Chapter 1 - Genetics And Biotechnology

Question 1

1.

What are dominant and recessive traits?

Answer 1

Dominant traits:
Shows up when present (Capital letter)

Recessive traits:
Disappears with the dominant trait that is present (small letter)

Question 2

2.

State the 3 genetic rules that Mendal developed as a result of his study with pea plants

Answer 2

1. Assign letters to trait
2. Determine genotypes if parents
3. Make Punnet square

Question 3

3.
Go over the genetic terms 
1. Phenotype 
2. Genotype 
3. Heterozygous 
4. Homozygous 
5. Pure 
6. Hybrid
7. Alleles 
8. Homologous Chromosomes 
9. Monohybrid 
10. Dihybrid

Answer 3

Phenotype: 
Appearance of Trait 
Genotype: 
Gene combination 
Heterozygous: 
2 diff alleles 
Homozygous: 
2 identical alleles 
Alleles: 
One of the possible forms of a gene 
Homologous chromosomes: 
2 chromosomes that have the same kind of genes in the same order 
Monohybrid: 
2 parents differ in one pair of traits 
Dihybrid: 
2 parents differ in 2 pairs of traits 
Pure 
Homozygous trait 
Hybrid 
Heterozygous trait

Question 4

4.

Be able to do Monohybrid and dihybrid crosses

Answer 4

Doing good :)

Question 5

5.

Describe two of the exceptions to Mendals rules

Answer 5

1.incomplete dominance
The blending of 2 diff traits to get a 3rd intermediate phenotype

2. Multiple alleles
   - more than one pair of alleles is required to produce a trait

Question 6

6.

Be able to do crosses involving the exceptions

Answer 6

Keep going!

Question 7

7.

What is a pedigree and why do we use them?

Answer 7

Pedigree:

• A visual chart that depicts a family’s history of there genes.
• Can tell the possibilities of someone getting a disorder.

Question 8

8. 
What do each of the following mean when looking at a pedigree? 
1. Solid square 
2. Empty square 
3. Solid circle 
4. Empty circle 
5. half filled circle or square

Answer 8

1. Solid:
affected by the trait (male) 
(dominant or recessive) 
2. Empty: 
Not affected
Half empty: carrier of the trait or hybrid (heterozygous)

Question 9

9.

Be able to determine the genotype and resulting phenotype of individuals when using a pedigree

Answer 9

Doing great!

Question 10

10.

Describe gene flow

Answer 10

Gene flow:
The transfer of alleles or genes b/w populations

Changes the frequency of certain genes within a population

Look at paper

Question 11

11.

State a couple of factors that would reduce gene flow

Answer 11

Reduce gene flow:
-small population
Populations are far apart for each other

Question 12

12.

What is a Chromosome?

Answer 12

Chromosome:
Protein & DNA, ensures DNA is accurately copied and distributed

A thread like structure of nucleic acids and proteins

Carries genetic info in form of genes
Look at pic in binder

Question 13

13.

What does DNA stand for?

Answer 13

DeoxyriboNucleic Acid

Question 14

14.
Supercoiling of DNA allows it to fly into the cells. It also allows genes to be read or not. How is the reading of the genes determine by supercoiling

Answer 14

Tightly wounded-
gene isn’t read, so proteins aren’t made loosely wound-
gene is read so proteins are made

Question 15

15.

Compare somatic cells and gametes

Answer 15

Somatic cells-
All cells that aren’t apart of the reproductive system

Gamete cells-
Cells in the reproductive system

Question 16

16.

Compare chromatid and chromatin

Answer 16

Chromatid:
One half of a chromosome

Chromatin:
DNA with all of Gus proteins

Question 17

17.

Compare haploid and diploid

Answer 17

Haploid:
(n) half the number of chromosomes

Diploid:
(Zn) Contains two complete sets of chromosomes, one from each parent

Question 18

18.

How do the terms homologous chromosomes and sister chromatids relate?

Answer 18

Individual homologous chromosomes are made of sister chromatids

Question 19

19.

What is crossing-over?

Answer 19

Crossing over:

Switching genetic material b/w homologous chromosomes during meiosis

Question 20

20.

How are mitosis and meiosis similar and different

Answer 20

Similar:
Involves PMAT steps in which cells divide
Both allow for replication
Meiosis 11 is similar to Mitosis-> Chromosomes line up & sister chromatids are separated

Different:
Mitosis:
-cells splits to create 2 identical
Copies of the original cell
- Two identical daughter cells that are diploid
Meiosis:
-Cells split to form new cells with half the usual # of chromosomes
- includes 2 stages
-4 daughter cells are haploid & genetically different
-only egg and sperm cells

Question 21

21.

List two chromosomal abnormalities and describe them

Answer 21

Deletion:
part of chromosome missing

Inversion:
A inverted piece of chromosome

Question 22

22.

How does non-disjunction happen and why would it cause issues in the organism with these changes?

Answer 22

Non-disjunction:
Produces one cell with extra chromosomes and one cell lacking chromosomes because homologous chromosomes fail to segregate during meiosis

It would cause issues in the organisms because there would be two many proteins or not enough

Question 23

23.

How many chromosomes are in the usual human cell?

Answer 23

46 chromosomes or 23 pairs

Question 24

24.

What is a human karyotype and why are they useful?

