Introduction to Genetics (E-Book) Flashcards
What is the general process by which traits controlled by genes are transmitted from generation to generation?
Transmission genetics
Transmission genetics focuses on how genetic information is passed through gametes.
What technology revolutionized genetics and was the foundation for the Human Genome Project?
Recombinant DNA technology
This technology combines genetics with information technology.
Name one application of CRISPR-Cas technology.
Editing genomes
CRISPR-Cas allows for precise editing of genes across various organisms.
What are two systems developed for gene modification besides CRISPR-Cas?
- Zinc-finger nucleases (ZFNs)
- Transcription activator-like effector nucleases (TALENs)
These systems are currently undergoing clinical trials.
What does CRISPR stand for?
Clustered regularly interspersed short palindromic repeats
CRISPR is an RNA molecule synthesized to match DNA sequences.
True or False: Genetic technology is developing at a slower pace than the policies governing its use.
False
Genetic technology is developing faster than the policies and laws that govern its use.
What ethical concerns are raised by the genetic modification of human germ cells or embryos?
Unintended negative consequences for future generations
Modifications may affect the genetic information carried by descendants.
What was the theory proposed by William Harvey regarding organism development?
Theory of epigenesis
This theory states that an organism develops through successive developmental events from the fertilized egg.
Who proposed the cell theory in the 1830s?
Matthias Schleiden and Theodor Schwann
The cell theory states that all organisms are composed of cells derived from preexisting cells.
What did Charles Darwin’s theory of natural selection explain?
Mechanism of evolutionary change
Natural selection is based on the struggle for survival among individuals with heritable traits.
Fill in the blank: The revolutionary work of _____ and _____ set the stage for the development of genetics in the 20th century.
Charles Darwin, Gregor Mendel
Their work provided critical insights into evolution and inheritance.
What is the chromosomal theory of inheritance?
Heredity and development depend on genetic information in genes contained in chromosomes
This theory was established in the early 20th century.
What did Gregor Mendel’s research in 1866 demonstrate?
How traits are passed from generation to generation
Mendel’s work laid the foundation for the field of genetics.
What is the most commonly used Cas nuclease in CRISPR technology?
Cas9
Cas9 is a DNA-cutting enzyme used in many laboratory experiments.
What was one of the applications of CRISPR-Cas technology in agriculture?
Creating disease-resistant strains of crops
This includes crops like wheat and rice.
True or False: The ideas of Hippocrates and Aristotle about heredity were based on modern genetic principles.
False
Their ideas were primitive and lacked scientific basis as understood today.
in the twenty-first century is built on a rich
tradition of discovery and experimentation stretching
from the ancient world through the nineteenth century
to the present day
genetics
is the general process by which
traits controlled by genes are transmitted through
gametes from generation to generation
transmission genetics
can be used in genetic crosses to
map the location and distance between genes on
chromosomes
mutant strains
what model of DNA structure explains
how genetic information is stored and expressed.
Watson-Crick Model
foundation of molecular genetics.
Watson-Crick Model
revolutionized genetics,
was the foundation for the Human Genome Project, and
has generated new fields that combine genetics with
information technology
recombinant DNA technology
what does recombinant DNA technology enabled (3)
revolutionized genetics
foundation for Human Genome Project
generated new fields that combine genetics with information technology
provides genetically modified organisms and their products that are used across a wide range of fields including agriculture, medicine, and industry
biotechnology
fields where biotechnology is used
agriculture
medicine
industry
model organisms used in genetics are now utilized in combination with what to study human disease
recombinant DNA technology
genomics
the study of an organism’s genome – its genetic material – and how that information is applied.
