Genetic Engineering/Human Genome Test Flashcards
What do humans accomplish by genetic engineering?
it takes advantage of naturally occuring genetic variation in plants, animals, and other organisms, to pass desired traits on to the generation of organisms.
hybridization
crossing dissimilar individuals to bring together the best of both organisms.
inbreeding
the continued breeding of inividuals with similar characteristics
what are the ultimate source of genetic variations?
mutations
How are changes made to DNA?
Scientists use their knowledge of the structure of DNA and its chemical properties to study and change DNA molecules,. Different techniques are used to extract DNA from cells, to cut DNA into smaller pieces, to identify the sequence of bases in a DNA molecule, and to make unlimited copies of DNA.
genetic engineering
making changes in the DNA code of a living organism
how do biologists get DNA out of a cell?
the cells are opened and the DNA is separated from the other cell parts.
restriction enzymes
each one cuts DNA at a specific sequence of nucleotides.
how can DNA fragments be separated?
one way is a procedure known as gel electrophresis
gel electrophresis
a mixture of DN fragments are placed at one end of a porous gel, and an electric voltage is applied to the ge;. When the power is turned on, DNA molecules, which are negatively charged, move toward the positive end of the gel.
recombinant DNA
DNA produced by combining DNA from diffrent sources
polymerase chain reaction
allows biologists to make unlimited copies of a strand of DNA
what happens during transformation?
a cell takes in DNA from outside the cell. This external DNA becomes a component of the cell’s DNA
plasmid
circular molecule of DNA and are found naturally in bacteria and have been very useful for DNA transfer.
genetic marker
a gene that makes it possible to distinguish bacteria that carry the plasmid (and the foreign DNA) frm those that don’t
what happens if transformation is successful?
the recombinant DNA is integrated into one of the chromosomes of the cell.
transgenic
contain genes from other species
biotechnology
a new industry that is changing the way we interact with the living world.
clone
a member of a population of genetically identical cells produced from a single cell
how was Dolly the sheep made?
- A donor cell is taken from a sheep’s udder and an egg cell is taken from an adult female sheep and the nucleus of the egg cell is removed.
- the two cells are fused using an electric shock. The fused cell begins dividing normally.
- The embryo is placed in the uterus of a foster mother. The embro develops into a lamb.
karyotype
a picture of chromosomes grouped in pairs
sex chromosomes
chromosomes that determine an individual’s sex ( X, X is a female, X,Y is a male)
autosomes
the 44 chromosomes that are not sex chromosomes
what gender is XX
female
what gender is XY
male
pedigree chart
shows the relationships within a family. can be used to infer the genotypes of family members
what are the known human blood groups
Rh and ABO
what are the genotypes of ABO
IAIA or IAi, IBIB or IBi, IAIB, ii
what are the genotypes for the Rh group
positive: Rh+/Rh+ or Rh+/Rh- Negative: Rh-/Rh-
what causes both sickle cell disease and cystic fibrosis?
a small change in the DNA of a single gene affects the structue of a protein, causing a serious genetic disorder
what is the difference between the normal and sickle cells?
sickle cells are bent and twisted in their shape and are more rigid than normal cells. they can’t hold oxygen that well either.
what makes an allele dominant, recessive, or codominant?
the nature of the gene’s protein product and its role in the cell
sex-linked genes
genes located on the sex chromosomes
what occurs in males since they have only one X chromosome
all X linked alleles are expressed in males, even if they are recessive
nondisjunction
occurs when homologous chromosomes fail to separate during meiosis. if nondisjunction occurs, abnormal numbers of chromosomes may find their way into gametes, and a disorder of chromosome numbers may result
what disorders can occur from nondisjunction?
down syndrome, turner’s and klinefelter’s
Dna finderprinting
analyzes sections of DNA that have little or no known function but vary widely from one individual to another
what is the human genome project?
an ongoing effort to analyze the human DNA sequence
what is gene therapy/ what happens in gene therapy?
the process of changing the gene that causes a genetic disorder/an absent or faulty gene is replaced by a normal, working gene
traits that are caused by the interaction of many genes are said to be
polyploidy
