Genetics & Embryology Flashcards
What is it called with there is an extra chromosome?
trisomy
What is it called when there is a missing chromosome?
monosomy
What is a karotype?
A picture of a person’s chromosomes derived from a blood sample
Which chromosome tends to cause medical and developmental problems when it is in trisomy?
a sex chromosome
What are chromosomal abnormalities that can occur?
Change in the number of copies, duplications, deletions, and translocations of parts of the chromosome
What are contiguous gene syndromes?
Caused by large deletions containing several genes
What is an example of a Microdeletion contiguous gene syndrome?
Williams syndrome
What is an allele?
A copy of a gene for a trait
What are the patterns of Mendelian inheritance?
autosomal recessive, autosomal dominant, x-link inheritance
What does heterozygous mean?
Have two different alleles for the same gene.
What is autosomal recessive inheritance?
When a mutation is inherited only when both parents have an abnormal allele for the gene.
What is autosomal dominant inheritance?
Traits of the phenotype manifest when mutations are present in either of the two copies of a gene.
What is an x linked mutation?
Conditions caused by mutation in genes on the x chromosome. Woman can be carriers but likely have no affects. Affected males pass on to 100% of daughters% of sons. Affected females pass to 50% of children
What is multifactorial inheritance?
Disorders resulting from an interaction of multiple genes with environmental influences (ex: teratogens)
What age is an embryo?
0-8 weeks
What age is a fetus?
9 weeks to birth
What age is a neonate?
birth to one month
What age is an infant?
Less than 2 years
When is the primary palate roughly developed?
A few days somewhere in the 6-8 week time of development
Formation remains how it ended at 8 weeks, (if didn’t occur, will result in cleft)
What is fusion?
Tissues approach each other, regress(tissue returns to more primitive stage), and become one
What is merging?
A process of filling in without regression
What is a gene?
A discrete unit of heredity that influences a visible trait. “recipe”
HOw many genes are in the human genome?
30,000
How many nucleotide bases are in a human genome?
3 billion
What is a cemtomere?
Where the two chromosomes attach.
What are the types of chromosome dosage errors?
Monosomy, trisomy, deletion, inversion, translocation