genomics
is developing faster than the policies, laws, and conventions that govern its use
genetic technology
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
CRISPR-Cas
Cas means
CRISPR Associated
the ultimate tool in genetic technology,
whereby the genome of organisms, including humans, may
be precisely edited
CRISPR-Cas
ZFN meaning
zinc finger nucleases
TALENs meaning
transcription activator-like effector nucleases
were initially discovered as a molecular complex that protects bacterial cells from invasion by viruses
CRISPR-Cas molecules
CRISPR-Cas molecules protects bacterial cells from invasion of what microorganism
viruses
CRISPR designates an ___ molecule, which in the laboratory can be synthesized to match
any DNA sequence of choice
RNA
how many ends does CRISPR RNA have
two
first end of CRISPR RNA includes
recognizes and binds to a matching DNA sequence in the
gene of interest
second end of CRISPR RNA
other binds to a CRISPR-associated
(Cas) nuclease, or DNA-cutting enzyme.
most common Cas nuclease
Cas 9
In laboratory
experiments, CRISPR-Cas systems have already been used
to repair mutations in cells derived from individuals with
several genetic disorders, including what diseases
cystic fibrosis
Huntington disease
beta-thalassemia
sickle cell disease
muscular dystrophy
X-linked retinitis pigmentosa
disease where CRISPR-Cas systems can treat; can lead to progressive vision loss
X-linked retinitis pigmentosa
In the ___ ___ a clinical trial
using CRISPR-Cas9 for genome editing in cancer therapy
has been approved, and a second proposal for treating a
genetic form of blindness is in preparation
United States
A clinical trial
using CRISPR-Cas9 for cancer therapy is already under way
in C
China
CRISPR Cas was also used by a group to prevent mosquitoes from carrying the parasite that cause
malaria
other use of CRISPR-Cas aside from genetic cancer therapy and preventing mosquitos to have the malaria-causing gene
engineer laboratory grown human blood vessels and organs to prevent rejection of translated tissues and organs
create disease resistant strains of wheat and rice
what archaeological evidence documented the the successful domestication of
animals and the cultivation of plants thousands of years
ago by the artificial selection of genetic variants from wild
populations
pictorial representations
preseved bones and skulls
dried seeds
Between ____ and ____b.c., horses, camels,
oxen, and wolves were domesticated, and selective breeding of these species soon followed. C
8000-1000
Between 8000 and 1000 b.c., what animals were domesticated, and selective breeding of these species soon followed. C
horses
camels
oxen
wolves
Cultivation of many
plants, including maize, wheat, rice, and the date palm,
began around ___ b.c.
5000
During the ___ _____of Greek culture, the writings
of the Hippocratic School of Medicine (500–400 b.c.) and
of the philosopher and naturalist Aristotle (384–322 b.c.)
discussed heredity as it relates to humans.
Golden Age
During the Golden Age of Greek culture what writings discussed heredity as it relates to humans
Hippocratic School of Medicine
Aristotle’s writings
what The Hippocratic treatise argued that active “humors” in
various parts of the body served as the bearers of hereditary traits.
on the seed
Drawn from various parts of the male body to
the semen and passed on to offspring, these ____ could
be healthy or diseased, with the diseased humors accounting for the appearance of newborns with congenital disorders or deformities. I
humors
accounting for the appearance of newborns with congenital disorders or deformities according to the seed
diseased humors
extended Hippocrates’ thinking and 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
Aristotle
Aristotle proposed that the human semen contained a
vital heat
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
Aristotle
menstrual blood produced by the female, which was the “___ _____ ”
that gave rise to an offspring
physical substance
embryo developed
because it already contained the parts of an adult in miniature form
who thought this way
Hippocratics
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
when did , major strides provided insight into the biological basis
of life.
