Exam #2 Flashcards
1
Q
Heredity
A
genetic disorders/ inherited disorders are disorders that can be passed from one generation to the next
- disorder in the gene or chromosome structure
- alterations of a whole chromosome, a part of a chromosome or even a single gene manifest as a genetic disorder
2
Q
Chromosomes
A
44 autosomes (22 pairs) 2 sex chromosomes (1 pair)
3
Q
Phenotype
A
expression of the gene (appearance of the gene)
4
Q
Genotype
A
composition of the gene
5
Q
Genome
A
Complete set of genes
6
Q
Homozygous
A
two like genes for a trait
7
Q
Heterozygous
A
Unlike genes for a trait
8
Q
Dominant
A
dominant in their action over others
9
Q
Recessive
A
a gene that is not dominant
10
Q
Autosomal dominance
A
- person with dominant gene for a disease is usually heterozygous
- huntington’s chorea, OI, marfan syndrome
- one dominant gene and one healthy gene
11
Q
Two dominant genes mean….
A
never good
-baby will not survive
12
Q
Autosomal recessive
A
- most genetic disorders are inherited as recessive traits
- does not occur unless 2 genes for the disease are present
- many unborn errors (cystic fibrosis, tay sachs, galactosemia, pku)
13
Q
X-linked dominant (sex linked dominant)
A
- some genes for disorders are located on and transmitted only be female sex chromosome (X)
- no carriers in X linked dom.
14
Q
X-linked recessive
A
- majority of x-linked disorders are recessive
- female- normal gene also present blocks expression of the disease
- Only male children will have the disease
- muscular dystrophy, hemophilia
- daughters are the carriers but not affected
15
Q
Multifactorial (polygenic)
A
- congenital disorders present at birth, heart disease, HTN, DM, Pyloric stenosis, cleft lip/palate, NTD, mental illness
- Environmental influences determine if the disorder is expressed
