SECTION CONTENT AND QUESTION ANSWERS

New Life: Baby Chicks

The Embryo

Key Terms: cells, blood vessels, oxygen, fertilised, yolk, womb, gestation period, larvae, incubated, temperature.

Questions and Answers:
1. Which two things do all growing embryos need?
Food and oxygen to grow

2. What is the yolk's job in the egg?
The yolk provides food for the developing chick

3. Why does the egg yolk get smaller as the chick grows?
As above, so the yolk reduces in size as it is absorbed/eaten by the embryo/chick.

4. How does a chick embryo get the oxygen it needs?
The oxygen needed travels to the chick embryo through the egg/shell.

5. How does a human embryo get the oxygen it needs?
Through the mother's blood.

6. Which creatures produce embryos that grow into larvae?
The embryos of insects and amphibians grow into larvae, such as caterpillars, maggots, or tadpoles.

Incubation

Key Terms: humidity, climatic conditions, temperature, oxygen, carbon dioxide, gas exchange, bacteria, viruses, disinfectant.

Questions and Answers:

1. Which two gases are exchanged in the incubation process?
Growing embryos need oxygen and give off carbon dioxide.

2. Why should the eggs be turned regularly?
Turning the eggs regularly is vital so that the egg is incubated evenly and the embryo does not get stuck to the shell membrane.

3. What can be used to measure humidity?
A hydrometer can be used to measure humidity.

4. How do climatic conditions affect humidity?
Rain/wet conditions contribute to high humidity; hot/dry conditions contribute to low humidity.

5. Why should humidity be as high as possible on the 20th day?
The humidity should be as high as possible at hatching (19th-21st days) in order to keep the membrane under the shell moist and therefore easy for the chick to open.

6. What is 'Candling' used for?
Candling is used to check how/if the embryo is developing - a small bright torch is held to the shell in a dark room.

After Hatching

Key Terms: energy, absorbing, appliance, conditions, fuels, notes, mood, nourishing, plumage, feeding programme.

Questions and Answers
1. Why do chicks need no food for the first 24 hours?
No food is needed for the first 24 hours after hatching because the chicks are still absorbing the last of the yolk.

2. Which two things are used by the chick to hatch out?
Energy and its egg tooth are used by the chick during hatching.

3. What is a 'brooder' and why is it important?
The brooder is a device designed to provide heat for the chicks in the absence of the natural mother.

4. How can a brooder be heated?
The brooder can be heated by a variety of fuels - paraffin, oil, or an electric source such as a dull emitter bulb.

5. Which signs can show whether the chicks are happy?
The notes/sounds made by the chicks vary according to their mood. This is also highlighted by their relative position.

6. What do you understand by the term 'nourishing'?
Various answers can be expected here depending on the students previous level of knowledge, but should encompass the sustaining effect of foods etc.

What are Chickens?

Key Terms: sexual differences, egg structure, porous, incubation, brooding, feeding, proteins, carbohydrates, fats, minerals, vitamins, anatomy.

Questions and Answers:
1. What differences can be observed between a male and female chicken?
Male has larger comb than the female and hackles of long, pointed feathers; Male has larger tail feathers and these are more resplendent than the female's.

2. What are the special qualities of a good quality bird?
Good stance with erect head; well spread legs; deep long body; flat back; long deep breast; bold prominent bright eyes; keen alert appearance.

3. Which two reserves of food are present in an egg?
The yolk and the albumen (white) are both food reserves composed of protein substances.

4. How is the yolk of the egg kept in the middle and why is this important?
The yolk is maintained in suspension at the centre of the white by strands of albumen known as chalazae. This is important so that the embryo is protected from damaging movement.

5. How does a chick break free from the egg?
The chick uses its strong egg tooth at the point of the upper beak. This falls off shortly after hatching.

6. What should the chicken food provide?
The food has to provide the material for growth, the maintenance of the body, and for the manufacture of eggs.

7. What is the function of the gizzard?
With the help of strong muscular walls and the stones and grit, the gizzard grinds the food into a pulp before it passes further along the alimentary canal.

Extraordinary Eggs

Key Terms: design, structure, cell nucleus, fertilised, germinal disk, proteins, carbohydrate, mass, calcium carbonate, marble, limestone, coral, chalk, embryo, porous, preservative, decomposition.

Questions and Answers:
1. Why are eggs nutritious to eat?
Designed to provide nutrition for the embryo; yolk and albumen are food reserves; an egg consists of proteins, mineral elements, and carbohydrate.

2. Why is the egg a strong structure?
Shaped as an elliptical cone and structured to provide protection for the developing embryo; shell made from calcite which is also found in marble, limestone, coral, and chalk.

3. What would cause an egg to decompose?
The blocking of the shell pores (e.g. by preservative) would prevent the entry of any air which might cause decomposition.

4. What is the air space for?
The air space provides air for the young chick/embryo to breath.

5. What differences can you see between the fresh and stale egg?
Observations can include: white (albumen) more solid and round in fresh egg; stale egg flatter; bigger air space in stale egg; chalazae can be seen in fresh egg.

6. How many creatures can you think of that lay eggs?
Answers could include: birds of various species, amphibians, marsupials, insects, reptiles etc.

Poultry Postage Stamps

Notes: No questions are given here. The intention is that this section can be used as a genuine cross-curricular resource, whether for Art and Design (looking at the colours, design of the actual stamps), English (looking at the language and story), or Religious Education (looking at the beliefs of the people in the story).