1600-1850 (dawn of modern biology)
studied reproduction
and development and proposed the theory of epigenesis
William Harvey
which states that an organism develops from the fertilized
egg by a succession of developmental events that eventually
transform the egg into an adult
epigenesis
The theory of epigenesis
directly conflicted with the theory of
preformation
which
stated that the fertilized egg contains a complete miniature
adult
preformation
e theory of preformation, which
stated that the fertilized egg contains a complete miniature
adult, called a
homonculus
proposed the
cell theory
Matthias Schleiden
Theodor Schwann
stating that all organisms are composed of
basic structural units called cells
cell theory
the
creation of living organisms from nonliving components
spontaneous generation
spontaneous generation was later disproved by
Louis Pasteur
In the mid-1800s the revolutionary works of what scientsist set the stage for the rapid development of genetics in the twentieth and twenty-first centurie
Charles Darwin
Gregor Mendel
Charles Darwin published this book that describes his ideas about evolution
The Origin of Species
Darwin is greatly influenced by his voyage on what ship
HMS beagle
Darwin’s thinking led him to formulate the theory of
natural selection
which presented an explanation of the
mechanism of evolutionary change.
theory of natural selection
according to him, 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.
Alfred Russel Wallace
published a paper in 1866 showing how
traits were passed from generation to generation in pea
plants and offering a general model of how traits are inherited
Gregor Johann Mendel
Gregor Johann Mendel’s research was little known until it was partially
duplicated and brought to light by
Carl Correns
Hugo de Vries
Erich Tschermak
heredity and development were dependent on
genetic information residing in genes contained in chromosomes, which were then contributed to each individual
by gametes
what theory
chromosomal theory of inheritance
the starting point of genetics was in
monastery garden in central Europe in late 1850s
an Augustinian monk, conducted a decadelong series of experiments using pea plants. H
Gregor Mendel
Gregor Mendel further concluded that each trail in the plant is controlled by a pair of ___
factors (now known as genes)
formation of eggs and sperm
gamete formation
defined as the branch of biology concerned with the
study of heredity and variation.
genetics
About ___ years after Mendel’s work
was published, advances in microscopy allowed researchers to identify chromosomes
20
in most eukaryotes, members of each species have a
characteristic number of chromosomes called the
diploid
how many diploid number does humans have
46
Chromosomes in diploid cells exist in pairs, called
homologous chromosomes
two forms of cell division
mitosis
meiosis
chromosomes are copied and distributed
so that each daughter cell receives a diploid set of chromosomes identical to those in the parental cell
what kind of cell division
mitosis
cell division associated with gamete formation
meiosis
. Cells produced by ____ receive only one chromosome from each chromosome
pair, and the resulting number of chromosomes is called
the haploid number (n
meiosis
. Cells produced by meiosis receive only one chromosome from each chromosome
pair, and the resulting number of chromosomes is called
the ___
haploid number
why is the reduction of chromosome from diploid to haploid important?
if the offspring arising from the fusion
of egg and sperm are to maintain the constant number of
chromosomes characteristic of their parents and other
members of their species
A colorized image of the human male
chromosome set. Arranged in this way, the set is called a
karyotype
is an individual’s complete set of chromosomes
karyotype
Early in the twentieth century, ___ __ and
____ _____ independently noted that the behavior of chromosomes during meiosis is identical to the behavior of genes during gamete formation described by Mendel
Walter Sutton
Theodor Boveri
Sutton and Boveri independently formulated what theory
chromosome theory of inheritance
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
About the same time that the chromosome theory of inheritance was proposed, scientists began studying the inheritance of traits in the
fruit fly
scientific name of fruitfly that scientists were studying the inheritance of traits
Drosophilia melanogaster
Early
in this work, a ___-eyed fly (Figure 1.6) was discovered
among normal (wild-type) red-eyed flies.
white
variation produced where white eyed flies can occur in red-eyed flies Drosophilia melanogaster
mutation
are defined as any heritable change in
the DNA sequence and are the source of all genetic variation
mutation
The white-eye variant discovered in Drosophila is an
___ of a gene controlling eye color
allele
are defined as
alternative forms of a gene.
