History of Genetics
What is heredity?
The passing on of characteristics genetically from one generation to another.
What are the 4 bases found in DNA?
G, T, A, C
What do we call the units of inheritance that cause inherited traits?
Genes
What is the difference between homozygous and heterozygous genotypes?
Homozygous have two of the same allele, heterozygous have two different alleles.
How are males and females depicted in a pedigree?
Males: Squares
Females: Circles
What does DNA stand for?
Deoxyribonucleic Acid
What are the two alternating components that make up the DNA backbone?
Deoxyribose sugar and phosphate groups
What was one misconception people believed about heredity before Mendel’s experiments?
Possible Answers:
- One parent contributed most to an offspring’s inherited features.
- Blended inheritance, where parental traits become mixed and forever changed in the offspring.
What is the difference between monohybrid and dihybrid crosses?
A monohybrid cross tracks the inheritance of a single genetic trait, while a dihybrid cross tracks two separate genetic traits simultaneously
What does it mean for an individual to be “affected”?
Someone who expresses the phenotype of the trait being studied, meaning they show the disease or characteristic of interest.
What evidence do we have that all organisms share a common ancestor?
That all living things are made up of nucleotides.
What are the 3 components of a nucleotide?
A nitrogenous base, a sugar (either ribose or deoxyribose), and a phosphate group
What was Mendel the first to do?
He explained why traits could appear, disappear, and later reappear across generations.
How many potential offspring are produced in a dihybrid cross?
16
What is a “carrier”?
A heterozygous individual that does not display a recessive phenotype, but is able to pass on the recessive allele.
What is the entire collection of chromosomes in each cell of an organism called?
What are the 3 differences between DNA and RNA?
DNA: Double-stranded, A bonds with T, deoxyribose sugar
RNA: Single-stranded, A bonds with U, ribose sugar
Name 2 reasons Mendel chose peas for his experiments.
Possible Answers:
Peas grow well in Brunn, and it is easy to prevent self-fertilization and instead cross-fertilize.
They also produce a large number of individuals in a short growing season.
Peas have many observable traits, making it easy to track traits from generation to generation.
It was easy to track large amounts of peas from multiple generations at the same time.
What do we call alternate forms of a gene?
Alleles
How do we identify individual people in a pedigree?
Generation (Roman Numerals) and Number to identify the individual from left-right. EX: II-2
What is the difference between genetics and genomics?
Genetics focuses on individual genes and heredity, while genomics studies an organism's entire genome, which includes all of its genes, how they interact with each other, and the influence of the environment.
Proteins are made up of what?
Amino Acids
How do we refer to each generation in a cross? (the initial parents, then the first generation of offspring, then the second generation of offspring, etc.)
P generation
F1 generation
F2 generation
What does the Law of Segregation state?
During the formation of gametes, the two alleles for each trait separate from each other so that each gamete carries only one allele.
Horizontal patterns in a pedigree indicate what?
Recessive traits