Final Exam - Mutations Flashcards
teratogen
chemicals or other agents that cause birth defects
-examples include drugs, viruses, protozoans, social activities, lack of nutrients
transition
purine is substituted for a different purine or pyrimidine is substituted for another pyramidine
transversion
purine substituted for a a pyrimidine
missense
wrong aa is inserted into a chain
- ex glu to val
- sickle cell anemia
- dwarfism
sense
stop codon changed to aa reading codon
-thalaseemias
nonsense
aa readin codon is changed to a stop codon
-thalassemias, marfan syndrome
silent
same aa is brought into chain by a different codon
frameshift mutation
additon or deletion of bases can change the reading codons downstream
dimer
between two adjacent pyrimidines caused by UV light
excision repair
error in process to remove thymine dimers causes xeroderma pigmentosum
photoreactivation enzyme
enzyme cuts the dimer so it doesnt cause a problem
neoplasia
abnormal cellular growth
carcinoma
ectoderm/endoderm so skin, brain, colon
leukemia/lymphoma
immune system
- too many white blood cells
- lymph system
sarcoma
-mesoderm which includes the bone, fat, muscles, and connective tissue
constitutional
inherited mutations
sporadic
spontaneous so no mutation in the genome, new mutation must occur
retrovirus
enters body cell which disrupts the DNA sequence
-example HIV and HPV,
proto-oncogene
-a normal cell divison regulating gene mutates into an oncogene which causes uncontrolled cell growth
oncogene
causes uncontrolled cell growth
-mutated proto-oncogene
anti-oncogene
tumor supressor gene can mutate or is lost from the cells genome
repair gene
error in DNA repairs which can lead to cancer
adenoma
non cancerous tumor that can affect organs
-formed by muliple polyps
Breast Cancer
-error in DNA repair gene
-BRCA 1- inherited error, closely linked to ovarian and prostate cancer
BRCA2- less frequent that BRCA 1, dna gene repair error in G1
colon/rectal cancer
- FAP - Familial adnomatous polypsosis which is the homozygous recessive state=no polyps. Adenoma, cause is a tumor supressor gene
- HNPCC-hereditary nonpolyposis colon cancer which involves autosomal dominant repair genes
Li Fraumeni syndrome
- dominant tumor supressor p53 gene is deleted
- loss is associated with many sporadic cancers
- normal p53’s protein helps regulate cyclin’s activity and controls the cell cycle
lymphocytes
white blood cells that are formed in the bone marrow as a response to foreign antigens
T-cells
- processed in the thymus gland involved in cell mediated immunity
- helper- alert about foreign antigen
- cytotoxic (killer)- attack other cells directly
- memory- encounter same foreign protein which stimulates the immune system
B cells
active and involved in antibody mediated immunity
- memory -remember foreign antigens
- plasma- produce antibodies
plasma cells
make antibodies which are y shaped proteins that consist of light and heavy chains with constant and variable regions
clonal selection
antibody and antigen match
immunoglobulins
antibodies produced by plasma cells and they recognize and bind to antigens
Ig G
found in blood plasma that can cross the placenta and the Rh factor incompatibility can lead to hemolytic disease by the bilirubin
Ig A
found in body secretions which protect the body openings in skin and cavity linings
Ig M
found in blood plasma but cannot cross the placenta
-ex ABO RBC surface proteins-universal donor and reciever
Ig E
causes allergic reactions so a hypersensitive immune system
hemolytic diease
when blood types of mother and baby are incompatible, Rh incompatability
autoimmune dieases
when the body forgets what belongs to itself so it attacks itself
ex. insulin dependent diabetes, rheumatoid arthritis, lupus, multiple sclerosis, and scleroderma
major histocompatibility complex
transplants require HLA matching which is difficult because of numerous alleles
immune dieases
- SCID- severe combined immunodeficiency, no B or T cells
- XLA - agammaglobulinemia-defective or no B cells produces
- HIV-caused by a retrovirus and destroys helper t cells
