Contemporary Biology - EXAM 2 (Hoops)

Microrays

(Also called gene chips) can screen genetic information, allowing doctors to look for specific mutations

Chromosome BEFORE DUPLICATION

- 2 homologous chromosomes - 1 from each parent - Contains the same genes - The alleles may be the same or different

DNA dependent DNA polymerase

- Makes complementary DNA based on the other strand - Can only elongate pre-existing strands, not start them - Only elongates in one direction

Chromosome AFTER DUPLICATION

- Still have two homologous chromosomes; 1 from each parent - But each chromosome is duplicated - In mitosis, the duplicated chromosomes are not physically matched - In meiosis, the chromosomes start out as matched - a tetrad

Chemotherapeutic Drugs

1. Alkylating Agents 2. Alkaloids 3. Taxanes 4. Antimetabolites 5. Topoisomerase inhibitors

Argument for those in favor of Booster Shots

1. Antibodies decrease over time 2. Pfizer's protection has not kept up with Moderna's 3. Older indv. may not be protected as well 4. Fully vaxxed but w/o boosters CAN spread diseases

Three Steps of PCR:

1. Denaturation (96 C) 2. Annealing (55 C) 3. Extension (72 C)

Two Types of Radiation Therapy

1. External Radiation Therapy 2. Internal Radiation Therapy

Experiment Order by Scientist

1. Griffith 2. Oswald Avery 3. Hershey and Chase 4. Erwin Chargaff 5. Rosalind Franklin 6. Watson and Crick

Outcomes of Gregor Mendel's Experiments

1. Inheritance comes in chunks 2. Many organisms have two sets of chunks 3. The next generation got one set of chunks from each parent 4. Some inheritance chunks can mask others (Mendel allowed numbers to be applied to how we inherit traits

Proteins vs. Nucleic Acids

1. Proteins = Large, diverse, Versatile Chemistry, Active 2. Nucleic Acids = Large, Non-diverse (Chemically). very limited chemistry, rare activity

Transcription in Gene Expression

1. RNA polymerase binds to an area at the start of a gene called a promoter 2. RNA polymerase unwraps a small section of the DNA, exposing the template strand of the DNA 3. RNA polymerase uses the template strand to make a complementary RNA copy, called messenger RNA

Translation in Gene Expression

1. Ribosome assembles around the mRNA codon to be processed 2. tRNA with an anticodon that complements it enters the ribosome with the first amino acid 3. A second tRNA, with an anticodon complementary to the second mRNA codon, enters the ribosome and a peptide bond is formed, with the first tRNA leaving 4. This process hits a stop codon, and then the protein is released

Arguments for those who are against Booster Shots

1. There are rare side effects 2. Moral question - giving a rich country a third shot while impoverished countries still don't have access 3. Since Vaxxed people can barely spread the virus, is this the best public use for vaccines

One kind of polydactyly (extra fingers) is chromosome based and dominant. It is also rare. Assume that a cell of a man with polydactyly is about to undergo meiosis. What would you expect about the chromatids in the homologous chromosomes? a)There would be 2 copies of the polydactyly allele and 2 copies of the wild-type allele in the cell. b)There would be 1 copy of the polydactyly allele and 1 copy of the wild-type allele in the cell. c)There would be a 50% chance of the cell having 2 copies of the polydactyly allele and a 50% chance of the cell having no copies of the polydactyly allele. d)There would be a 50% chance of the cell having 1 copy of the polydactyly allele and a 50% chance of having no copies of the polydactyly allele.

A - 2 copies

One kind of polydactyly (extra fingers) is chromosome based and dominant. It is also rare. Assume that a cell of a man with polydactyly is about to undergo mitosis. What would you expect about the chromatids in the homologous chromosomes? a)There would be 2 copies of the polydactyly allele and 2 copies of the wild-type allele in the cell. b)There would be 1 copy of the polydactyly allele and 1 copy of the wild-type allele in the cell. c)There would be a 50% chance of the cell having 2 copies of the polydactyly allele and a 50% chance of the cell having no copies of the polydactyly allele. d)There would be a 50% chance of the cell having 1 copy of the polydactyly allele and a 50% chance of having no copies of the polydactyly allele.

