| Term | Definition |
|---|
| punnett square | diagram showing the probabilites of the possible outcomes of a genetic cross |
| P generation | parents of a genetic cross; the first two crossed |
| F1 generation | first filial generation; offspring of the P generation |
| F2 generation | seconf filial generation, offspring of the F1 generation |
| incomplete dominance(intermediate inheritance) | neither allele is dominant; heterozygote shows intermediate phenotype; there is the possibility of having a third phenotype (blending). Ex: Red x White=Pink |
| homozygous | having identical alleles for a gene |
| heterozygous | having different alleles for a gene |
| purebred | when the parents and grandparents are of the same breed |
| hybrid | offspring of two different true-breeding varieties |
| dominant | descriptive of the allele in a heterozygous individual that appears to be the only one affecting a trait |
| recessive | descripitve of an allele in a heterozygous individual that does not appear to affect a trait |
| allele | alternative form of a gene |
| gene | a DNA sequence that codes for a protein (polypeptide); mendel called them factors |
| heredity | the passing of traits to offspring |
| genetics | the study of heredity |
| phenotype | observable traits of an organism |
| genotype | genetic makeup of an organism; an organisms combination of alleles |
| Mendel's Laws of Heredity | Law of Indepentdent Assortment and Law of Segregation |
| Law of independent assortment | each allele for a trait segregates into gametes independently of any other alleles, and allele for one trait does not necessarily end up in the same gamete as an allele for a different trait |
| law of segregation | allele pairs (the two alleles for a heritable character) separate during Gametogenesis and end up in different gametes. A sperm or egg carries only one allele of each pair; this law states that allele pairs randomly form pairs at segregation |
| test cross (back cross) | the mating of an individual of unknown genotype but dominant phenotype with a homozygous recessive individual. this cross is used when the genotype is not able to be determined by the information given |
| codominance inheritance pattern | both alleles are dominant, and both phenotypes are present (not blended) Ex: roaning in horses ad cattle |
| incomplete dominance inheritance pattern | neither allele is dominant, heterozygote shows intermediate phenotype (Ex: blending) the F1 hybrids have an intermediate phenotype. the parent phenotypes appear in the F2 generation |
| structure of DNA molecule | DNA structure has sugars and phosphates that form the "backbone". nitrogenous bases are down the center- four different types:adenine, thymine, guanine, and cytosine. DNA molecule consists of a double helix which is an intertwined backbone that forms a helix |
| discovered double helix | watson and crick |
| DNA different from RNA | DNA has deoxyribose sugar, RNA has ribose sugar. DNA has thymine, RNA has uracil; DNA is double stranded, RNA is single stranded |
| function of tRNA(transfer RNA) | "interpreter"; translates nucleic acid language into amino acid language; brings amino acids from cytoplasm to ribosome/mRNA complex; there are 3 tRNA that match an mRNA codon. tRNA tells mRNA which amino acid to pick up from the cytoplasm. Special enzymes "charge" the tRNA; there is one amino acid per tRNA |
| purpose of mRNA | it's complementary to coding strand; the base pairing rules are followed= uracil replaces thymine; when mRNA transcript is formed, it falls off DNA strand when completed |
| DNA replication | process by which DNA makes and exact copy of itself; procces occurs during the S phase of Interphase; cell does for growth, repair, and reproduction |
| end result of replication | two new DNA strand form; strands are complementary copies of parent strands; one strand of parent DNA combines with one strand of new DNA; this is semiconservative replication |
| transcription | process by which DNA makes a single RNA molecule(different form, same message); Only one DNA strand is copied-that strand is a coding or template strand. mRNA is complementary to coding strand. Thymine is replace with Uracil.DNA helix unwinds and exposes the bases; free nucleotides in the cytoplasm base-pair with DNA nucleotides on the coding strand. RNA polymerase creates a bond b/w the DNA and RNA bases. When mRNA transcript is formed, it falls off. DNA rezips to the original double helix. end results in a single stranded RNA molecule. |
| translation | during, codond (set of three bases in mRNA that correspond to triplets in DNA) are decoded into amino acids to make proteins. |
| codon | set of three bases in mRNA that correspond to triplets in DNA |
| anticodon | in tRNA, a triplet of nitrogenous bases that is complementary to a specific codon in mRNA |
| nucleotide | building block (monomer) of nucleic acid polymers |
| gene | a DNA sequence that codes for a protein(polypeptide) |
| adenine | matches with thymine |
| guanine | matches with cytosine |
| in RNA, thymine base is | replaced with uracil |
| proteins(polypeptides) | genes code for these |
| mutations | changes in the DNA sequence of a gene; may be harmful, helpful, silent; two general types: base substitution (not usually harmful) and base insertion or deletion |
| base substitutions mutation | one base (or nucleotide) is replaced by another; changes amino acid, may or may not change the protein; can be silent, minor, or drastic effect. |
| base insertions or deletions mutation | adding or removing one or more bases alters the triplet in DNA and codon reading frame in the mRNA(frameshift mutation); this affects amino acid sequence, there are new amino acids made. this mutation "regroups" bases into different codons. no amino acids(nonsense codon) the protein is not completed or non-working |
| cancer | caused by carcinogens(the mutations that cause this); malignant and benign tumors |
| malignant tumor | tumors that can harm the body |
| benign tumors | tumors that are present in or on the body but have no harmful effects. |
Combine with other sets
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