chapter 1

Question 1

what is genetics?

Answer 1

branch of biology that deals with heredity and variation

Question 2

what are genes?

Answer 2

segments of DNA that produce a functional product (RNA or polypeptide)

Question 3

what is genetic variation?

Answer 3

root of natural diversity from differences in SNP

Question 4

what are SNPs?

Answer 4

single nucelotide polyphormism- difference in one nucleotide

Question 5

who was hippocrates and what did he discover?

Answer 5

-first to attempt an explanation of heredity.
-believed seeds were from various parts and transmitted to offspring.
-healthy seeds from healthy parts and diseased seeds from diseased parts

Question 6

what did aristotle hypothesize?

Answer 6

-believed menstrual blood was the substance of reproduction, males provided heat that produced offspring
-offspring resembles parents due to spirits

Question 7

what is preformation?

Answer 7

embryo developed because it contained parts of an adult in miniature form

Question 8

what is epigenesis?

Answer 8

adult characteristics are not present at the beginning of conception but appear over the course of time.

Question 9

what did william harvey do?

Answer 9

believed an organism develops from a fertilized egg by developmental events that turn into the egg of an adult

Question 10

what did anton van leeuwenhoek do?

Answer 10

used microscope to observe sperm

Question 11

what is homunculus?

Answer 11

fully formed human inside the egg/sperm that would enlarge to make a new individual

Question 12

what did caspar friedrich wolff do?

Answer 12

cartried out studies of plant development and organ formation in chick embryos; argued that organs do not exists at the beginning of gestation

Question 13

robert brown

Answer 13

showed that an opaque spot called the nucleus was present in a variety of plant cells

Question 14

matthias schleiden

Answer 14

published research on plants indicating that they’re composed of cells

Question 15

theodor schwann

Answer 15

published that animal tissue is made of cells

Question 16

what did charles darwin do?

Answer 16

determined that species evolve by natural selection

Question 17

what did gregor mendel do?

Answer 17

-father of genetics
-pea plant experiment that concluded that traits are controlled by a pair of factors and during gamete formation, they split
-work ignored until 1900s

Question 18

how many chromosomes?

Answer 18

46 (diploid; 22 pairs + xx/xy)

Question 19

what did walther flemming do?

Answer 19

described the movement of chromosomes during cell division=mitosis

Question 20

what did walter sutton and theodor boveri do?

Answer 20

noted that the behaviour of chromosome in meiosis is identical to the behaviour of genes during gamete formation, described by mendel.

Question 21

what is the chromosome theory of inheritance?

Answer 21

traits are controlled by genes on the chromosome that are transmitted through gametes, maintaining genetic continuity from generation to generation

Question 22

what are alleles?

Answer 22

alternative forms of a gene
eg. normal white eye gene (1), mutant white eye gene (2)

Question 23

what are genotypes?

Answer 23

set of alleles for a given trait (Ff or Bb)

Question 24

what are phenotypes?

Answer 24

observable traits produced by the expression of the genotype

Question 25

who discovered that DNA was the carrier of genetic information?

Answer 25

avery macleod and mcCarty

Question 26

what was the mouse experiment?

Answer 26

live R bacteria took up DNA fragments from dead S bacteria and started expressing viral factors of the dead S bacteria- killing the mouse
-used DNase with s type extract and no transformation occured, concluding it was in the DNA

Question 27

what did james watson and francic crick do?

Answer 27

described the structure of DNA using xra crystallography from rosalind franklin

Question 28

what is each DNA strand made up of?

Answer 28

-a sugar (Deoxyribose) bonded to a phosphate + a nitrogenous base (A,T,C or G)
-A binds with T and C with G, with two strands running anti-parallel 5’-3’

Question 29

what is the structure of RNA?

Answer 29

single stranded, ribose sugar and uracil instead of thymine

Question 30

what is the central dogma and who discovered it?

Answer 30

states that gene expression occurrs by a series of steps that result in a functional gene product; DNA to RNA to protein; francis crick

Question 31

how do you link genotype to phenotype?

Answer 31

mutations that alter genes may modify or eliminate a proteins usual function, causing an altered phenotype

Question 32

what is an example of a mutation?

Answer 32

hemoglobin protein has a CTC codon, it gets mutated to CAC, created a different amino acid and changed the structure of the red blood cell causing it to stick to the capillaries= sickle cell anemia

Question 33

what are the types of traits?

Answer 33

morphological- physical appearance (flower colour)
physiological- cellular or body function (digesting lactose)
behavioral- ways organisms respond to environment ( mating calls)

Question 34

what are restriction enzymes?

Answer 34

can cut DNA at specific sites

Question 35

what is the process of cloning DNA sequences?

Answer 35

DNA fragments od interest are cut using restriction enzymes and inserted into a carrier DNA molecule called vectors, RDNA is then transferred to bacteria which would make thousands of copies.

Question 36

what are transgenic organisms?

Answer 36

genetically modified organisms to increase insect or viral resistance, nutritional enhancement or longer shelf life

Question 37

how are transgenic animals used in medicine?

Answer 37

antithrombin, an anticlotting protein that was expressed in the milk of transgenic goats was approved in 2009
- human gene producing normal amounts of antithrombin protein is inserted into goat DNA, then inserted into the nucleus of a fertilized goat egg and extracting the protein from the goat milk.

Question 38

how was dolly the sheep cloned?

Answer 38

nucleus from an adult sheep was placed in an embryo and grown

Question 39

why didn’t dolly the sheep live long?

Answer 39

the sheep used to clone molly was 6 years old meaning the telomeres were shortened, once cloned, the baby sheep had the telomeres and the DNA of an adult sheep making her age faster than normal.

Question 40

what are model organisms?

Answer 40

allows researchers to compare their results and determine scientific principles that apply to other species as well

Question 41

why do scientists use model organisms?

Answer 41

theyre easy to grow, have a short life cycle, produce many offspring and genetic anlysis is straight forward