allele
observable features of an organism
phenotype
The set of alleles for a given trait carried by
an organism is called the
genotype
Using ___ genes as
markers, geneticists can map the location of genes on chromosome
mutant
By the ___,
scientists knew that proteins and DNA were the major
chemical components of chromosomes
1920s
There are a large
number of different proteins, and because of their universal distribution in the nucleus and cytoplasm, many
researchers thought ___ were the carriers of genetic
information.
proteins
published experiments showing that DNA was the carrier of genetic information in bacteria
Oswald Avery
Colin MacLeod
Maclyn McCarty
Additional evidence for the role of DNA as a carrier of genetic
information came from ___ and ___ who worked with
viruses
Hershey
Chase
One of the great discoveries of the twentieth century was
made in 1953 by __ ____ and ____ ____, who
described the structure of DNA
James Watson
Francis Crick
is a long, ladderlike macromolecule that twists to form a double helix
DNA
Each linear strand of the helix is made up of
subunits called n
nucleotide
In DNA, there are four different nucleotides, each of which contains a nitrogenous
base,
Adenine
Guanine
Thymine
Cytosine
scientists awarded a Nobel Prize in 1962 for
their work on the structure of DNA.
James Watson
Francis Crick
Maurice Wilkins
is chemically similar to
DNA but contains a different sugar
RNA
RNA has a nitrogenous base called ___ instead of thymine
uracil
what bond hold together two strands of DNA helix
hydrogen bonds
is a chemical bond that forms the backbone of DNA and RNA molecules
phopshodiester bond
The genetic information encoded in the order of nucleotides
in DNA is expressed in a series of steps that results in the
formation of a functional gene product. In the majority of
cases, this product is a
protein
In eukaryotic cells, the process leading to protein production begins in the nucleus with
transcription
in which the nucleotide sequence in one
strand of DNA is used to construct a complementary RNA
sequence (
transcription
Once an RNA molecule
is produced, it moves to the cytoplasm, where the RNA—
called ____ binds to a ribosome
messenger RNA or mRNA
The synthesis of proteins under the direction of
mRNA is called
translation
The
information encoded in mRNA
genetic code
genetic code consists of a linear series of nucleotide triplets. Each triplet,
called a
codon
Proteins (lower part of Figure 1.8) are polymers made up of ____ ___ monomers.
amino acid
how many amino acids are commonly found in proteins
20
is accomplished with the aid of
adapter molecules called transfer RNA (tRNA)
protein assembly
recognize the information encoded in
the mRNA codons and carry the proper amino acids for construction of the protein during translation
tRNA (transfer RNAs)
In most cases, ___are the end products of gene expression
proteins
form the largest category of proteins
enzymes
molecules serve as biological catalysts, lowering the energy
of activation in reactions and allowing cellular metabolism
to proceed at body temperature
enzymes
oxygen-binding molecule in red blood cells
hemoglobin
a pancreatic hormone
insulin
a connective tissue molecule
collagen
the contractile muscle proteins
actin
myosin
Consider that a protein chain containing 100
amino acids can have at each position any one of 20 amino
acids; the number of possible different 100-amino-acid proteins, each with a unique sequence, is therefore equal to
20^100
A protein’s shape and chemical behavior are determined by
its
primary structure (linear sequence of amino acids)
Once a protein is made, its biochemical or structural properties play a role in producing a ____
phenotype
is caused by a mutant form of hemoglobin, the protein that transports oxygen from the lungs
to cells in the body
sickle cell anemia
is a composite molecule
made up of two different proteins, α-globin and β-globin,
each encoded by a different gene.
hemoglobin
hemoglobin is made up of two proteins called
a-globin
b-globin
difference between B-globin and mutant b-globin
protein 6
normal - Glu
Mutant - Val
a normal b-globin has this amino acid in its 6th spot
Glut
a mutant b-globin has this amino acid in its 6th spot
Valine
ndividuals with two mutant copies of the β@globin gene
have
sickle-cell anemia
what does mutant b-globin proteins cause hemoglobin molecules in RBC
polymerize when blood O2 concentration is low, forming long chains of hemoglobin that distort the shape of red blood cell
is an insufficiency of red blood cells
anemia
Sickle-shaped
blood cells block blood flow in ___ and small blood
vessels, causing severe pain and damage to the heart, brain,
muscles, and kidneys.
