AB 4 Flashcards
(16 cards)
What is Incomplete Dominance?
A genetic scenario where alleles partially influence the phenotype of the offspring, resulting in an intermediate phenotype between parental phenotypes.
Example: Red flower x White flower produces Pink flowers.
What is Codominance?
A genetic scenario where both alleles are independently and equally expressed in the phenotype.
Example: A red cow and a white bull produce a roan calf.
What are the methods used in Human Genetics studies?
- Twin studies
- Biochemical research
- Statistics
- Family tree analysis
- Microscopic studies (karyograms)
These methods help in understanding inheritance patterns in humans.
What is a mutation?
A change within a nucleic acid (DNA/RNA) that can lead to different proteins being produced.
Mutations can be silent, neutral, or result in different amino acids.
What is a gene mutation?
A change in a gene that can occur through substitution, insertion, or deletion of base pairs.
Types of gene mutations include: * Substitution * Insertion * Deletion.
What is a frameshift mutation?
A mutation caused by the insertion or deletion of a base, which shifts the reading frame of the genetic code.
This can lead to different amino acids being coded.
What are chromosome mutations?
Changes in chromosomes that can include duplication, deletion, inversion, or translocation.
Typically affects more than one gene.
What is genome mutation?
A change in the number of chromosomes, which can be increased or reduced.
This can lead to changes in phenotype or bodily function.
What are antigens?
Substances on the surface of red blood cells that can trigger an immune response.
Example: Blood group antigens.
What are antibodies?
Proteins in blood plasma that recognize and bind to specific antigens.
Example: Anti-A and Anti-B antibodies in blood plasma.
What is the result of mixing blood from two individuals?
It can lead to blood clumping, also known as agglutination.
This is due to the interaction between antigens and antibodies.
What is the significance of A and B alleles in blood groups?
A and B are co-dominant alleles, while O is recessive.
Individuals can be homozygous or heterozygous for blood groups.
What is Preimplantation Genetic Diagnosis (PGD)?
A method used to diagnose genetic disorders before implantation during in vitro fertilization.
It helps in selecting embryos free from specific genetic diseases.
What is non-disjunction in meiosis?
An error during meiosis I where chromosomes fail to separate properly.
This can lead to conditions like Down syndrome.
What is Monosomy?
A genetic condition where there is only one copy of a chromosome instead of the usual pair.
Example: Turner syndrome (X0).
True or False: Mutations are random and not all genes are ‘turned on’ at a given time.
True.
Mutations can occur in any organism and not all genes are expressed simultaneously.