Answer 24

Karyotype:
A pic of all chromosomes in a cell
They are in condensed form

They help us diagnose chromosomal abnormalities and disorders

Question 25

25. | What is the function of nucleic acids?

Answer 25

Transmits hereditary info traits make proteins and control cell activity

Question 26

26. | What are the 3 key components of nucleic acids?

Answer 26

1. A phosphate 2. A sugar 3. A nitrogenous base - Purines: Guanine and Adenine - Pyrimidines-Cytosine, Thymine, And Uracil

Question 27

27. | Of the nitrogenous bases, which are purines and which are Pyrimidines?

Answer 27

Purines: Guanine and adenine Pyrimidines: Cytosine, thymine and Uracil

Question 28

28. | Compare DNA and RNA

Answer 28

``` DNA: Has sugar Deoxyribose Double stranded molecules responsible for storing and transforming genetic info Has thymine and no Uracil can’t leave nucleus ``` ``` RNA has sugar ribose Single stranded molecule Directly codes for amine acids Acts as a messenger between DNA and ribosomes to make protein Small segment of Uracil Can leave Nucleus ``` Both Both carry genetic info

Question 29

29. | Be able to complete DNA chains when given one side of them

Answer 29

You got this :D

Question 30

30. | Briefly describe the process of DNA replication

Answer 30

Protein binds to origin on DNA Hydrogen bonds are broken, so the double helix “unzips” several points along the chain DNA polymerase (complex enzyme) bonds to the separated parent chains Enzyme moves along the chain and bonds proper new nucleotide to the parent chain

Question 31

31. | What is the result of DNA replication?

Answer 31

End result is two new DNA molecules that should be exact replicas of the parent. Each new DNA molecule has half of a parent DNA strand

Question 32

32. | What is transcription and why is it necessary?

Answer 32

Transcription: The process of making RNA from DNA it’s necessary because DNA is to big to get out of the nucleus so RNA is made (transcription) to get the message out to the cytoplasm for translation

Question 33

33. | Briefly describe how transcription happens

Answer 33

1. RNA polymerase bonds with DNA @ promoter site 2. RNA polymerase move along one strand 3. Nucleotides bonds with DNA 4. RNA polymerase moves past the site on the DNA, RNA strand detached at that point and the 2 strands of DNA join Moves along adding nucleotides until it reaches end of segment

Question 34

34. | What are some of the results of transcription?

Answer 34

a. Messenger RNA (mRNA) | b. Ribosomal RNA (rRNA) -> makes ribosomes

Question 35

35. | What is translation and why is it needed?

Answer 35

Translation: The assembly of amino acids to form proteins Needed to make proteins

Question 36

36. | Briefly describe the process of translation?

Answer 36

1. Ribosome attaches to mRNA 2. tRNA attaches to corresponding codon on mRNA 3. 2nd tRNA comes in, amino acids connect 4. 1st tRNA leaves 5. Process continues until a stop codon is reached 6. Results in new protein

Question 37

37. | Where do replication, transcription, and translation take place in a cell?

Answer 37

Translation: Outside the nucleus in the cytoplasm Transcription: nucleus Replication: Nucleus

Question 38

38. | What is the purpose of the proteins that are created through the translation process

Answer 38

To perform the functions of the cell so our body works

Question 39

39. | Be able to complete the process from DNA to proteins

Answer 39

On page

Question 40

40. | What is gene expression and why is it needed

Answer 40

Gene expression: Process that allows for the appearance of that gene encodes (brown hair) Allows genes to be made and for them to be used Need because not all cells need to do everything ex. Skins cells don’t need to be muscle cells

Question 41

41. | Name and describe two methods that alter the expression of genes

Answer 41

1. Transcriptional methods-> Changes when a gene is transcribed. Makes RNA happen more or less 2. Protein Controls-> Body will make proteins activate or not. Folding or unfolding of protein

Question 42

42. | What are the 3 epigenetic mechanisms for gene expression

Answer 42

DNA methylation: Enzymes attach methyl groups to DNA Often attached at the start of a gene Methylation usually “turns off” a gene b/c the methyl groups prevents the protein from attaching Acetyl groups: tends to activate genes Chromatin modification: chemicals attach to a Justine causing it to unwrap which allows transcription

Question 43

43 | Which method tends to turn “on” or “off” the genes? How is it done?

Answer 43

DNA methylation turn off the genes Acidic groups turn on the genes

Question 44

44. | State 2 causes of epigenetic changes

Answer 44

Exercise and alcohol

Question 45

45. | What are homeobox genes?

Answer 45

Homeobox genes: A group of genes that allow for proteins to be made that act as a transcription factor. This means they bind to and control others genes

Question 46

46. | An example of homeobox genes are HOX genes. What do these genes do to act as epigenetic factors in the cell?

Answer 46

They create proteins that act as tags on a gene so it is transcribed

Question 47

47. | Describe the 3 different gene mutations

Answer 47

1. Deletion: a nucleotide is left out 2. Insertion: a nucleotide is added 3. Point Mutation: one amino acid is substituted for another. The protein is usually functional

Question 48

48. | Why are insertions and deletions often fatal?

Answer 48

When you put in a Nucleotide it shifts the rest of the DNA molecule and so many amino acids are changed

Question 49

49. | State 2 causes of DNA mutations

Answer 49

Ultra violet radiation Cigarettes