capillaries
The era of recombinant DNA began in the early 1970s,
when researchers discovered
restriction enzymes
used by bacteria to cut and inactivate the DNA of invading
viruses
restriction enzymes
could be used to cut any organism’s DNA at specific nucleotide sequences, producing a reproducible set of
fragments
restriction enzymes
Soon after, researchers discovered ways to insert the
DNA fragments produced by the action of restriction enzymes
into carrier DNA molecules called
vectors
When transferred into bacterial cells,
thousands of copies, or ____, of the combined vector and
DNA fragments are produced during bacterial reproduction.
clones
defined as the complete haploid DNA content of
a specific organism
genome
Collections of clones that represent an organism’s
genome
genomic libraries
has not only accelerated the pace of research but also given rise to the biotechnology industry, which has grown to become a major
contributor to the U.S. economy.
recombinant DNA technology
The use of recombinant DNA technology and other molecular techniques to make products is called
biotechnology
The transfer of heritable traits across species using recombinant DNA technology creates
transgenic organisms
refers to an organism or cell that has had its genome altered by introducing foreign DNA from another species
transgenic
. In 1996,
____ ___ (Figure 1.11) was cloned by nuclear transfer, a method in which the nucleus of an adult cell is transferred into an egg that has had its nucleus removed
Dolly the Sheep
, a method in which the nucleus of an adult cell is transferred into an egg that has had its nucleus removed
nuclear transfer
In 2009, an ____ proteinderived from the
milk of transgenic goats was approved by the U.S. Food and
Drug Administration for use in the United States.
anti-clotting
In 2009, an anticlotting protein derived from the
milk of transgenic ___was approved by the U.S. Food and
Drug Administration for use in the United States.
goat
is
now available to perform prenatal diagnosis of heritable
disorders and to test parents for their status as “carriers” of more than 100 inherited disorders.
biotecnology-derived genetic testing
This sequence information would be used
to identify each gene in the genome and establish its function
sequencing of clones in a library to derive nucleotide sequence
international effort to sequence the human
genome.
Human Genome Project
By ____, the publicly funded Human Genome Project and a private, industry-funded genome project completed
sequencing of the gene-containing portion of the genome
2003
study of genomes
genomics
studies the structure, function, and evolution of genes and genomes
genomics
identifies the set of proteins present in a cell under a given
set of conditions, and studies their functions and interactions
proteomics
s. To store, retrieve, and analyze the massive amount of
data generated by genomics and proteomics, a specialized
subfield of information technology called
bioinformatics
to develop hardware and software for processing nucleotide and protein data.
bioinformatics
Geneticists and other biologists now use information
in databases containing
nucleic acid sequences
protein sequences
gene-interaction networks
approach essential for studying and understanding gene function. In this approach geneticists relied
on the use of naturally occurring mutations or intentionally induced mutations (using chemicals, X-rays or UV light
as examples) to cause altered phenotypes in model organisms, and then worked through the lab-intensive and timeconsuming process of identifying the genes that caused these
new phenotypes
classical or forward genetics
approaches are still used, but as
whole genome sequencing has become routine, molecular
approaches to understanding gene function have changed
considerably in genetic research. These modern approaches
are what we will highlight in this feature.
classical genetics
the DNA sequence for a particular gene of interest is known, but the role and function of the gene are typically
not well understood
reverse genetics
t render targeted genes nonfunctional in a model organism or in cultured cells, allowing
scientists to investigate the fundamental question of “what
happens if this gene is disrupted?”