A - 2 copies

Hemoglobin

A complex protein that consists of four polypeptide chains, called globins (2 alpha, 2 beta)

Pedigree

A diagram that shows the occurrence of a genetic trait in several generations of a family. Males = squares, females = circles

Meiosis

A form of cell division that reduces the chromosome numbers of the daughter cells from diploid to haploid (This introduces variations) Involves 2 rounds, and results in the formation of four haploid cells

Taq polymerase

A heat resistant DNA-dependent DNA-polymerase (used in PCR)

Diagnostic Mammogram

A more detailed look at a specific area of the breast, usually because of a suspicious lump in the breast or blood test results associated with cancer

Gene

A segment of DNA that contains instructions for the production of a protein Genes are the basic unit of inheritance

Sickle-Cell Disease

A single mutation in a single gene causes the hemoglobin protein to change shape (genetic disease) A mutation in the bet-globin causes the normal glutamine amino acid (Glu) to be replaced by a valine (Val) amino acid

Biopsy

A surgical procedure to remove a small section of tissue to look for the presence of cancer cells.

Antigens

A target for the immune system (usually a protein) EX: A viral spike protein

Alleles

A variation of a gene, usually due to small changes in the nucleotide sequence within the gene

Computerized Tomography (CT) Scans (CAT scans)

A x-ray procedure used to take pictures of the organs from different angles to generate a 3D image. Useful for detecting whether cancer is spreading or not

If you analyzed the weight of the DNA strands at generation 0, you would expect: A)The conservative, semi-conservative and dispersed models to yield the same prediction. b)The conservative and semi-conservative models to yield the same prediction, but the and dispersed model to yield a different prediction. c)The conservative and dispersed models to yield the same prediction, but the and semi-conservative model to yield a different prediction. d)The semi-conservative and dispersed models to yield the same prediction, but the and conservative model yield a different prediction. e)The conservative, semi-conservative and dispersed models will all yield different predictions.

A.)The conservative, semi-conservative and dispersed models to yield the same prediction.

Oswald Avery Experiments

Added the enzyme DNase to Griffith's experiment. Worked with the mice.

Extension (PCR)

Adding base pairs or dNTPs to the strand so now we have twice as many copies (72 degrees Celsius) Step 3

Immunotherapy

An approach to treat cancer that helps the bodies immune system target cancer cells

Haploid

An organism or cell having only one complete set of chromosomes.

Genotype

An organism's genetic makeup, or allele combinations. (RR vs rr)

Phenotype

An organism's physical appearance, or visible traits. (straight vs wavy hair)

Order the following steps of PCR: step M: Primers bind to compl. seq. step N: Polymerase synthesizes new DNA step O: Heat to separate the DNA strands a)N, M, O b)O, M, N c)O, N, M

B

Which of the following is true about antibody treatments for COVID? a)They contain a single monoclonal antibody b)They contain a mixture of monoclonal antibodies c)They contain a single polyclonal antibody d)They contain a mixture of polyclonal antibodies

B

One kind of polydactyly is chromosome-based and dominant. It is also rare. Assume that a cell of a man with polydactyly is about to undergo meiosis. If you look at the tetrad, how many copies of the polydactyly allele would there probably be? a)1 b)2 c)3 d)4

B - 2 copies

One kind of polydactyly (extra fingers) is chromosome-based and dominant. It is also rare. Assume that a cell of a man with polydactyly is about to undergo meiosis. Would you expect the man to be heterozygous or homozygous for the polydactyly allele? a)Homozygous b)Heterozygous c)have a 50% chance of being heterozygous and a 50% chance of being homozygous.

