Introduction to Genetics Flashcards
is the general process by which traits controlled by genes are transmitted through gametes from generation to generation
Transmission genetics
explains how genetic information is stored and expressed. This discovery is the foundation of molecular genetics.
The Watson–Crick model of DNA structure
a molecular complex found in bacteria that has the potential to revolutionize our ability to
rewrite the DNA sequence of genes from any organism
CRISPR-Cas
it represents the ultimate tool in genetic technology
CRISPR-Cas
Other systems have been developed aside from the CRISPR-Cas
zinc-finger nucleases (ZFNs) & transcription activator-like effector nucleases (TALENs)
CRISPR means
(clustered regularly interspersed short palindromic repeats)
How does CRISPR work
designates an RNA molecule, which in the laboratory can be synthesized to match any DNA sequence of choice
CRISPR RNA has two ends
- Recognizes and binds to a matching DNA sequence in the gene of interest
- The other binds to a CRISPR-associated
(Cas) nuclease, or DNA-cutting enzyme
What is the most commonly used Cas nuclease
Cas9
CRISPR-Cas systems have already been used to repair mutations in cells derived from individuals with several genetic disorders, including…
cystic fibrosis
Huntington disease
beta-thalassemia
sickle cell disease
muscular dystrophy
X-linked retinitis pigmentosa
For example, one research group was able to use this system to spread genes that prevent mosquitoes from carrying the parasite that causes malaria. Other researchers have proposed using CRISPR-Cas9 to engineer laboratory-grown human blood vessels and organs that do not express proteins that cause rejection of transplanted tissues and organs. The method has also been used to create disease-resistant strains of wheat and rice.
Between 8000 and 1000 b.c., horses, camels, oxen, and wolves were domesticated, and selective breeding of these species soon followed. Cultivation of many plants, including maize, wheat, rice, and the date palm, began around 5000 b.c. Such evidence documents our ancestors’ successful attempts to manipulate the genetic composition of species
The ————————-argued that active “humors” in various parts of the body served as the bearers of hereditary traits
The Hippocratic treatise “On the Seed”
He proposed that the male semen contained a “vital heat” with the capacity to produce offspring of the same “form” (i.e., basic structure and capacities) as the parent
He believed that this heat cooked and shaped the menstrual blood produced by the female, which was the “physical substance” that gave rise to an offspring
The embryo developed not because it already contained the parts of an adult in miniature form (as some Hippocratics had thought) but because of the shaping power of the vital heat
Aristotle
What is epigenesis?
an organism develops from the fertilized egg by a succession of developmental events that eventually transform the egg into an adult
What is the theory of preformation?
fertilized egg contains a complete miniature adult, called a homunculus
State the cell theory
all organisms are composed of basic structural units called cells, which are derived from pre-existing cells
What is the name of the published work of Charles Darwin
The Origin of Species, in 1859
What was the name of the ship boarded by Charles Darwin in his expedition
HMS Beagle (1831-1836)
Explain natural selection
natural selection is based on the observation that populations tend to contain more offspring than the environment can support, leading to a struggle for survival among individuals. Those individuals with heritable traits that allow them to adapt to their environment are better able to survive and reproduce than those with less adaptive traits.
heredity and development were dependent on genetic information residing in genes contained in chromosomes, which were then contributed to each individual by gametes—the so-called
chromosomal theory of inheritance
in most eukaryotes, members of each species have a characteristic number of chromosomes called the…
diploid number (2n)
Chromosomes in diploid cells exist in pairs, called…
homologous chromosomes
A colorized image of the human male chromosome set. Arranged in this way, the set is called a —–
karyotype
states that inherited traits are controlled by genes residing on chromosomes faithfully transmitted through gametes, maintaining genetic continuity from generation to generation.
chromosome theory of inheritance
any heritable change in the DNA sequence and are the source of all genetic variation
Mutation
defined as alternative forms of a gene
Alleles
The set of alleles for a given trait carried by an organism is called the
Genotype
By the 1920s, scientists knew that proteins and DNA were the major chemical components of chromosomes
Each linear strand of the helix is made up of subunits called
nucleotides
In eukaryotic cells, the process leading to protein production begins in the nucleus with
Transcription
The synthesis of proteins under the direction of mRNA is called
Translation
The information encoded in mRNA (called the ———) consists of a linear series of nucleotide triplets. Each triplet, called a ——-
genetic code
codon
There are how many different amino acids commonly found in proteins
20
Protein assembly is accomplished with the aid of adapter molecules called
transfer RNA (tRNA)
tRNAs recognize the information encoded in the mRNA codons and carry the proper amino acids for construction of the protein during translation
They form the largest category of proteins
Enzymes
Enzymes serve as biological catalysts, lowering the energy of activation in reactions and allowing cellular metabolism to proceed at body temperature
Examples of proteins
- hemoglobin, the oxygen-binding molecule in red blood cells
- insulin, a pancreatic hormone
- collagen, a connective tissue molecule
- actin and myosin, the contractile muscle proteins
caused by a mutant form of hemoglobin
a mutation in the gene encoding β-globin causes an amino acid substitution in 1 of the 146 amino acids in the protein
a change in codon 6 in mRNA from GAG to GUG, which in turn changes amino acid number 6 in β@globin from glutamic acid to valine
mutant β-globin proteins cause hemoglobin molecules in red blood cells to polymerize when the blood’s oxygen concentration is low, forming long chains of hemoglobin that distort the shape of red blood cells
Sickle-cell anemia
recombinant DNA began in the early ——
1970s
used by bacteria to cut and inactivate the DNA of invading viruses, could be used to cut any organism’s DNA at specific nucleotide sequences, producing a reproducible set of fragments
restriction enzymes
Large amounts of cloned DNA fragments can be isolated from these bacterial host cells. These DNA fragments can be used to isolate genes, to study their organization and expression, and to study their nucleotide sequence and evolution
Collections of clones that represent an organism’s genome, defined as the complete haploid DNA content of a specific organism, are called
genomic libraries
The use of recombinant DNA technology and other molecular techniques to make products is called
biotechnology
What was the name of the Finn Dorset sheep that was cloned in 1996
Dolly the sheep (a Finn Dorset sheep)
What was the name of Dolly the sheep’s offspring
Bonnie