gene knockout
mouse scientific name
Mus musculus
defined as organisms used for the study of basic biological processes.
model organisms
microbes that are model organism for genetic studies
Saccharomyces cerevisiae
Escherichia coli
model organisms for Colon cancer and other cancers
e coli
model organisms for Cancer, Werner syndrome
S. cerevisiae
model organism for Disorders of the nervous system, cancer
Drosophilia melanogaster
model organism for diabetes
C. elegans (Caenorhabditis elegans); Roundworm
model organism for cardiovascular disease
Danio rerio (Zebrafish)
model organism for Lesch–Nyhan disease, cystic fibrosis,
fragile-X syndrome, and many other
diseases
Mus musculus
virus model organism
T phages
Lambda phage
was chosen as a model
system to study the development and function of the nervous system because its nervous system contains only a few
hundred cells and the developmental fate of these and all
other cells in the body has been mapped out
Caernohabditis elagans
a small plant with a short life cycle, has become a
model organism for the study of many aspects of plant biology.
Arabidopsis thaliana (Thale cress)
is used to study vertebrate
development: it is small, it reproduces rapidly, and its egg,
embryo, and larvae are all transparent.
Zebrafish (dario reerio)
a process that is defective in some
forms of colon cancer
DNA repair
gene involved in DNA repair
mutL in e coli
MLH1 in humans
Mutant genes
have been identified in __ ____ that produce phenotypes with structural abnormalities of the nervous system
and adult-onset degeneration of the nervous system
Drosophilia Melanogaster
For
example, genes involved in a complex human disease of the
retina called _____ ____are identical to Drosophila genes involved in retinal degeneration.
Retinitis pigmentosa
Another approach to studying diseases of the human
nervous system is to transfer mutant human disease
genes into Drosophila using
recombinant DNA technology
Mendel described his decade-long project on inheritance
in pea plants in an 1865 paper presented at a meeting of
the
Natural History Society of Brunn in Moravia
the Nobel Prize was given to ___ for his research on the chromosome theory
of inheritance.
Thomas Morgan
___ work on pea plants established the principles of gene
transmission from parents to offspring that form the foundation
for the science of genetics
Mendel
are the fundamental units in the chromosomal theory of inheritance
Gene
Chromosome
based on the central dogma that DNA is a
template for making RNA, which encodes the order of amino acids
in proteins—explains the phenomena described by Mendelian
genetics, referred to as transmission genetics
molecular genetics
a far-reaching methodology used
in molecular genetics, allows genes from one organism to be
spliced into vectors and cloned, producing many copies of specific
DNA sequences
recombinant DNA technology
has revolutionized agriculture, the pharmaceutical
industry, and medicine. It has made possible the mass productionof medically important gene products.
biotechnology
allows
detection of individuals with genetic disorders and those at risk
of having affected children, and gene therapy offers hope for the
treatment of serious genetic disorders
genetic testing
are new fields
derived from recombinant DNA technology
genomics
proteomics
bioinformatics
one xample of genomics
human genome project
The use of ___ organisms has advanced the understanding of
genetic mechanisms and, coupled with recombinant DNA technology, has produced models of human genetic diseases
model
is the science of heredity and variation
Genetics
is the transmission of traits from generation to generation while variation deals with genetic differences between organisms.
Heredity
Genetics as a scientific discipline, stemmed from the work of ____ ___ in the mid of 19th century, suspecting that traits are inherited as discrete units (Mendelian Factor) and became the basis for the development of present understanding of heredity.
Gregor Mendel
As a scientific discipline, it stemmed from the work of Gregor Mendel in the mid of 19th century, suspecting that traits are inherited as discrete units called
Mendelian Factor
Although development in genetics was greatly contributed by Mendel’s discovery of laws governing inheritance of trait, it was ____ ____, an English biologist in 1905, who coined the term Genetics.
William Bateson
proposed the “Theory of Inheritance of Acquired Characteristics”.
