PNP WK6 Flashcards
What are chromosomes?
- made up of thousands of genes (segments of DNA that contain info about how to synthesise a protein)
- Body contains 23 pairs chromosomes, 22 pairs are autosomes and one pair is sex chromosomes
What is the difference between autosomal and X-linked inheritance?
Autosome: gene being expressed is located on an autosome
X linked: gene being expressed is located on the x chromosome
What is ploidy?
Number of sets of chromosomes in an organism, aneuploidy is abnormal no. of sets
What is a codon?
A sequence of 3 DNA/RNA nucleotides that correspond to a specific amino acid during protein synthesis
What is a point mutation?
replacement of a single base pair with another that can change the identity of an amino acid, create a stop codon, or create a new start codon
What changes can come from a point mutation?
- Turn off a gene so there is no protein
- Stop transcription early and producing a dysfunctional protein
- Prolong transcription so protein cannot function
- Increase function of a protein
- Create interfering protein with normal protein
What are chromosomal disorders?
- Error during meiosis where chromosomes swap portions
- Can cause a translocation (abnormal placement part of chromosome
- Can cause an altered structure (deletion)
What are multifactorial disorders?
- Polygenic or teratogen exposure
- Breast cancer or schizophrenia
What is somatic v gamete gene therapy?
Somatic: normal gene is inserted into somatic cells, cannot be passed on
Gamete: gene is passed on to the children of the person with a hereditary disease as a result of manipulation of the sex
What is organogenesis?
when differentiation and development of the organs are taking place
What is a teratogen?
a chemical, physical, or biological) agent that produces abnormalities during embryonic or fetal development.
What are the different routes of action for teratogens?
- Direct exposure to agent
- Through pregnancy exposure (takes a while)
- As a result of mutagenic effects of a teratogenic agent that occurs before pregnancy
Describe the development of the heart for an embryo
- First to form and develop
- Begins pumping blood on day 21/22
- Develops from cardiogenic area
- Made from cardiogenic cords that form single hollow tube
- Internal septa forms day 28
- AV and semilunar valves develop wk 5-9
Describe the development of the respiratory system for an embryo
- Begins 4 wks into gestation
- Endothermal tissue will form laryngotracheal bud, and trachea will develop proximally
- Alveolar ducts with type I cells, surfectant is produced
- Completed by 36 wks
Describe the development of the renal system for an embryo
- Pronephros, non functional stage
- Mesonephros, transitional kidney formed
- metanephros, development continues until wk 10
- Nephrogenesis, development of ureteric buds, which develop into the ureter, pelvises, calyces, and collecting ducts until wks 32-36
