pass through the model intestine. This means it would also be too big to pass into the blood and through cell membranes.

To solve this problem our bodies make special digestive chemicals called enzymes. Enzymes are used in digestion to breakdown food into small enough pieces to pass into the blood.

1. In the mouth, saliva contains an enzyme that helps break down starch into sugar. Find out what that enzyme is called and note above the arrow.


large starch molecule small sugar molecules

2. Design an experiment using a model visking tubing cell that would prove that amylase breaks down starch into sugar.

Draw a diagram of your experiment and briefly describe what youwould do to show that starch has been broken down into sugar. (Do in your jotter).

3. a) Find out the names of the enzymes that digest protein and fat.

b) What smaller particles are proteins and fats broken down into?

INVESTIGATION
Factors that affect how well enzymes work

Carry out the experiments How temperature effects enzymes and How pH affects enzymeson pages 17 and 19 in the Practical and Activities booklet. Write these up in your jotter.

OR

Design and carry out an investigation into the effects of temperature OR pH on how well amylase enzyme works.

  1. Describe the effect of different temperatures on how well amylase enzyme worked. Note the temperature it worked best at and explain why this was the case.
  1. Describe the effect of different temperatures on how well amylase enzyme worked. Note the temperature it worked best at and explain why this was the case.

Introduction to respiration

The food we eat has lots of stored energy locked up in it. Respiration is the process that releases the energy stored in food so that it can be used by our cells for lots of different activities.

Respiration needs oxygen and produces carbon dioxide and water.

  • Note down the things we need energy for.

Comparing Inhaled and exhaled air

Carry out the “Burning candle experiment” and the Huff and puff experiment on page 21of the Practical and Activities booklet. Write both up in you jotter.

  1. Complete the summary table by choosing the appropriate word

Type of air / Oxygen / Carbon dioxide
Inhaled (normal) / (more / less) / (more / less)
Exhaled / (more / less) / (more / less)
  1. Why has the level of oxygen changed in the way it has?
  1. Where has the extra carbon dioxide come from?

EXTRA

Your teacher may show you how to use digital sensors to compare the levels of oxygen and carbon dioxide in inhaled and exhaled air more accurately.

Design an experiment using the sensors to investigate if gas exchange only happens in living organisms or not.

The breathing system

The diagram shows the main parts of the breathing system and some of the bones in the chest.

1) Label the diagram with the words below.

air sacs diaphragm lung bronchus

musclesrib trachea (windpipe)

2) Construct a flow diagram to show the flow of air from being

breathed in to being breathed out. Include where oxygen and

carbon dioxide goes. Include pictures if you want.

Breathing Movements

Sit quietly, put your hands on your ribs and take a deep breath in.

This is called inhaling. Notice what happens to your chest.

Breath out again – this is called exhaling. What happens to your chest now? What do you think is moving your chest in this way?

1. Study the 2 pictures. Label the diagram to show which shows inhaling and which shows exhaling.

  1. a) Name the parts labeled X and Y on your diagram.

b) Describe what happens to X and Y when someone

i)inhales

ii)exhales

EXTRA“Air sacs” activity, p 23 of practical guide book.

Summary of Respiration

  1. Complete the diagram below to show the 2 things that are needed for respiration and the 2 waste products that are produced.
  1. Colour the raw materials arrows green and the waste product arrows red.
  1. Complete the summary below.

Respiration is the release of ______from food. It takes place inside every living ______.

It can be summarized by the following word equation:

______+ ______+ ______+ energy