unit 1 outcome 2 Flashcards
what is heredity?
the transmission of characteristics from biological parents to their offspring via genes at the time of conception
what are genes?
the basic units of our genetic material
what is the interactionist approach?
both heredity and environment are important factors in development
what are chromosomes?
they are made up of DNA, and found in cells (23 pairs in each)
what is DNA?
the genetic blueprint that influences our development
what are dominant and recessive genes?
dominant genes WILL be displayed (e.g. brown eyes)
recessive genes will NOT be displayed unless there are two genes (e.g. blue eyes)
what is the difference between nature and nurture?
nature is influenced by our genetic inheritance + biological factors
nurture is influenced by external / environmental factors after birth
what are some genetic disorders?
- down syndrome
- fragile x syndrome
- alzheimer’s disease
- turner syndrome
- triple x syndrome
- klinefelter’s syndrome
- supermale syndrome
how are identical (monozygotic) twins formed?
when a single fertilised egg splits into two during the first couple of days after conception
they share 100% of their genes
how are fraternal (dizygotic) twins formed?
when two seperate eggs are fertilised by two different sperm cells
they share 50% of their genes, can be same or opposite sex and are not genetically identical
how is down syndrome caused? + effects
happens when a person inherits an extra chromosome
results in:
- mild to moderate intellectual disability
- impediments to growth and motor skill development
- congenital heart disease
- characteristic facial features
how is fragile x syndrome caused?
due to a defective single gene on the X chromosome, which has caused the x chromosome to break
what is alzheimers disease? + how is it caused?
it is the deterioration of the brain, leading to loss of memory and cognitive abilities
a gene in chromosome 14 is usually responsible
