L3: Mendelian Inheritance Flashcards
The first to provide an explanation for hereditary traits in 400 BC
Hippocrates
Said that seeds cause certain traits of the offspring to resemble those of the parents
Hippocrates
Conducted the first systematic studies of genetic crosses
Joseph Kolreuter
Proposed the blending hypothesis of inheritance
Joseph Kolreuter
Occurs when two distinct individuals with different characteristics are bred or crossed
Hybridization
Why did Gregor Mendel choose peas in his studies?
- Easy to grow
- Monoecious
- Self-pollinates but can cross-pollinate
- Has several visible characteristics
- Each characteristic has two common values
Reproductive part of a plant where pollen grains land to stimulate pollen tube formation and for fertilization to take place
Stigma
An opening in the ovule wall where sperm enters to fuse with the egg
Micropyle
A modified petal that covers the reproductive structures
Keel
The general characteristics of an organism
Character
The variant or specific properties of a character
Trait
Occurs when a trait does not vary in appearance from generation to generation
Breeding true
A strain or variety that continues to produce the same characteristic after several generations of self-fertilization
True breeding line
The 7 characters of the pea plant, Pisum sativum
- Seed Shape
- Seed Color
- Flower Color
- Pod Shape
- Pod Color
- Flower Position
- Stem Height
A cross in which only one character is observed
Single-Factor Cross
Also called single-character hybrid, the product of crossing two parents of different variants
Monohybrid
The 2 seed shapes of the pea plant, Pisum sativum
- Round
- Wrinkled
The 2 seed colors of the pea plant, Pisum sativum
- Yellow
- Green
The 2 flower colors of the pea plant, Pisum sativum
- Purple
- White
The 2 pod shapes of the pea plant, Pisum sativum
- Inflated
- Constricted
The 2 pod colors of the pea plant, Pisum sativum
- Yellow
- Green
The 2 flower positions of the pea plant, Pisum sativum
- Arial
- Terminal
The 2 stem heights of the pea plant, Pisum sativum
- Tall
- Dwarf
A theory stating that the genes that govern traits are inherited as discrete units that remain unchanged as they are passed from parent to offspring
Particulate Theory of Inheritance
Defined gene as a unit of heredity that may influence the outcome of an organism’s traits
Wilhelm Johannsen
Different forms of the same gene
Allele
States that the two copies of a gene segregate from each other during transmission from parent to offspring
Mendel’s Law of Segregation
A cross that involves the investigation of two different characters within the same group of individuals
Dihybrid Cross
or
Two-Factor Cross
The 3 lines of scientific inquiry that led to the chromosome theory of inheritance
- Mendel’s studies
- Biochemical basis of heredity
- Microscopic examination of the process of fertilization
Chromosome Theory of Inheritance
The 1st statement
Chromosomes contain the genetic material that is transmitted from parent to offspring and from cell to cell
Chromosome Theory of Inheritance
The 2nd statement
Chromosomes are replicated and passed along, generation after generation, from parent to offspring
Chromosome Theory of Inheritance
The 3rd statement
The nuclei of most eukaryotic cells contain chromosomes that are found in homologous pairs. Gametes contain one set of chromosomes.
Chromosome Theory of Inheritance
The 4th statement
During the formation of haploid cells, different types of chromosomes segregate independently of each other
Chromosome Theory of Inheritance
The 5th statement
Each parent contributes one set of chromosomes to its offspring
Occurs when an offspring receives a combination of alleles that differs from those in its parents
Genetic Recombination
The 2 mechanisms that result to genetic recombination
- Independent Assortment
- Crossing Over
Charts representing family relationships used to study traits and parental crosses
Pedigrees
A disease is said to be […] if a dominant gene not in a sex chromosome causes the disease
Autosomal Dominant
A disease is said to be […] if a homozygous recessive gene not in a sex chromosome causes the disease
Autosomal Recessive
The individual being studied in a pedigree analysis
Proband
or
Index Case
Propositus
Proposita
