Unit 5: Genetics and Biotechnology Flashcards
Allele
Alternate forms of a gene ex T or t
Amniocentesis
a technique used to sample amniotic fluid (which contains fetal cells) to determine if a fetus has a genetic disorder
Autosome
a non-sex chromosome #1-44
Bacterial/Genetic Transformation
process of inserting DNA from one species into another creating a transgenic organism
Biotechnology
branch of biology that involves modifying the genes of organisms to improve human life; also called genetic engineering, molecular biology, and recombinant DNA technology
Cloning
process of making genetically-identical copies of genes or entire organisms
Codominance
complex pattern of inheritance in which both alleles are expressed equally in the phenotype
Color Blindness (Define and Cause)
sex-linked trait in which sufferers fail to distinguish between certain colors–usually red and green
Crossing Over
process that occurs in meiosis in which homologous chromosomes overlap and exchange pieces creating unique sperm/egg cells
Cystic Fibrosis (Define and Cause)
autosomal recessive disease characterized by a thick accumulation of mucus in the lungs and digestive tract
Diabetes (Define and Cause)
a disease caused by a failure of the body to produce insulin (type I) or the development of insulin resistance over time (type II)
Dominant
an allele or trait that is always expressed, is always the uppercase letter
DNA Fingerprint
a pattern of bands in a gel created during electrophoresis that is unique for all of the members of a sexually-reproducing population
Down Syndrome/Trisomy 21 (Define and Cause)
individuals that have 3 copies of chromosome #21
Fertilization
process in which a sperm cell unites with an egg cell
Gel Electrophoresis
process that uses an electrical current to separate DNA fragments by size creating a unique banding pattern in a gel called a DNA fingerprint; also called DNA fingerprinting
Gene
A segment of DNA that codes for a protein/trait
Gene Therapy
replacing defective genes with normal ones to cure disease
GMO
genetically modified organism whose genome has been altered artificially through genetic engineering
Genetics
the study of heredity
Genome
all the genes found in a species
Genotype
the combination of alleles for a trait(s) ex Tt, tt, or TT
Hemophilia (Define and Cause)
sex-linked disease caused the lack of a blood clotting protein; sufferers can bleed to death from a simple cut/bruise
Heterozygous
an organism has a dominant allele paired with a recessive allele; ex. Tt
Homozygous Chromosomes
a pair of chromosomes that are the same size and have genes arranged in the same order; one comes from mom and one from dad
Homozygous
an organism has the same two alleles for a particular trait; ex. TT or tt
Human Genome Project (Define and Purpose)
was established in 1990 to sequence the 3 billion base pairs of human DNA (finished in 2001) and to map our 35,000 genes
Huntington’s Disease (Define and Cause)
autosomal dominant disease characterized by a late onset (around age 35) and breakdown of the central nervous system; death by 45
Incomplete Dominance
complex pattern of inheritance in which neither allele is dominant over the other resulting in an intermediate/blended phenotype
Karyotype
a picture of a fetus’s chromosomes arranged in homologous pairs which can be used to determine sex and if genetic abnormalities are present
Meiosis
a form of cell division that makes four genetically-different haploid gametes
Multiple Alleles
complex pattern of inheritance governing human blood types (A, B, AB, O), in which there are more than two alleles for a trait
Nondisjunction
the failure of chromosomes to separate properly during meiosis leading to genetic diseases like Down Syndrome, is very uncommon
Pedigree
a chart showing the genetic relationships amongst the members of a family; can show traits/diseases
Phenotype
the physical expression of the genotype; ex. brown eyes
Plasmid
tiny rings of DNA found in bacteria located outside of their large circular chromosome, that often contain genes for antibiotic resistance and that we use to carry human genes in biotech, like the gene for insulin
Polygenic Inheritance
complex pattern of inheritance in which traits with a broad range of phenotypes are controlled by more than one gene; examples include human height, skin color, weight, eye color, and hair color
Punnett Square
a diagram that is used to show the probability of outcomes from a genetic cross
Recessive
an allele or trait that is only expressed when not in the presence of a dominant one
Restriction Enzyme
proteins that cut DNA into fragments; “molecular scissors”
Severe Combined Immunodeficiency (Define and Cause)
a sex-linked recessive disorder in which the patient lacks an immune system; has been successfully treated in some instances with gene therapy; AKA bubble boy syndrome
Sex Chromosome
chromosomes that determine sex; the X and Y chromosomes
Sex-Linked Traits
caused by genes on the X chromosome and are most often passed from mother to son
Sickle Cell Anemia (Define and Cause)
disease that is caused by a mutation in DNA resulting in defective hemoglobin and leading to crescent-shaped red blood cells; carriers are immune to malaria
Transgenic Organism
A genetically-modified organism (GMO) that contains foreign DNA (DNA from another species); ex. a glowing mouse or a frost-resistant strawberry plant
Variation
Any difference between individuals of the same species.
Zygote
a fertilized egg cell
