BIO 2 FINALS

• Genes


  Basic physical and functional unit of heredity, made up of DNA
• Alleles


  Variant form of a gene
• Homozygous


  2 alleles are similar
• Heterozygous


  2 alleles are different
• Phenotype


  Expression of the code or the genotype
• Genotype


  Genetic code of individual
• Punnett Square


  Square diagram used to predict the genotypes of a particular cross or breeding experiments
• Reginald C. Punnett - based on the name of the punnett square
• Monohybrid


  Cross happening in the F1 generation offspring of parents differing in one trait only
• Dihybrid


  Cross happening to F1 generation offspring differing in two traits
• Gregor Mendel


  Father of Modern Genetics, Austrian monk and teacher who experimented with garden peas
• Garden Peas


  • Contains pollen and pistils, producing through sexual reproduction, complete flowers with both female and male parts
• Incomplete Dominance


  Two alleles blend their characteristics with a trait, neither one is dominant
• Codominance


  Existing in both, some alleles are present but not blended, neither allele is dominant or recessive
• Nucleotide (Base Pairing)


  Building blocks of DNA, connected through hydrogen bonds
• 4 Main Nucleotides

  • Thymine
  • Adenine
  • Cytosine
  • Guanine
• DNA consists of 300 to 1 million nucleotides
• Gene


  Basic unit of heredity, where traits can be found, needed to produce offspring and transmitted to next generation
• DNA (Deoxyribonucleic Acid)


  Long chain of nucleotides, genetic material that contains information about a person, makes up chromosomes
• RNA (Ribonucleic Acid)


  Carrying genetic information, single stranded sugar phosphate with single set of nucleotides (Uracil, Adenine, Cytosine, Guanine)
• Histones


  Basic proteins found in eukaryotic cells, wrap DNA, proteins that DNA is tightly coiled around
• Chromatin


  Coil genetic material, package the long DNA nucleotide into more compact and dense structures
• Chromatid


  One of the two identical halves of a duplicated chromosome, also known as sister chromatids, connected by the centromere
• Homologous Chromosomes


  Two pieces of DNA within a diploid organism which carry the same genes, one from each parental source
• Chromosomes


  Ribbon-like structure of DNA, most compact, threadlike structure of nucleic acids carrying genetic information
• We have 23 pairs of chromosomes
• Genome


  Full set of DNA made of chromosomes
• We need to compress DNA to form chromosomes due to cell division, and all chromosomes will be duplicated during interphase
• We can count chromosomes by looking at the centromere, not all chromosomes are X-shaped, DNA in prokaryotic cells are usually circular
• Autosomal Chromosomes


  1st and 22nd chromosomes, have genes related to eye color, height, hair structure, and traits
• Sex Chromosomes


  The 23rd chromosome, have genes that distinguish biological sex (xy=boy, xx=girl)
• The sex will depend on the father, 50-51% probability of having a boy or girl depending on whether the sperm is x or y
• Karyotype


  Picture or image of all of a person's chromosomes, used by doctors to detect abnormalities
• Things to consider in Karyotyping


  • Number of chromosomes, sizes of chromosomes, shapes or structure of chromosomes
• Trisomy 21 (Down Syndrome)


  Extra full or partial copy of chromosome 21, causes mild to moderate cognitive impairment, language delay, and memory issues
• Common features of Trisomy 21


  • Flattened face, small head, short neck, protruding tongue, upward slanting eye lids, short fingers and small hands and feet, short height
• 45 X (Turner Syndrome)


  45 chromosomes instead of 46, partially or completely missing chromosomes, only happens in females
• Signs of 45 X


  • Wide or weblike neck, low set ears, broad chest with widely spaced nipples, swelling of hands and feet, slowed growth, failure to begin sexual changes in puberty, early end to menstrual cycles