Vocab Flashcards
Trait
A characteristic caused by genetics or the environment
Chromosomes
long strands of DNA that contain thousands of genes
Genes
part of chromosomes that controls a trait (30,000 in humans)
Allele
different forms of genes
Recessive Allele
only see this traits if 2 are present
Dominant Allele
always shows this trait
Hybrid
has 2 different alleles for the same trait
Purebred
has 2 identical alleles fro the same trait
Probability
the likelihood that an event will occur
Punnett Square
a chart that shows all possible combinations of alleles between 2 organisms
Phenotype
the visibly expressed trait (ie. blue eyes)
Genotype (1)
the allele combination for a trait (ie. Bb or bb)
Homozygous
2 identical alleles (purebred)
Heterozygous
2 different alleles (hybrid)
Codominant Alleles
neither allele is dominant (ie. blood type or spotted dog)
Incomplete Dominance
the dominant alleles mix (ie. Green flower from blue and yellow alleles)
Meiosis
process that creates sex cells with 1 copy of each gene or half of the number of the chromosomes
Cross-Fertilization
a gamete (sex cell) from each parent gives 1 allele for each trait to make a new organism (humans)
Number of Human Chromosomes
23 pairs; 46 chromosomes in total
X and Y
human chromosomes that determine gender
Mutation (pathogenic variant)
when a chromosome is not copied correctly
Carrier
someone how has 1 recessive allele for a trait but doesn’t show it
Pedigree
a chart that tracts a particular trait in a family
Karyotype
a picture of all the chromosomes of a cell
Genome
all the DNA in one cell of an organism
Genotype (2)
an analysis of a genome to determine inherited genes
Gene Therapy
the insertion of a corrected gene into a person to try and correct a problem
Genetic Engineering
transferring a gene from 1 organisms to another to produce a new trait (ie. glowing frog)
Selective Breeding
only mating organisms with desirable traits
Clone
an organism that is genetically identical to the parent organism
Deoxyribonucleic Acid (DNA)
the molecule that is the base of all chromosomes
Four Bases of DNA
Adenine + Thymine, Guanine + Cytosine
Heredity
the passing of traits from parent to offspring
Sex-linked Gene
a gene that is on the Y or X chromosome (hemophilia or colour blindness)
Gregor Mendel
a monk in the 1850’s that studied how plants inherited traits
Crick and Watson
2 scientists who first described the DNA double helix (made a cardboard model of the double helix)
Genetic Disorders
illnesses or disorders caused by an abnormal gene (ie, Downs and Turner Syndrome - wrong # of chromosomes, Recessive Traits - sickle cell anemia, cystic fibrosis)
Inherited Trait
a trait totally controlled by your genes (ie. eye colour)
Environmental Trait
a trait that’s expressed as a combination of your genes and the environment (ie. skin colour)
Epigenetics
how genes are turned off or on by their environment
GM Foods
organisms that have been genetically modified for farmers (GM rice to produce more grain)
Hemoglobin
a protein found in the red blood cells and captures oxygen molecules when blood flows near the lungs then releases when blood flows near starved tissues
Pepsin
a protein structure that breaks down foods in the body
Keratin
a protein structure which strengthens fingernails and claws in organisms
Transcription
The RNA polymerase connects complementary RNA bases to the DNA bases; bases are bonded to make a single strand of mRNa, then it gets sent out of the nucleus into the cytoplasm and attaches to a ribosome
Translation
mRNA and tRNA line up according to thier complementary bases (codons to anticodons) and the tRNA transfers the amino acids. Amino acids are behind and are joined with peptide bonds and later on a protein is made.
Mendel’s Laws
Segregation and Independent Assortment
Segregation
the separation of the 2 alleles
Independent Assortment
when traits don’t affect each other
Polygenetic Traits
traits with more than 2 genotypes (EX: skin tone, height, etc)
Epistasis
when 1 gene depends on another gene for it to be expressed
Deletion
when nucleotide base(s) is missing
Insertion
when nucleotide base(s) is added
De novo change
when new gene variations arise in an egg or sperm bell; new variation can be passed on