Jean Baptiste Lamarck
Jean Baptiste Lamarck is a ___ biologist
French
As per his ideology, the ___ characteristics by living in a particular environment are transferred over to the later generations.
acquired
published the results of his experiments with pea plants. His work later provided the mathematical foundation of the science of genetics.
Gregor Mendel
Gregor Mendel is an ____ botanist
Austrian
proposed the idea that the hereditary material resides in the nucleus.
Earnst Haeckel
Earnst Haeckel is a ___ zoologist
German zoologist
proposed his pangenesis theory to describe the units of inheritance between parents and offspring and the processes by which those units control development in offspring.
Charles Robert Darwin
Charles Robert Darwin’s theory that describe the units of inheritance between parents and offspring and the processes by which those units control development in offspring.
Pangenesis
Charles Robert Darwin is a ___ biologist
English
became the first to isolate nuclein. Further experiments (1874) revealed nuclein consisted of a nucleic acid and protein.
Johann Friedrich Miescher
observed the chromosomes during cell division. Terms chromatin, mitosis, cytoplasm, nucleoplasm, prophase and metaphase are coined.
(3)
Walther Flemming
Eduard Strasburger
Edouard van Beneden
described the term chromosome as condensed form of material found in the nucleus.
Heinrich Wilhelm Gottfried von Waldeyer-Hartz
introduced the germplasm theory wherein inheritance (in a multicellular organism) only takes place by means of the germ cells—the gametes such as egg cells and sperm cells.
August Weissman
wherein inheritance (in a multicellular organism) only takes place by means of the germ cells—the gametes such as egg cells and sperm cells.
germplasm theory
Mendel’s experiments were rediscovered independently by which scientists (3)
Hugo de Vries
Carl Erich Correns
Erich Tschermak von Seysenegg
introduced the concept that specific chromosomes are responsible for determining sex in animals.
Clarence Erwin McClung
proposed the chromosomal theory of inheritance identifying the chromosomes as the carriers of genetic material. (2)
Walter Sullton
Theodor Boveri
used the terms genetics, homozygote, heterozygote, epistasis, F1, F2 and allelomorph (allele).
Willian Bateson
experimented on sweet pea and demonstrated the concept of linkage. They also observed that several genes alter or modify the action of other genes.
William Bateson
Reginald Punett
discovered the presence of lethal genes in mouse.
Lucien Claude Cuenot
independently discovered the X-Y determination system.
Nielle Stevens
Edmund Wilson
g formulated the Hardy-Weinberg principle of genetic equilibrium. This is a unifying theory that underlies population genetics.
Godfrey Harold Hardy
Wilhem Weinberg
This is a unifying theory that underlies population genetics
Hardy-Weinberg principle of genetic equilibrium
coined the terms gene, genotype and phenotype.
Wilhem Johannsen
use Drosophila to demonstrate sex linkage.
Thomas Hunt Morgan
developed first genetic map in Drosophila.
Alfred Henry Sturtevant
observed non-disjunction in sex chromosomes. He also observed the presence of deficiencies (1917), duplication (1919) and translocation (1923) in Drosophila.
Calvin Bridges
conducted experiments suggesting that bacteria are capable of transferring genetic information and that such transformation is heritable.
Frederick Griffith
published a paper demonstrating that new allelic combinations of linked genes are correlated with physically exchanged chromosome parts. Their findings suggested that chromosomes form the basis of genetics.
Harriet Creighton
Barbara McClintock
demonstrated the one gene, one enzyme concept in Neurospora.
George Beadle
Edward Tatum
reported that the transforming substance—the genetic material of the cell—was DNA. This fact was lost, and this discovery is often afforded to Hershey and Chase (1953) – The Blender Experiment.
