Chapter 1 Gen

Question 1

Genome

Answer 1

DNA found within all of our chromosomes

Question 2

Gene at the molecular level

Answer 2

46 human chromosomes were found in 23 pairs

Question 3

Transcription

Answer 3

the process of synthesizing RNA from a DNA template. or making a copy of it

Question 4

Translation

Answer 4

the process in which the sequence of codons within mRNA provides the information to synthesize the sequence of amino acids that constitute a polypeptide.

Question 5

Molecular level

Answer 5

Pigmentation gene

Question 6

Cellular Level

Answer 6

How the pigment is observed, to either be a little or a lot, in cells

Question 7

Organism Level

Answer 7

Looking at the creature and seeing if the pigment is there or not

Question 8

Population Levels

Answer 8

How this pigmentation affects a whole society of related creatures

Question 9

Gene Expression

Answer 9

the process by which the information within a gene is accessed, first to synthesize RNA and polypeptides, and eventually to affect the phenotype of the organism.

Question 10

The central dogma of biology/life

Answer 10

the idea that the usual flow of genetic information is from DNA to RNA to polypeptide (protein)

Question 11

Genetic code

Answer 11

the correspondence between a codon (i.e., a sequence of three bases in an mRNA molecule) and the functional role that the codon plays during translation. Each codon specifies a particular amino acid or the end of translation.

Question 12

The basic structure of DNA

Answer 12

Composed of a linear sequence of nucleotides. With four nitrogen-containing bases: adenine, thymine, guanine, and cytosine.

Question 13

How DNA encodes information for proteins

Answer 13

The sequence of a gene determines the amino acid sequence for the protein it encodes.

Question 14

Allele

Answer 14

an alternative version of a specific gene

Question 15

How alleles determine traits

Answer 15

They encode proteins that function as a blank-synthesizing enzyme

Question 16

How Proteins Determine Cellular Phenotypes

Answer 16

The unique relationship between gene sequences and protein structures is of paramount importance because the distinctive structure of each protein determines its function within a living cell or organism.

Question 17

How does this variability lead to a population that is enriched for a particular
trait that blends with the habitat following the action of natural selection
such as predation with respect to butterflies with different alleles for
pigmentation gene.

Answer 17

The butterflies with dark wings would avoid being eaten by birds if they lived in the dim light of a forest. The dark wings would help camouflage if the butterfly was perched on a dark surface like a tree trunk. The light-colored wings would help to camouflage the butterfly inhabiting a brightly lit meadow. A bird may be less likely to notice this butterfly if it is perched on a sunlit surface.

Question 18

How a mutation in the coding region of a gene may lead to
a change in the amino acid sequence of the corresponding polypeptide

Answer 18

A mutation in one nucleotide could change a codon to make a different amino acids, changing the polypeptide.

Question 19

The example of variability with respect to the sickle cell allele for
Hemoglobin and how it causes sickle cell anemia when present in
homozygous condition but offers a protective function against malarial
infection when present in the heterozygous state. Be able to justify why this
allele continues to be maintained in populations.

Answer 19

-In the homozygous condition: Only hemoglobin S is produced rather than the normal hemoglobin A. The red blood cells are then deformed into sickle-shaped cells after being subjected to low levels of oxygen. -In the heterozygous state: Sickle cell disease is not present, however, people benefit by an increased resistance to malaria. Red blood cells infected with malaria are likely to rupture, preventing the disease from spreading

Question 20

Be able to explain how the environment influences traits by interacting with genes using the example of phenylketonuria caused due to phenyl alanine hydroxylase deficiency.

Answer 20

Phenylketonuria (PKU): Humans possess a gene that encodes an enzyme known as phenylalanine hydroxylase. Most people have 2 functional copies of this gene. People with 1 or 2 functional copies of this gene can eat foods containing the amino acid phenylalanine and metabolize it properly. It’s rare for people to get 2 copies of a nonfunctional version of this protein which means that they cannot metabolize phenylalanine properly (about 1 in 8,000 births among Caucasians in the USA). People with this disorder can manifest a variety of detrimental traits, including mental retardation, underdeveloped teeth, and foul-smelling urine. PKU individuals can be identified at birth and raised on a restricted diet that is low in phenylalanine and they can develop normally.

Question 21

Karyotype

Answer 21

A photographic representation of all the chromosomes within a cell. It reveals how many chromosomes are found within an actively dividing somatic cell.

Question 22

Haploid

Answer 22

Contains half the number of chromosomes (23) (Ex: gametes: sperm and egg)

Question 23

What makes haploid cells?

Answer 23

Produced during meiosis, which is a cell division

Question 24

Diploid

Answer 24

Contains 2 copies of each chromosome, one from each parent. (Humans have 46 chromosomes, which are found in homologous pairs, except the sex chromosomes X and Y) -Process: Meiosis

Question 25

Be able to state the normal karyotype of a diploid cell in a male and female human being

Answer 25

46 chromosomes

Question 26

Be able to explain the genetic constitution (chromosomes) of male and female gametes from a human being

Answer 26

-there are 23 chromosomes in each gamete from male and females, however, female gametes contain an X chromosome, while half of the male gametes contain an X chromosome and the other have contains a Y chromosome.

Question 27

Be able to explain how a single cell the zygote is able to give rise to an
organism such as a human being with hundreds of different types of cells in
the body. Discuss this with respect to tissue-specific gene expression.

Answer 27

It allows us to appreciate the differences between the events in normal cellular processes and those that occur in disease pathogenesis

Question 28

Be able to explain the three major variations that are possible with respect to
genetic information (one at level of DNA sequence, two at levels of the
chromosomes i.e. structure or number) that may alter an organism’s traits

Answer 28

1) Gene mutations: alter the expression or function of a protein that a gene encodes
Result in genetic variation in which a gene is found in two or more alleles

2) A large segment of the chromosome can be lost, rearranged, or reattached to another chromosome.

3) Variation may occur in the total number of chromosomes

Question 29

Be able to explain what important goals for an organism does fertilization accomplish (eg restores diploidy, generates variability etc)

Answer 29

-The union of gametes, egg and sperm, during fertilization restores the diploid number of chromosomes. The primary advantage of sexual reproductionis that it enhances genetic variation. It can also result in new combinations of 2 or more traits that differ from those of either parent.

Question 30

Be able to explain the nature of defect associated with chromosomes for
Down syndrome. Be able to explain how having more number of
chromosomes may lead to a disease state. (compare with a normal diploid
state)

Question 31

Be able to explain how the Green Fluorescent protein is used as a tool in biology using the two examples mentioned in the text book.

Answer 31

Scientists were able to identify particular proteins in cells or specific body parts. Ex: GFP was used in mosquitoes to tell which is male and to sterilize them to help reduce the population.

Question 32

Genetic Cross

Answer 32

involves breeding 2 selected individuals and the subsequent analysis of their offspring in an attempt to understand how traits are passed from parent to offspring.

Question 33

Model System

Answer 33

particular species of animals that substitute for humans or other animals

Question 34

Cloning of Dolly the Sheep

Answer 34

was produced by the process of nuclear transfer. this involved scientists placing the nucleus of a body cell(an udder cell) from the sheep they wanted to clone into an empty egg cell that had had its nucleus removed. a short, sharp electric current helped the cell to start dividing. it was then implanted into another sheep to grow.

Question 35

Transmission Genetics

Question 36

Molecular Genetics

Question 37

Population Genetics