Chapter 1 - Genetics And Biotechnology Flashcards
1.
What are dominant and recessive traits?
Dominant traits:
Shows up when present (Capital letter)
Recessive traits:
Disappears with the dominant trait that is present (small letter)
2.
State the 3 genetic rules that Mendal developed as a result of his study with pea plants
- Assign letters to trait
- Determine genotypes if parents
- Make Punnet square
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
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
4.
Be able to do Monohybrid and dihybrid crosses
Doing good :)
5.
Describe two of the exceptions to Mendals rules
1.incomplete dominance
The blending of 2 diff traits to get a 3rd intermediate phenotype
- Multiple alleles
- more than one pair of alleles is required to produce a trait
6.
Be able to do crosses involving the exceptions
Keep going!
7.
What is a pedigree and why do we use them?
Pedigree:
- A visual chart that depicts a family’s history of there genes.
- Can tell the possibilities of someone getting a disorder.
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
1. Solid: affected by the trait (male) (dominant or recessive) 2. Empty: Not affected Half empty: carrier of the trait or hybrid (heterozygous)
9.
Be able to determine the genotype and resulting phenotype of individuals when using a pedigree
Doing great!
10.
Describe gene flow
Gene flow:
The transfer of alleles or genes b/w populations
Changes the frequency of certain genes within a population
Look at paper
11.
State a couple of factors that would reduce gene flow
Reduce gene flow:
-small population
Populations are far apart for each other
12.
What is a Chromosome?
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
13.
What does DNA stand for?
DeoxyriboNucleic Acid
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
Tightly wounded-
gene isn’t read, so proteins aren’t made loosely wound-
gene is read so proteins are made
15.
Compare somatic cells and gametes
Somatic cells-
All cells that aren’t apart of the reproductive system
Gamete cells-
Cells in the reproductive system
16.
Compare chromatid and chromatin
Chromatid:
One half of a chromosome
Chromatin:
DNA with all of Gus proteins
17.
Compare haploid and diploid
Haploid:
(n) half the number of chromosomes
Diploid:
(Zn) Contains two complete sets of chromosomes, one from each parent
18.
How do the terms homologous chromosomes and sister chromatids relate?
Individual homologous chromosomes are made of sister chromatids
19.
What is crossing-over?
Crossing over:
Switching genetic material b/w homologous chromosomes during meiosis
20.
How are mitosis and meiosis similar and different
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
21.
List two chromosomal abnormalities and describe them
Deletion:
part of chromosome missing
Inversion:
A inverted piece of chromosome
22.
How does non-disjunction happen and why would it cause issues in the organism with these changes?
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
23.
How many chromosomes are in the usual human cell?
46 chromosomes or 23 pairs
24.
What is a human karyotype and why are they useful?
Karyotype:
A pic of all chromosomes in a cell
They are in condensed form
They help us diagnose chromosomal abnormalities and disorders
25.
What is the function of nucleic acids?
Transmits hereditary info
traits make proteins and control cell activity
26.
What are the 3 key components of nucleic acids?
- A phosphate
- A sugar
- A nitrogenous base
- Purines: Guanine and Adenine
- Pyrimidines-Cytosine, Thymine, And Uracil
27.
Of the nitrogenous bases, which are purines and which are Pyrimidines?
Purines: Guanine and adenine
Pyrimidines: Cytosine, thymine and Uracil
28.
Compare DNA and RNA
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
29.
Be able to complete DNA chains when given one side of them
You got this :D
30.
Briefly describe the process of DNA replication
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
31.
What is the result of DNA replication?
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
32.
What is transcription and why is it necessary?
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
33.
Briefly describe how transcription happens
- RNA polymerase bonds with DNA @ promoter site
- RNA polymerase move along one strand
- Nucleotides bonds with DNA
- 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
34.
What are some of the results of transcription?
a. Messenger RNA (mRNA)
b. Ribosomal RNA (rRNA) -> makes ribosomes
35.
What is translation and why is it needed?
Translation:
The assembly of amino acids to form proteins
Needed to make proteins
36.
Briefly describe the process of translation?
- Ribosome attaches to mRNA
- tRNA attaches to corresponding codon on mRNA
- 2nd tRNA comes in, amino acids connect
- 1st tRNA leaves
- Process continues until a stop codon is reached
- Results in new protein
37.
Where do replication, transcription, and translation take place in a cell?
Translation:
Outside the nucleus in the cytoplasm
Transcription: nucleus
Replication: Nucleus
38.
What is the purpose of the proteins that are created through the translation process
To perform the functions of the cell so our body works
39.
Be able to complete the process from DNA to proteins
On page
40.
What is gene expression and why is it needed
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
41.
Name and describe two methods that alter the expression of genes
- Transcriptional methods->
Changes when a gene is transcribed. Makes RNA happen more or less - Protein Controls->
Body will make proteins activate or not. Folding or unfolding of protein
42.
What are the 3 epigenetic mechanisms for gene expression
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
43
Which method tends to turn “on” or “off” the genes? How is it done?
DNA methylation turn off the genes
Acidic groups turn on the genes
44.
State 2 causes of epigenetic changes
Exercise and alcohol
45.
What are homeobox genes?
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
46.
An example of homeobox genes are HOX genes. What do these genes do to act as epigenetic factors in the cell?
They create proteins that act as tags on a gene so it is transcribed
47.
Describe the 3 different gene mutations
- Deletion: a nucleotide is left out
- Insertion: a nucleotide is added
- Point Mutation:
one amino acid is substituted for another. The protein is usually functional
48.
Why are insertions and deletions often fatal?
When you put in a Nucleotide it shifts the rest of the DNA molecule
and so many amino acids are changed
49.
State 2 causes of DNA mutations
Ultra violet radiation
Cigarettes
