Development Flashcards
What skills develop as children grow up?
- Motor
- Perceptual
- Language
- Cognitive
- Social
In neurological development, what is the process of addition?
Ongoing accumulation or growth (myelination and dendritic aborisation)
In neurological development, what is the process of regression?
Initial overproduction followed by elimination of redundant elements such as neurons and synapses
What are causes of atypical development?
- Antenatal exposure to teratogens, drugs or alcohol
- Poor maternal health
- Child abuse or neglect
- Genetic factors
- Nutrition
- Perinatal complications
- Infections
- Unknown
What are the 4 types of abuse?
- Psychological
- Physical
- Sexual
- Neglect
What are the four developmental domains?
- Gross motor
- Fine motor and vision
- Hearing and language
- Social and emotional
In what five steps does language develop?
- Preverbal communication
- Phonological development
- Semantic development
- Syntax and grammar development
- Pragmatics development
When do babies often say their first word?
9-13 months
How many new words are babies learning at 12-18 months?
3 per month
How many words does an infant know at 18 months?
22
How many words does a baby learn per week after 18 months?
10-20 per week
What s the vocabulary range at age 6?
10000 words
What are the 4 stages of child development?
- Infancy (0-2): attachment, maturation of sensory, perceptual & motor functions & understand objects through senses
- Early childhood (2-6) - locomotion, fantasy play, language
development, sex role identification & group play - Middle childhood (6-12) - friendship, skill learning, self-evaluation,
team play, understand cause & effect & conservation - Adolescence (12-18) - physical maturation, emotional development, peer group & sexual relationships, understand abstract thinking
What are, according to Piaget, the 4 concepts of learning how to think?
- Scheme - internal cognitive structure which provides procedure to use in specific circumstances
- Assimilation - process of using scheme to make sense of event or experience
- Accommodation - changing scheme as result of new information
- Equilibration - process of balancing assimilation and accommodation to create schemes that fit environment
What are, according to Piaget, the 4 stages of learning how to think?
- Sensorimotor
- Preoperational
- Concrete operations
- Formal operations
What is the epigenetic mechanism?
Changes to the genome that affect gene expression without changing the DNA sequence
What is the effect of histone methylation?
Less gene expression
Histone methylation increases the positive charge on histones, increasing the interaction with DNA and making it less available for transcription
What is the effect of histone acetylation?
More gene expression?
Histone acetylation reduces the positive charge on histones, decreasing the interaction with DNA and making it more available for transcription
What is X-chromosome inactivation?
Random silencing of one X chromosome to enable normal development in females
What is genomic imprinting?
Gene expression from the paternal copy is not the same as gene expression from the maternal copy
Imprinting means it is silence → maternal imprinting means the paternal gene copy is being expressed and vice versa
What does imprinting decide?
What copy of a gene is being expressed
What is Prader Willi syndrome?
Maternal imprinting on chromosome 15
What are the symptoms of Prader Willi syndrome?
- Obesity
- Constant hunger
- Short individuals
What is Angelman syndrome?
Paternal imprinting on chromosome 15
What are the symptoms of Angelman syndrome?
Happy, mental retardation
What are two epigenetiv changes in cancer?
- Gross reduction of methylation
2. CpG-specific changes (abnormal methylation in tumour suppressor genes)
What are the three steps of sex determination?
- Gonad formation
- Gonad determination
- Sexual differentation
What cascade does SRY trigger?
SRY activates Sox9 (chromosome 17, both sex chromosomes). Dax1 (on Y chromosome) also essential (dose sensitive, needs to be normal)
How is AMH produced in males?
Developed testes
What chromosome disorders can occur?
- A whole chromosome
- Region of a chromosomoe
- Change in a single gene
What is genetic profile of Klinefelter?
47 XXY
What are the clinical features of Klinefelter?
- Normal at birth, higher incidence of undescended testes
- Tall stature
- Pea-sized testes
- Lack of secondary sexual characteristics
- Gynaecomastia (breast tissue development)
- Infertility
- Some behavioral and minor learning difficulties
What happens in 5-alpha-reductase disorders?
- Internal structures male
- Variable appearance of external genitalia at birth
- During puberty increased androgen levels lead to virilisation of external genitalia
What is virilisation?
the development of male physical characteristics (such as muscle bulk, body hair, and deep voice) in a female or precociously in a boy, typically as a result of excess androgen production.
What is Ovotesticular DSD?
Ovarian and testicular tissue in the same individual
What is the prognosis for someone with Ovotesticular DSD?
The presence of structures derived from the Wolffian ducts and the degree of virilisation will depend on the production of Testosterone
What is 46 XX testicular DSD?
- Goes down the path of developing testes
- Will develop all internal male genitalia
What is 46 XX gonadal dysgenesis?
- Failure of ovarian development
- Internal organs derived from Mullerian structures
- Female external genitalia
- Present with delayed puberty, primary or secondary amenorrhea
- As no ovaries are not developed
What happens in 21-hydroxylase deficiency?
fetal androgen excess
Virilisation at birth
What are two causes of fetoplacental androgen excess?
- Aromatase deficiency
2. Cytochrome p450 oxidoreductase deficiency
What can happen in 46 XY DSD?
- Complete gonadal dysgenesis
- Partial dysgenesis
- Gonadal regression
What are the sexual characteristics of androgen insensitivity syndrome?
Testes and ovaries, but no other structures
Externally female
What happens in puberty in someone with androgen insensitivity syndrome?
Testes become active and secrete androgens, aromatised into estrogen
What happens in partial androgen insensitivity syndrome?
External genitalia can be female, male or both
What are the internal genitalia for someone with 5-a-reductase deficiency?
Male
What are the external genitalia for someone with 5-a-reductase deficiency?
Variable
