Human Genetic Disorders Flashcards
______ traits are always expressed in a persons phenotype.
Dominant
How many pairs of matching homologous chromosomes are there?
22
Huntington’s disease is a _____ genetic disorder caused by a rare autosomal dominant allele (causes death)
Lethal
Dominant allele on chromosome __ is the culprit for Huntington’s disease.
4
Huntington’s disease is the deterioration of the ______ system, particularly the brain.
Nervous
Huntington’s disease results in….
Uncontrolled, jerky movements of head and limbs
Achondroplasia is a form of _______
Dwarfism
Achondroplasia is inherited as an autosomal _______ disorder.
Dominant
People who have achondroplasia have abnormally short ____ & ____ relative to other body parts.
Arms & legs
People who see and write letters or parts of words backwards have….
Dyslexia
Dyslexia is a ______ trait.
Dominant
Most genetic disorders are caused by ______ alleles.
Recessive
Cystic fibrosis is one of the most common _____ genetic disorders among Americans.
Lethal
The gene for Cystic Fibrosis is located on chromosome __.
7
In cystic fibrosis, mucus accumulates in the ________ tract and in lungs.
Digestive
During Cystic fibrosis, breathing is difficult, thickened _____ slows secretion of digestive enzymes, so food can not be digested properly.
Mucus
Treatments for Cystic fibrosis include….
Physical therapy, special diet, and new drug therapies
Most common in black Americans whose families originated in Africa and white Americans whose families originated in countries surrounding the Mediterranean Sea.
Sickle cell anemia
Sickle cell anemia is inherited as autosomal _____ trait.
Recessive
Someone with Sickle cell has red blood cells that are shaped like a sickle (half moon) not _____.
Round
The life span of sickle cells are _____.
Shorter
Sickle cell anemia clogs small blood vessels causing _____ damage and deprivation of oxygen and nutrients.
Tissue
Treatments for Sickle cell anemia include….
Blood transfusion and drug therapy
Tay Sachs is an autosomal _____ disorder.
Recessive
Tay Sachs affects the central ____ system.
Nervous
Recessive alleles result in the absence of _____ that normally break down a _____ produced and stored in tissues of the central nervous system.
Enzymes, lipid
In Tay Sachs, the lipid accumulates in the ____.
Brain
Tay Sachs results in…
Blindness, loss of movement, and mental deterioration
Symptoms of Tay Sachs begin within the __ year of life.
1st
Tay Sachs results in death before age __.
5
The allele in Tay Sachs is common among Pennsylvania Dutch people and the ____________ people.
Ashkenazi Jewish
PKU is an abbreviation for…..
Phenylketonuria
PKU results from the absence of enzymes that convert the amino acid, phenylketonuria, to ______.
Tyrosine
PKU accumulates in the body and damages the _________ system.
Central nervous
When are tests for PKU given?
At birth
Infants affected by PKU are given a diet low in phenylalanine until ________.
Their brains are fully developed
Which disorder means having no skin pigment?
Albinism
_____ results in very pale skin and white-blonde hair.
Albinism
Albinism affects ___ races.
All
An X-linked inheritance is located on the _________.
Sex chromosomes
Examples of an X-linked Inheritance disorder are…
Color blindness ; Hemophilia
Color blindness is the inability to distinguish __________.
Among some or all colors
In color blindness, mutant forms of the X-linked genes change the light-absorbing of sensory ______ inside the eyes.
Receptors
Normally, humans can detect differences among ___ colors. One with red-green color blindness sees fewer than __ colors.
150, 25
Hemophilia is a _____ clotting disorder.
Blood
About 1 in ____ males are affected.
7,000
Treatments for hemophilia include…
Plasma, gene cloning, Factor VIII drugs