B - Heterozygous

One kind of polydactyly (extra fingers) is chromosome-based and dominant. It is also rare. Assume that a cell of a man with polydactyly has undergone the first division of meiosis. What would you expect about the chromatids in the homologous chromosomes? a)There would be 2 copies of the polydactyly allele and 2 copies of the wild-type allele in the cell. b)There would be 1 copy of the polydactyly allele and 1 copy of the wild-type allele in the cell. c)There would be a 50% chance of the cell having 2 copies of the polydactyly allele and a 50% chance of the cell having no copies of the polydactyly allele. d)There would be a 50% chance of the cell having 1 copy of the polydactyly allele and a 50% chance of having no copies of the polydactyly allele.

C - 50% chance of 2 copies, 50% chance of no copies

Acute Chest Syndrome

Caused when the capillaries surrounding the alveoli become blocked by sickle-shaped RBCs

Alkaloids

Chemicals naturally produced by some plants; prevent cells from forming spindle fibers, thus preventing cell division (Disrupts cellular division)

Alkylating Agents

Chemicals that integrate into the DNA, causing it to break at specific points; general and so can cause long-term side effects including other cancers (DNA degradation)

One kind of polydactyly (extra fingers) is chromosome based and dominant. It is also rare. Assume that a cell of a man with polydactyly has undergone the second division of meiosis. What would you expect about the chromatids in the homologous chromosomes? a)There would be 2 copies of the polydactyly allele and 2 copies of the wild-type allele in the cell. b)There would be 1 copy of the polydactyly allele and 1 copy of the wild-type allele in the cell. c)There would be a 50% chance of the cell having 2 copies of the polydactyly allele and a 50% chance of the cell having no copies of the polydactyly allele. d)There would be a 50% chance of the cell having 1 copy of the polydactyly allele and a 50% chance of having no copies of the polydactyly allele.

D: 50% chance of 1 copy, 50% of no copies

Antimetabolites

DNA degradation

Denaturation (PCR)

DNA is heated to 96 degrees Celcius Step 1

Meselson Stahl

Determined that semi-conservative replication was the pathway in which DNA is replicated

Alfred Hershey and Martha Chase

Experimented with bacteriophage and used radioactive isotopes to determine that DNA NOT protein, is the genetic material in cells Proved: DNA is responsible for hereditary

Frederick Griffith Experiment (1920)

Experiments with pneumonia-causing bacteria indicated that a transforming factor could exchange information between strains (identified a piece of hereditary that can be transferred)

Heterozygous

Having different copies of alleles in an individual

Homozygous

Having two copies of the same allele

Erwin Chargraff

Identified the pattern of nucleotide base pairing. A =T , C=G

Mendel's Law of Segregation

Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete

Taxanes

Naturally produced by yew trees; prevent microtubule breakdown (Disrupts cellular division)

External Respiration

Occurs when red blood cells exchange gases with the environment at the alveoli

Internal Respiration

Occurs when red blood cells exchange gases with tissue cells of the body

Codominance

Occurs when two dominant alleles are expressed in the phenotype of an individual. EX: Blood types

Antibody

One of the several kinds of proteins made by the body that binds to the antigen (very specific, like lock and key)

Gregor Mendel

Performed classic experiments with pea plants to explain patterns of genetic inheritance. Determined inheritance as "chunks"

Topoisomerase Inhibitors

Prevents the unwinding of DNA so it cannot be access replicated

Annealing (PCR)

Primers base pair to the exposed DNA strands (55 C) Step 2

James Watson and Francis Crick

Put all of the experiments together to build a model of the double-helix DNA molecule

Red Blood Cells

Responsible for exchanging gases throughout the body - do not contain a nucleus, gives it its donut shape

Environmental Influences on Alleles

The environment can influence gene expression or the phenotype associated with it. EX: Skin color

Autosomes

The first 22 pairs of chromosomes.

