2 Flashcards
Transcription
Transcription is the process of a gene’s DNA sequence being copied to make an RNA molecule. INITIATION begins when RNA polymerase binds to the promoter, which signals the DNA to unwind and prepares it for mRNA synthesis. ELONGATION is when RNA polymerase is added to the template strand in the 3’ to 5’ region. TERMINATION is when the transcribing RNA polymerase releases DNA template and nascent RNA and disassembly begins.
Translation
Translation is the process that creates proteins. INITIATION is when the small and large ribosomal subunits bind to mRNA. Then, tRNA binds to the start codon of mRNA. ELONGATION is when the amino acid sequences are extended and the formation of the amino acid chain is created. TERMINATION is when a stop codon binds to the A-site and disassembly begins.
Gene
A gene is a short stretch of DNA that codes for a characteristic.
Genotype
A genotype is the alleles an individual carries within their genes.
Sickle cell anemia
Sickle cell anemia is caused by one single-base substitution mutation (GLU to VAL). The new shape of the sickled red blood cells causes them to clump together easier and clog blood vessels.
X-linked versus Y-linked genes
X-linked genes determine sex, while Y-linked genes control characteristics unrelated to sex.
Haploid versus diploid cells
Haploid cells have one copy of each chromosome (non-homologous, I I I), whereas diploid cells have two copies of each chromosome (homologous, II II II).
Amniocentesis
Amniocentesis is a prenatal test that takes amniotic fluid from the uterus, around an individual’s baby, to test if the baby has certain health conditions.
Chorionic villus sampling
Chorionic villus sampling is a prenatal test that takes a sample of tissue from the placenta to test if the individual’s baby has any genetic or chromosomal conditions.
Process of transpiration
Transpiration is a passive process involving water adhering to the cell wall and creating a film of water on the surface of cells, which allows water to evaporate from the cell wall into the air.
What are the 3 requirements for germination?
The 3 requirements for germination are water, oxygen, and temperature.
Discontinuous variations versus continuous variations
Discontinuous variations are influenced by one gene or a few genes and not influenced by the environment (ex: human blood type). Continuous variations are controlled by many genes and are influenced by the environment (ex: human height).
Homologous structure versus analogous structure
Homologous structure refers to 2 things being similar in structure and evolutionary origin, but not function (ex: human arm & dolphin flipper). Analogous structure refers to 2 things being similar in function, but not structure or origin (orca fin & shark fin).
Speciation, allopatric speciation, and sympatric speciation
Speciation occurs when 2 species become genetically different enough they can no longer interbreed. Allopatric speciation is when populations become geographically separated and establish reproductive isolation. Sympatric speciation is when a population forms a new species within the same area as the parent species.
Cane toads
Cane toads are an example of an alien/invasive species. They mass populated Australia due to the absence of natural predators, its rapid rate of reproduction, and the lethal toxin it produces.
