C. GENETICS AND GENETIC COUNSELING Flashcards
Alleles
pairs of genes
There are 2 genes for every human trait:
from the ovum and the sperm
Chromosomes
located in the nucleus of the cell
carry the hereditary material that determines the
individual’s physical characteristics
deoxyribonucleic acid
the genetic information that
every parent passes on to their biological children
Cytogenetics
study of inheritance in relation to the structure and
function of chromosomes
Dermatoglyphics
study of skin markings or patterns on fingers, hands, and
feet, and its application, especially in criminology
Genes
small segments of DNA contained in the chromosome
dominant, recessive, sex-linked
Genetics
branch of biology|
study of genes,
Genotype
refers to the genetic makeup of an organism
an organism’s complete set of genes
Genome
complete set of genetic information in an organism
Heterozygous
state of having inherited different forms of a particular
gene from each one of your biological parents
Homozygous
a genetic condition where an individual inherits the same
alleles for a particular gene from both parents
Imprinting
an epigenetic phenomenon that causes genes to be
expressed in a parent-of-origin-specific manner
Isochromosome
an unbalanced structural abnormality in which the arms
of the chromosome are mirror images of each other
Consequently, there is partial trisomy of the genes
present in the isochromosome and partial monosomy of
the genes in the lost arm.
Karyotype
an individual’s collection of chromosomes
a laboratory technique that produces an image of an
individual’s chromosomes
Phenotype
an individual’s observable traits, such as height, eye
color, and blood type
The genetic contribution to the phenotype is called the
genotype.
Meiosis
a type of cell division that reduces the number of
chromosomes in the parent cell by half and produces
four gamete cells
Mosaicism
a condition in which cells within the same person have a
different genetic makeup
This condition can affect any type of cell, including:
Blood cells, Egg and sperm cells
Nondisjunction
failure of homologous chromosomes or sister chromatids
to separate subsequent to metaphase in meiosis or
mitosis so that one daughter cell has both and the other
neither of the chromosomes
s in the nucleus of the cell, carry the
hereditary material that determines the individual’s
physical characteristics. They are threadlike strands of
DNA.
Chromosomes
Normal embryonic cell tissue contains
46 chromosomes
(23 pairs)
Normal embryonic cell tissue contains 46 chromosomes
(23 pairs):
44 homologous (22 pairs)
2 sex (1 pair) chromosomes
The sex of the fetus is determined at the time of
___ by the combination of the sex chromosomes
of the sperm (X or Y) and the ovum (X or X). The resulting
pair of sex chromosomes is either XX (female) or XY (male)
fertilization
Mendelian laws
← allow us to predict inheritance of
characteristics such as eye and hair color
can also predict whether the child will be born with a
genetic disorder
PRINCIPLE OF MENDELIAN INHERITANCE
Law of Segregation
2 alleles for each gene are placed in different
gametes
PRINCIPLE OF MENDELIAN INHERITANCE
Law of Independent Assortment
inheritance of 1 gene does not affect the inheritance
of any other gene
PRINCIPLE OF MENDELIAN INHERITANCE
Law of Dominance
when 2 different alleles are present, only one is
dominant and will be expressed
Chromosomal Inheritance Disorder
Modes of Inheritance
Autosomal dominant
Autosomal recessive
X-Linked Dominant
X-Linked Recessive
Multifactorial
