Lecture 0 Flashcards
Define gene.
the physical units of heredity
What is the chromosome structure of sexually reproducing animals?
eukaryotes
-contained in a nucleus
-long double-stranded DNA, bound by different proteins to form CHROMOSOMES
-chrom. are paired into HOMOLOGS
-have HAPLOID & DIPLOID stages
What is the chromosome structure of bacteria?
-no nucleus
-single, usually circular chromosome
-HAPLOID (one copy)
Besides the nucleus, where else do plants and animals have DNA?
Mitochondria
What happens as a result of MITOSIS?
cells divide to produce genetically IDENTICAL daughter cells
What happens as a result of MEIOSIS?
-cells divide to produce GAMETES (sperm & egg)
-daughter cells are haploid (one chromosome from each homolog)
Define genotype.
the genetic constitution of an organism aka the sequence
Define phenotype.
the observable traits of an organism
Define allele.
alternate forms of a gene, that can alter the product of a gene
Are alleles part of genotype or phenotype?
Genotype
What is the central dogma?
DNA –(Transcription) –> RNA –(Translation)–> Protein
How does DNA’s structure suggest a mechanism for DNA replication?
-Double helix: each strand acts as a template strand allowing for 2 new strands from the OG helix (semiconservative replication)
-Phosphate-sugar backbone: provides stabile structure for new base pairs to be added
-Complementary base pairs: one strand can act as a template strand
IN PROGRESS What is the structure of DNA?
Phosphate-sugar backbone nucleotides are positioned in the interior of the helix and are hydrophobic
-complimentary base pairing of the bases. Guanine+Cytosine= 3 hydrogen bonds. Adenine + Thymine= 2 hydrogen bonds. Antiparallel structure suggests replication occurs from opposite directions in a DNA molecule.
What is the purpose of gel electrophoresis?
To separate different nucleic acid fragments from one another and identify bases in a DNA sequence.
What is the one molecular characteristic that DNA or RNA molecules enabling separation in gel electrophoresis?
Charge
