5. Conception to late childhood

Physical development from conception to birth

• Physical changes that occur from conception to birth involve a series of orderly and predictable changes

• Infancy: (birth – 2 years)• Early childhood: (2 – 3 years)• Middle childhood: (3 – 6 years)• Late childhood: (6 – 12 years)

Conception and fertilisation

• Human growth and development begins occurring before birth

• A sperm cell is the male gamete• An ovum is the female gamete• Fertilisation occurs when a sperm penetrates

an ovum• At fertilisation, the sex of the new individual is

determined

Prenatal development

• Germinal stage : starts at conception and ends when the blastocyst implants on the uterine wall

• Embryonic stage : lasts about 2 months after conception

• Foetal stage: Continues until birth

Germinal stage

• The cell formed at conception is called a zygote

• The zygote divides into two cells and continues to divide rapidly until it forms a solid ‘ball’ called a morula

• By about the fifth day, the organism is called a blastocyst

• The blastocyst implants on the uterine wall

Embryonic stage

• Once implantation has occurred, the organism is known as an embryo

• This period lasts for about 2 months and is characterised by rapid growth and development – the embryo develops the structure and characteristics of a human being

• By the end of this stage, all major organs are present and will continue to develop

Foetal stage

• Begins in the 9th week of pregnancy and continues until birth (full term = 40 weeks)

• At this stage, the embryo is known as a foetus• During this stage, the foetus grows from 5

centimetres long to approximately 50 centimetres long at birth

Physical changes from birth

• Neonate: the term used to describe a newborn baby (birth – 4 weeks)

• Key adjustments after birth:– Nutrition– Circulation and respiration– Temperature control– Removal of body wastes

Physical changes during infancy and childhood

• Physical growth and development– Height– Weight– Changes to body proportions– Changes in body composition– Motor development

Social development

• Social development begins at birth when an infant begins to interact with others

• Occurs in a number of ways, including:– Observation– Direct instruction– Identification

• Aspects include: gross and fine motor skills, language, cognition, emotions, relationships, behaviour

Emotional development

• Emotional development is the progressive change that occurs in a person’s ability to understand and control feelings

• Self-concept: the picture an individual has of themselves; viewing ourselves in a ‘special’ mirror

• Self-esteem: how good an individual feels about themselves

Intellectual development

• Also known as cognitive development• Infants: begin exploring the world by using

their senses• Early and middle childhood: children ask many

questions • Late childhood: children begin to reason and

perform more complex operations

The principles of individual human development

• Developmental changes are progressive and orderly and coherant

• The four main characteristics of development:– Development is about change– Development is continuous and gradual– Development is cumulative– Developmental patterns are orderly and

predictable

Health status of Australia’s children

• Many factors combine to influence the health and development of children

• Australian children generally experience good health

• Some key health concerns: communicable diseases, injuries, overweight and obesity, insufficient physical activity, poor nutrition, mental health issues, chronic illness