Meiosis I

The first division of a two-stage process of cell division in sexually reproducing organisms that results in cells with half the number of chromosome sets as the original cell. Diploid -> 2 Haploid

Mendel's Law of Independent Assortment

The inheritance of one character has no effect on the inheritance of another

Heme

The iron in the middle of the hemoglobin

Epitopes

The many different spots on a virus/proteins that could be targets for antigens

AUG

The start codon

Chemist Rosaling Franklin

Used X-ray crystallography to examine the structure of DNA molecules Her experiments led to the realization that DNA is a double helix

Screening Mammogram

Used to detect abnormalities in the breast that may be associated with cancer

"Gain of function"

When an affiliation is dominant (Huntington's disease)

"Loss of function"

When an affiliation is recessive (sickle cell, cystic fibrosis)

Incomplete Dominance

When the dominant allele does not completely mask the recessive allele EX: Familia hypercholesterolemia Being heterozygous causes an intermediary expression of the allele)

Radiation Therapy

Works by damaging the DNA within a cell, with the intent to slow/stop cell division. (can also damage healthy cells)

Dispersive Replication

a disproved model of DNA synthesis suggesting more or less random interspersion of parental and new segments in daughter DNA molecules (completely chopping up and switching your DNA, original strand becomes full destroyed)

Complete Blood Count (CBC)

broad screening test used to evaluate red blood cells, white blood cells, and platelets to determine anemias, infections, and other diseases (cancer)

Diploid (2n)

containing two complete sets of chromosomes, one from each parent.

If you analyzed the weight of the DNA stands at after the first generation after transfer you would expect: a)The conservative, semi-conservative and dispersed models to yield the same prediction. b)The conservative and semi-conservative models to yield the same prediction, but the and dispersed model to yield a different prediction. c)The conservative and dispersed models to yield the same prediction, but the and semi-conservative model to yield a different prediction. d)The semi-conservative and dispersed models to yield the same prediction, but the and conservative model to yield a different prediction. e)The conservative, semi-conservative and dispersed models will all yield different predictions.

d)The semi-conservative and dispersed models to yield the same prediction, but the and conservative model to yield a different prediction.

If you analyzed the weight of the DNA stands at after the second generation after transfer you would expect: a)The conservative, semi-conservative and dispersed models to yield the same prediction. b)The conservative and semi-conservative models to yield the same prediction, but the and dispersed model to yield a different prediction. c)The conservative and dispersed models to yield the same prediction, but the and semi-conservative model to yield a different prediction. d)The semi-conservative and dispersed models to yield the same prediction, but the and conservative model to yield a different prediction. e)The conservative, semi-conservative and dispersed models will all yield different predictions.

e)The conservative, semi-conservative and dispersed models will all yield different predictions.

Semiconservative DNA Replication

each daughter DNA molecule is composed of one original strand and one new strand

Positron Emission Tomography (PET scan)

involves injecting individuals with a mildly radioactive substance and monitoring changes in blood flow to different regions of the brain. Uses sugar consumption in cells as a basis to determine, used to determine if cancer has moved to nearby lymph nodes or tissues

Meiosis produce sperms cells through _________________ and egg cells through ______________

spermatogensis, oogenesis

Tetrad

structure containing 4 chromatids that forms during meiosis

Radiation

the movement of energy in waves or particles The shorter the wavelength, the more energy present

Conservative Replication

the parental molecule serves as a template for the synthesis of an entirely new molecule (after replication you have the exact same one that you started with)

Meiosis II

the second phase of meiosis consisting of chromatids separating, along with the two diploid cells splitting in two. Similar to mitosis, but the cells starting are haploid 2 haploid -> 4 haploid

Gene Expression

the series of events within a cell that takes the information within the DNA and produces the protein

Chemotherapy

the use of drugs to treat disease

Magnetic Resonance Imaging (MRI)

uses radio waves and magnets to generate detailed pictures of the body