CAMBRIDGE Health and Human Development Units 1&2 WEBSITE

SOLUTIONSCHAPTER 7 SUMMARY QUESTIONS

1. List and briefly explain the principles of development.

Cephalocaudal law of development: the direction of development that occurs from the top (head) down to the bottom (toes) of the body.

Proximodistal law of development: the pattern of development that occurs from the centre (or inside) of the body and extends to the body’s extremities.

2. Identify two examples of each principle of development.

Cephalocaudal: the child gains control of the head first, then the trunk and arms, and then the legs head grows first, followed by trunk and so on.

Proximodistal: arms develop before the hands and the hands develop before the fingers torso will grow before the limbs grow.

3. Using diagrams, explain the process of conception.

Diagrams will vary but should include the following points: rising levels of progesterone prepare the uterus to support a fertilised ovum and ovaries

ripen oval in fluid-filled sacs called follicles midpoint of a woman’s cycle, ovulation occurs, at this point, the ovum is swept into the

fallopian tube where it waits 12–24 hours to be fertilised conception is most likely to occur if sexual intercourse occurs one to three days prior to

ovulation the ‘fittest’ sperm fertilises the egg, and a chemical reaction takes place to disallow any

other sperm to penetrate; at the same time, the tail of the sperm detaches, leaving only the head in the egg

the 23 chromosomes from the sperm and 23 chromosomes from the ovum unite to make 46 chromosomes that contain the genetic blueprint of a new individual, including its sex.

4. Identify and explain each of the stages of prenatal development.

Germinal stage: the first stage of prenatal development measured from the movement of conception until implantation (about two weeks post-conception).

Embryonic stage: the second stage of prenatal development measured from implantation (about two weeks post-conception) until the end of the eight week after conception.

Foetal stage: the third stage of prenatal development measured from the end of week 8 until birth.

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CAMBRIDGE Health and Human Development Units 1&2 WEBSITE

5. Copy and complete the following table, identifying the development that occurs in each stage.

GERMINAL STAGE EMBRYONIC STAGE FOETAL STAGE Cell division occurs Differentiation occurs Blastocyst moves

down the fallopian tubes

Blastocyst attaches to the endometrium (implantation)

Once implantation occurs the embryo begins receiving nourishment

Foundations are laid for future growth and development

Beginnings of placenta are formed

Amniotic sac fills with fluid

Thyroid gland appears

Heart appears, begins to function and divides into chambers

Sections of the brain are recognisable

Respiratory system begins to develop

Main organs begin to grow

Limb buds begin to form

Pituitary gland and muscle fibres form

Embryo begins to move

Webbed fingers and toes

Teeth and palate form

Extensive growth and development of organ systems

By end of this stage, all muscles, organs and nerves are beginning to function

Hands can be bent at wrist

Webbing on fingers and toes disappears

Eyelids to cover eyes Brain continues to

grow and develop Respiratory system

differentiates Gastrointestinal tract

begins to function

6. What is the placenta? Explain its function.

The placenta is a vital organ that supplies oxygen and nutrients to the developing embryo and removes waste products. It is formed from a layer of the developing embryo and links it to the circulatory system of the mother until birth.

7. List and briefly explain the adaptations a baby needs to make immediately after birth.

Respiration: once umbilical cord is cut, the infant must take its first breath and inflate its lungs.

Circulation: when umbilical cord is cut there is a change in blood pressure. With first breath comes an increase in blood supply to the lungs, then the opening between the left and right side of the heart is closed causing a change in the blood flow through the heart.

Digestion and removal of waste: must adapt to drinking and digesting milk. A number of organs take on their new roles and share the task of removing waste from the body. The lungs excrete carbon dioxide and the kidneys purify the blood and the baby will start to pass urine. As a result of ingesting milk, they will also begin to use their bowel.

Temperature control: due to large surface area, wet skin and low fat stores, the baby’s temperature will fall, but should return to normal over the next few hours.

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CAMBRIDGE Health and Human Development Units 1&2 WEBSITE

8. Explain what innate reflexes are and provide examples.

Innate reflexes are actions that a neonate displays automatically. Sucking, grasping, rooting and blinking are examples of such reflexes.

9. Copy and complete the following table, identifying examples of each component of development at each stage.

Answers will vary for each student. Below are some examples of what students might include, as examples of each component of development at each stage.

Physical Social Emotional IntellectualBirth – 12 months

Bones become much harder and stronger

Awareness of others and enjoys interacting with adults

Difficult knowing how to respond when they become angry or frustrated

Number of words they can understand increases

1–6 years Maintain balance while moving quickly, can hold balanced position for 8–10 seconds

Broader range of social skills

Maintain closeness to a few special adults

Speak in more complex sentences

6–12 years Secondary teeth begin to replace primary teeth

Increased sense of independence

More competent at identifying and understanding the emotions of others

Use logical thinking process and develop abstract thoughts

10. Identify some examples of development that occur around five years of age and explain how they assist in preparing a child for school.

Student answers will vary depending on which examples they choose. Below are a couple of example they may use.

Mature form when walking and running and can walk backwards with speed: important in preparation for school as once students begin school they are included in Physical Education/Sport activities; having these basic skills allows active, confident participation in these activities.

Confidence to experience new situations: a child may enter a group of children and ask to participate in a game, which is important aspect of socialisation.

Learning to follow multi-step instructions: means they can listen to and follow teacher instruction when they begin school.

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