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