genes and genetics

Question 1

what are the two important aspects of life do genes embody?

Answer 1

1) high fidelity replication (developmental processes)
2) information transfer (transfer of high fidelity information to offspring)

Question 2

fluid blending

Answer 2

model of inheritance that was similar to blending two liquids together. (chocolate+milk =chocolate milk that cannot be separated, but can be divided and redistributed)

Question 3

discrete particle model

Answer 3

correct model of inheritance similar to mixing together two sets of different colored marbles. the marbles can be mixed and separated to any extent, but different batches could be all one color and would sort independently.

Question 4

progeny

Answer 4

decendants/offspring

Question 5

genes

Answer 5

distinct factors of inheritance

Question 6

how are genes passed down?

Answer 6

each parents has two copies of each gene but only copy is passed down. copies may be identical. one allele from each trait is inherited from each parent (formed by a male and female gamete)

Question 7

dominant allele

Answer 7

An allele that expresses its phenotypic effect even when heterozygous with a recessive allele

Question 8

recessive allele

Answer 8

A type of allele that when present on its own will not affect the individual.

Question 9

principle of segregation

Answer 9

during gamete formation the pair of alleles that govern a trait separate (they stay together for the rest of the plants life, and separate when gametes form)

Question 10

principle of independent assortment

Answer 10

each trait’s allele is segregated independent of the others

Question 11

chromosomes

Answer 11

visible threads inside the nucleus of plant and animal cells that house the information needed for genetic development.

different chromosomes have different qualities .

sperm and egg nuclei combine to produce a cell with double the amount of chromosomes in a reaction.

Question 12

homologous pairs

Answer 12

nearly identical pairs in which chromosomes exist and then are sorted independently in gametes.

Question 13

linkage groups

Answer 13

A pair or set of genes that are close to each other on a chromosome and tend to be transmitted together - causes some traits to fail to sort independently.

Question 14

genetic crossover

Answer 14

during gamete formation some homologous chromosomes wrap around each other (causing breakage and swapping) that creates incomplete linkages.

ex. genes on the same chromosome can end up on separate gametes or alleles on separate chromosomes end up on the same chromosome.

Question 15

discovery of dna as a chemical component of genes (experiment)

Answer 15

german scientist took the pus from old bandages and isolated “nuclein” from the white blood cells, but was not seen as a genetically significant discovery due to its simplicity.

this was later found to be DNA and was linked to the role of proteins and chromosomes in genetics.

Question 16

griffith’s experiment - diplococcus pneumoniae

Answer 16

the bacteria that causes pneumonia exists in both a virulent (smooth) and nonvirulent strain (rought). a scientist killed the virulent strain and then mixed it with a live nonvirulent strain to be injected into mice. all the mice then died of pneumonia and it was discovered that the virulent strain (though dead) could still transform the non virulent strain.

Question 17

Hershey Chase experiment

Answer 17

confirmed DNA as the carrier of inheritance.

Alfred Hershey and Martha Chase injected T4 bacteriophages (bacterial virus) into cells. The T4 has a coating around the genetic material of the virus, as the cell manufactures more of the virus Hershey and Chase proved that only the DNA was transferred to offspring.

Question 18

Avery’s experiment

Answer 18

confirmed DNA as the transmitter of heredity.

Took smooth virulent bacteria strains and killed them to create extracts. the extracts were then treated with different enzymes. only the extract containing deoxynuclease was found to have genetically transforming principles.

Question 19

alleles

Answer 19

alternative forms of a gene