Oswald Avery
Maclyn McCarty
Colin Macleod
Oswald Avery, American biologists, Maclyn McCarty, and Colin MacLeod reported that the transforming substance—the genetic material of the cell—was DNA. This fact was lost, and this discovery is often afforded to
Hershey and Chase (The Blender Experiment)
discovered the concept of transposable genes.
Barbara McClintock
discovered that the components of DNA are paired in a 1:1 ratio. Thus, the amount of adenine (A) is always equal to the amount of thymine (T), and the amount of guanine (G) is always equal to the amount of cytosine (C).
Erwin Chargaff
conducted X-ray diffraction studies that provided images of the helical structure of DNA strand.
Rosalind Franklin
Maurice Wilkins
Raymond Gosling
determined the molecular structure of DNA
James Watson
Francis Crick
introduced the central dogma of molecular biology.
Francis Crick
hypothesized that DNA replication follows a semiconservative mode.
Matthew Meselson
Franklin Stahl
published the “Genetic Regulatory Mechanism” / Lac operon controlling network in E. coli.
Jacques Monod
Francois Jacob
cracked the genetic code showing how nucleic acids with their 4-letter alphabet determine the order of the 20 kinds of amino acids in proteins
Marshall Nirenberg, Har Khorana, Severo Ochoa, Robert Holley
discovered restriction enzymes, which cleave DNA into fragments. The discovery, for which the three men shared the 1978 Nobel Prize for Physiology or Medicine, enabled scientists to manipulate genes by removing and inserting DNA sequences.
Werner Arber
Hamilton Othanel Smith
Daniel Nathans
developed some of the first techniques for DNA sequencing. Gilbert and Sanger shared the 1980 Nobel Prize for Chemistry for their work
Allan M. Maxam & Walter Gilbert and English biochemist Frederick Sanger
presented the first recombinant DNA molecule by splicing the bacterial and viral DNA. This was described as a general approach for mixing together two different DNA molecules
Paul Berg
established to be a database of all DNA sequences. Initially housed at the Los Alamos National Laboratory, it was transferred to National Center for Biotechnology Information (NCBI) in 1988.
GenBank
invented the polymerace chain reaction (PCR), a simple technique that allows a specific stretch of DNA to be copied billions of times in a few hours.
Kary Mullis
is launched. The goal is to “find all the genes on every chromosome in the body and to determine their biochemical nature.”
Human Genome Program
is published. It is estimated that the genome contains between 35,000 and 40,000 genes. Later (2002) estimates place the number at 30,000 genes.
human genome sequence
which was designed to identify genetic variations contributing to human disease through the development of a haplotype (haploidgenotype map of the human genome), began. By completion of Phase II of the project in 2007, scientists had data on some 3.1 million variations in the human genome.
International HapMap Project
an international collaboration in which researchers aimed to sequence the genomes of a large number of people from different ethnic groups worldwide with the intent of creating a catalog of genetic variations, began. The project was completed in 2015.
1000 Genome Project
how many are completed and on going genome in kingdom Viruses
2688 - complete
on going - N/A
how many are completed and on going genome in kingdom Microbes
c - 1,710
o - 6,085
how many are completed and on going genome in kingdom Fungi
c- 208
o - 205
how many are completed and on going genome in kingdom animalia
c - 182
o - 256
how many are completed and on going genome in kingdom plantae (+ agae)
c - 47
o -107
The following areas are the scope and applications of genetic studies and researches (4)
plant and animal improvement
medicine
legal applications
genetic engineering
Selective breeding involves choosing parents with particular characteristics to breed together and produce offspring with more desirable traits.
what area in application of genetic studies
plant and animal improvement
This includes studies of inheritance, mapping disease genes, diagnosis and treatment, and genetic counseling.
medicine
Genetics can be applied in legal situations such as criminal investigation and paternity disputes.
legal applications
has been used to mass-produce insulin, human growth hormones, follistim (for treating infertility), human albumin, monoclonal antibodies,
antihemophilic factors, vaccines, and many other drugs.
genetic engineering
