Flashcards in Genetics Deck (110):
Used to describe a part of the DNA molecule that contains the information needed to code for the types of protein and enzymes
Study of heredity
What are the four nitrogenous bases of DNA?
Adenine, cytosine, thymine, guanine
What does DNA do?
Directs protein synthesis
What are the two types of DNA?
Nuclear and mitochondrial
Accumulation of genes from gametes of two parents
Matrilineal inheritance-descent through the female line
Involved in the actual synthesis of cellular enzymes and proteins
Copies the meaningful strand of DNA and carries the message from nucleus to cytoplasm
Copying the meaningful strand of RNA
Selects the appropriate amino acids and carries them to ribosomal RNA
Forms 60% of the ribosome and assembles the proteins
Assembling the proteins
Inherited alteration of genetic material
What do mutations result from?
Substitution, loss or addition, or rearrangement of base pairs
Where might mutations arise?
Somatic or germ cells
Intracellular structures where genetic information is organized, stored, and retrieved
Examples of haploid cells
Ovum and sperm
Examples of diploid cells
Formation of 2 daughter nuclei containing the identical complements of the number of chromosomes characteristic of the somatic cells
Replication of germ cells that occurs only in gamete producing cells of the ovaries and testes
What are the four phases of the cell cycle?
Interphase, prophase, anaphase, and telephase
Actual genetic information
How the genes are expressed
Multiple genes contribute to the trait
Multiple alleles affect outcome and includes environmental effects
Variants in a particular gene
If both alleles are identical
If alleles are different
One allele is more powerful than the other
What pair of chromosomes determine sex?
What do females contribute?
What do males contribute?
When will a recessive allele be evident?
If both alleles are recessive
What are most hereditary disorders caused by?
If an hereditary disorder is sex-linked what is it passed through?
Who is affected in autosomal dominant?
Male and females equally
If one parent is affected in autosomal dominant what is the chance of offspring being affected?
If both parents are affected in autosomal dominant what is the chance of offspring being affected?
What is an example of an autosomal dominant disorder?
Causes connective tissue disease
What is a physical trait of Marfan Syndrome?
Long tall bodies
Who is affected in autosomal recessive?
Male and females equally
If both parents are carriers in autosomal recessive what is the chance of offspring being affected?
If both parents are effected in autosomal recessive what chance will the offspring have?
If one parent is affected and other is not a carrier in autosomal recessive
Children will be unaffected but carriers
If one parent is affected and the other is a carrier in autosomal recessive
Each child will have 50% chance of being affected
Most common inherited clotting disease that is the least severe
Von Willebrand disease
Deficiency or defect of a blood clotting protein that helps platelets aggregate
Von Willebrand disease
Inherited autosomal recessive gene that causes increasing levels of phenylanine hat leads to brain damage
Lipid pigments accumate because of an enzyme deficiency that destroys CNS cells and is usually fatal by age five
Most common fatal genetic disease
Results from mutations that do not allow proteins to function correctly
What is lacking in cystic fibrosis?
Does cystic fibrosis have a cure?
What are some symptoms of CF?
Viscous mucus secretions, respiratory problems, GI problems, and reproductive problems
What are some physical appearance changes with CF?
Barrel chest, distended abdomen, and clubbing
What are diagnostic tests for CF?
Positive sweat test, CXR, stool, DNA testing
What are ways to manage CF?
Control lung infections, remove secretions, prevent blockages in intestines, provide nutrition, and prevent dehydration
What is the inheritance of sickle cell anemia?
How many African Americans carry abnormal genes for sickle cell?
How many black children have sickle cell anemia?
RBCs look sickled which decreases oxygen carrying and may cause clots
Sickle cell anemia
Inheritance of genes associated with the X chromosome
Who do males transmit X to?
Daughter not sons
Who do females transmit X to?
Daughter and son
Who do x-linked recessive disorders affect?
Males with unaffected parents
X-linked recessive male disorders
All daughters are carriers and males are unaffected
What is an example of and x-linked recessive disorder?
How do x-linked dominant disorder affect males?
Who is hemophilia most common in?
Males and is rare in females
Deficiency of factor 8
Deficiency of factor 9
Hemophilia B (Christmas disease)
What are some symptoms of hemophilia?
Painful swollen joints, limited ROM, spontaneous bleeding, shock like symptoms
What are the diagnostics for hemophilia?
Coagulation factor, aPTT prolonged, platelets, low factor 8 or 9
Treatments for hemophilia A
Clotting factors or antihemolitic factors
Treatment for hemophilia B
Factor 7 or purified factor 9, analgesics, and safety measures
Linked to both genes and environment
Multifactorial inheritance disorders
Examples of multifactorial inheritance disorders
Cleft lip/palate or diabetes
A somatic cell that does not containa multiple of 23 chromosomes
Three copies of one chromosome
What is usually seen with aneuploidies?
How many births does down syndrome effect?
Risk for down syndrome child at age 20
Risk for down syndrome child at age 49
Chromosome 21 has three copies instead of two
What is the mortality rate like in down syndrome children?
What are other problems that are associated with down syndrome?
Heart problems, club foot, cleft palate of lip, colon enlargement, wide space between 1st and 2nd toes, and dental problems
Testing for down syndrome
Prenatal ultrasound, AFP, amniocentesis
When do you do AFP test?
Disorder that is present at birth
When do congenital disorders occur?
When developing embryo is subjected to adverse environmental conditions
When is the period of vulnerability with congenital disorders?
What can happen when babies are born to cocaine addicted mothers?
Baby can be born addicted
Why is folic acid deficiency dangerous?
Folic acid helps form RBCs and produce DNA
Adenine + Guanine
Thymine + Cytosine
How many chromosomes in the haploid nucleus?
How many pairs in the diploid nucleus?
What are some main SE of Von Willebrand disease?
Prolonged nosebleeds, heavy periods, prolonged bleeding after surgery
What kind of diet so PKU people need?
Limited phenylalanine often found in proteins
What organs are most often effected by sickle cell?
Kidney and spleen
Caused by lack of clotting factor 11
How is hemophilia diagnosed?
Measuring the level of factor activity in the blood
Should people with hemophilia avoid aspirin?
Yes because it effects clotting