Study guide 6 (exam2) Flashcards
What are steroid hormones?
Pass through membrane, bind receptors, alter gene transcription
What are peptide hormones?
Bind to surface receptors, trigger enzyme chain
What are nucleotides?
Building blocks of DNA
What is a double helix?
two nucleotide strands held together by hydrogen bonds
Who is Rosalind Franklin?
Rosalind Franklin made an X-ray diffraction photograph.
Who is Maurice Wilkins?
Maurice Wilkins’ laboratory was used for the X-ray photograph.
Who are Francis Crick and James Watson?
Francis Crick and James Watson deduced the structure of DNA; double helix.
What is semiconservative replication?
each DNA strand makes a new one
What is DNA polymerase III?
adds complementary nucleotides to the exposed DNA strand
What is the Central Dogma?
DNA —> RNA —> Protein.
What is gene expression?
DNA controls protein production
What is transcription?
RNA polymerase makes an mRNA copy of a gene
What is RNA polymerase?
Enzyme responsible for transcription
What is a promoter?
RNA binding site
What is mRNA?
mRNA carries gene code to make a polypeptide
What is translation?
Converts gene nucleotides into amino acid sequence
What are ribosomes?
Cellular structures responsible for translation.
What are proteins?
made during translation
What is a START codon?
AUG (begin protein synthesis)
What is ribosomes composition?
Protein and RNA
What is tRNA?
tRNA is transfer RNA, a type of RNA molecule.
What is an anticodon?
Three-nucleotide sequence of a tRNA molecule; decides which amino acid gets to attach to a tRNA.
What is an exon?
DNA part that is transcribed and translated into protein
What is an intron?
DNA part transcribed, but removed before translation
What is a primary RNA transcript?
Gene with exons and introns
What are the 5’ cap and 3’ poly-A tail?
protect RNA transcript from degradation
What is alternative splicing?
Removing introns —> Joins two exons together
What are the steps of gene expression?
- Transcription
- RNA processing
- mRNA to ribosome
- tRNA matches anticodons
- tRNA brings amino acids
- mRNA → polypeptide
What is the translation process?
- tRNA binds at P site
- New tRNA enters at A site
- Codon-anticodon match
- Ribosome moves, transferring amino acid
- tRNA exits at E site
What is the genetic code?
Translate mRNA codon to appropriate amino acid
What is a codon?
(basic unit of genetic code) 3-nucleotide sequence that codes for an amino acid/polypeptide termination
What are amino acids?
Building blocks of proteins, specified by codons.
