Lesson 1: Genetics and Heredity Flashcards
meow
It is the study of genes.
Genetics
How traits, characteristics, are passed on from generation to generation.
Inheritance
It is found inside the nucleus of a cell
Genetic material
He is the father of genetics
Gregor Mendel
What was the primary objective of Gregor Mendel’s experiments with pea plants?
To understand the fundamental principles of how traits are passed down from parents to offspring.
Parents pass on to their offspring separate and distinct factors that are responsible for inherited traits.
Particulate Hypothesis of Inheritance
Why did Gregor Mendel choose the Garden Pea?
- Because they are available in many varieties.
- It gave him strict control over which plants mated.
- The pea traits are distinct and were clearly contrasting.
HOW DID MENDEL ENSURE THE PURITY OF HIS PEA PLANT LINES BEFORE CONDUCTING HIS EXPERIMENTS, AND WHY WAS THIS IMPORTANT FOR HIS RESEARCH?
By practicing self-pollination.
Pea plants reproduce sexually, which means that they produce male and female sex cells, called _______
Gametes.
When male gamete unites with female gamete it is called ___________
Fertilization.
It is a genetic cross that involves a single pair of genes that is responsible for one trait.
Monohybrid cross.
It is the offspring of parents that have different forms of traits, such as purple color and white color.
Hybrid
It is a segment of DNA that contains the instructions for building a specific protein or performing a particular function within an organism.
Gene.
It is a distinct form of a gene
Allele
An individual’s combination of alleles is known as their ________.
Genotype.
What are Mendel’s conclusions?
- The Law of Dominance
- The Law of Segregation
- The Law of Independent Assortment
Can mask or dominate the other factor and is displayed most often.
Dominant
It is the factor that can be covered up; is displayed less often.
Recessive.
Inherits two similar alleles from the parents for a particular gene (Ex. TT, tt)
Homozygous.
Inherits two different alleles from the parents for a particular gene (Ex. Tt)
Heterozygous.
It is a cross between two pure organisms in order to study the inheritance of two pairs of contrasting characters.
Dihybrid cross.
It shows the possible combinations of alleles from parents when they are crossed (fertilization).
Used to predict the genotype and phenotype of any offspring.
Punnett squares.
It is an organism’s genetic information.
Genotype.
It is the set of observable physical traits.
Phenotype.
It is a genetic cross between an individual with a dominant phenotype (but unknown genotype) and a homozygous recessive individual.
Test cross.
What is the purpose of a test cross?
To determine the genotype of the dominant individual by observing the phenotypes of their offspring.
In a _______ ______, we are dealing with three different traits that are each located on different chromosomes. Each parent in the cross has two alleles for each of these traits, one inherited from the mother and one from the father.
Trihybrid cross.
Also known as Mendel’s first law of inheritance, states that when two different alleles (versions of a gene) are present in an individual’s DNA, the dominant allele will be expressed over the recessive allele.
The Law of Dominance.
It is a fundamental principle in genetics that states that an individual’s two copies of a gene (called alleles) separate from each other during the formation of sex cells such as sperm and eggs. This means that each gamete receives only one copy of each gene, which is randomly selected from the two copies present in the parent.
The Law of Segregation
It is a principle in genetics that states that the inheritance of one gene does not affect the inheritance of another gene. This means that genes are randomly sorted and passed down to offspring independently of each other, resulting in unique combinations of traits.
The Law of Independent Assortment.
