Chapter 3: Foundations of Development Flashcards
What are phenotypes?
Directly observable characteristics
What is genotype?
The complete set of genes or the genetic makeup of an organism
What do chromosomes do?
Store and transmit genetic information
What is DNA?
Long double stranded molecule that looks like a twisted ladder. Each rung of the ladder consists of a pair of chemical substances called bases.
What is gene?
A segment of DNA along the length of the chromosome
What is mitosis?
A unique feature of DNA that it can duplicate itself
What are gametes?
Sex cells - sperm and ovum
How are gametes formed?
Meiosis, which haves the number of chromosomes normally present in body cells.
What is the product of fertilisation?
Zygote
Which pair of chromosomes are sex chromosomes?
23rd
What is an allele?
Each form of a gene in the chromosome
What is dominant-recessive inheritance?
Only one allele affects the child’s characteristics - it is called dominant; the second allele is recessive
What is incomplete dominance?
When both alleles are expressed in the phenotype, resulting in a combined traits or one that is intermediate between the two
Who is more likely to be affected by X-linked inheritance?
Males are more likely to be affected because their sex chromosomes do not match
What is genomic imprinting?
When alleles are imprinted so that one pair member is activated regardless of its makeup
What is mutation?
A sudden but permanent change in a segment of DNA
What is the age of viability?
The point at which the baby can first survive
What is the Apgar scale used for?
To assess the baby’s physical condition
What is the breech position?
Where the buttocks or feet will be delivered first
What are preterm infants?
Born several weeks or more before their due date
What are small-for-date infants?
Below their expected weight considering the length of the pregnancy
What is gene-environmental interaction?
Because of their genetic makeup, individuals differ in their responsiveness to qualities of the environment
