Issues In Science Exam

The Big Bang Theory:

1. How old is the Universe, Earth

• about 13.8 billion years old, earth is about 4.54 billion years old.

• But The universe is infinitely old (or has no apparent age)

2. How big is the Universe

• 93 billion light years in diameter according to the portion of specific cosmos but whole universe is expanding indefinitely

3. Evidence for the Big Bang Theory

• the universe is constantly expanding

• Cosmic microwave background

• Abundance of light elements

4. Cosmic Microwave Background

• Faint leftover radiation from the big bang, it is the afterglow of the big bang, it is the surface of the “fog” energy that cleared when the universe became transparent

5. What is fine tuning for the Universe?

• it is constants and conditions in physics that are fine tuned to specific values to all the universe to be developed enough for life to be on it.

Lecture- Evolution:

1. What is evolution?

• gradual process of growth, change, or development from a simpler to a more complex form. Genetic traits change over generations, relying on natural selection

2. Darwin’s theory – describe

• states that all life evolves through a process called natural selection which includes overproduction, variation, competition, adaptation, and speciation.

3. What may be a reason for the evolution to happen? Example? So that a population can adapt to survive and reproduce in changing environments (natural selection). The peppered moth;s were light colored before the 1800s to match the trees but as the trees darkened they did too to survive. 

4. What is mutation in DNA?

• a permanent, unintended change in the sequence of letters (A, C, T, G) that make up your genetic code

5. What is natural selection?

• the process by which organisms better adapted to their environment tend to survive and produce more offspring

6. What is common descent for different species?

• an evolutionary concept describing how different species share a common ancestor from which they diverged over time

7. What kind of evidence we have for evolution? List it? Be able to describe them.

• Generics and Molecular Biology: Because all living things share the same universal genetic code, scientists can compare DNA and amino acid sequences. The more similar the DNA sequences between two species, the more closely related they are. 

• The fossil record: Fossils provide a physical timeline of life on Earth, documenting extinct species and how life-forms have changed over vast periods.

• Comparative Anatomy: Studying the physical structures of different species reveals evidence of shared ancestry. 

• Comparative Embryology: Comparing the early stages of development in different species reveals similarities that are not always visible in adult forms

• Biogeography: how species are distributed across the planet

• Direct observation: Evolutionary changes can also be observed directly, particularly in organisms with short life cycles.

8. What is radiometric dating? a technique used to determine the absolute age of rocks, fossils, and artifacts by measuring the decay of radioactive isotopes trapped within them. Absolute dating: same thing relative dating: the science of determining the sequential order of past events, objects, or fossils, without establishing their exact numerical age

9. What is Carbon 14 dating, how it works?  a scientific method used to determine the age of organic materials. By measuring the remaining amount of the radioactive isotope carbon-14 in a sample, scientists can calculate how long ago a plant or animal died.                       be able to calculate how old is fossil based on ratio of 14C/12C when you have half-life given. Similar to the one we did in the class.

10. What is important about sample collection when we use 14C dating? proper sample collection is critical because even microscopic amounts of carbon contamination can drastically skew the resulting age calculations

11. What can affect amount of 14C in the atmosphere? Cosmic rays, fossil fuels, nuclear testing, carbon exchange

12. What is half life time? the time required for half of a given quantity of a substance to decay, react, or be eliminated

13. What is radioisotope, isotope? A radioisotope is an unstable type of isotope that undergoes radioactive decay, releasing excess energy in the form of radiation to become stable. An isotope is an atom of the same chemical element that has the same number of protons but a different number of neutrons.

14. Give one example other than 14C – of the radioisotope used in radiometric dating: Potassium-40

15. How to choose which isotope to use? Selection is guided by whether the isotope is stable or radioactive, its half-life, and its abundance relative to other isotopes of the same element.

16. What is relative dating? Example? the science of determining the sequential order of past events, objects, or fossils, without establishing their exact numerical age. Cross cutting relationships.

Lecture – History of DNA

1. What did Griffith’s experiment show? proved that bacteria can transfer genetic information through a process called transformation.

2. What is DNA, RNA, protein. What is transcription, translation. Describe the way to go from DNA to protein. Be able to do a problem similar to the coding activity.

• DNA: It stores all of an organism's genetic information and is permanently locked inside the cell's nucleus.

• RNA: The messenger and worker molecule. It is a disposable copy of a specific DNA instruction that can safely leave the nucleus

• Protein: Proteins are the "workhorses" of the cell, making up structures, acting as enzymes, and regulating bodily functions

• Describe the way to go from DNA to protein. Be able to do a problem similar to the coding activity: Central Dogma of Molecular Biology. It involves two main steps: transcription (copying DNA into mRNA) and translation (reading the mRNA to build a chain of amino acids)

DNA: 

3. What makes a DNA a hereditary material? It has information storage, accurate replication, stable inheritance, and evolutionary mutability. How this material is carrier to the next generation? through specialized reproductive cells called gametes (sperm in males and eggs in females). What is DNA replication – very briefly describe it.: the biological process where a cell copies its genome before dividing

4. What can affect DNA? Describe main features of DNA. environmental factors, chemical exposures, and replication errors. Double helix, nucleotide building blocks, the four bases (A, T,G, and a C), complementary base pairing, organization, self replication.

5. Which bases are complementary in DNA. Thymine pairs with.. Thymine and Adenine, Cystosine and Guanine.

6. How big is a human genome? The human genome is approximately \(3.1\) billion base pairs long (haploid), translating to roughly \(6.2\) billion base pairs in most human cells (diploid)

7. Who discovered DNA structure? James Watson and Francis Crick

8. Why do we study DNA structure, properties? to understand the molecular blueprint of life. Understanding the double helix, hydrogen bonding, and polymer mechanics enables scientists to diagnose diseases, develop gene therapies, and advance biotechnology.

9. What is gene? the basic physical and functional unit of heredity, made up of specific sequences of DNA

Human Genome Project:

1. What is human genome project? an historic, international scientific research endeavor that successfully mapped and sequenced the entire human genetic code (the genome)

2. What was the reason to create the Human Genome Project? primary mission is to decipher the chemical sequence of the complete human genetic material

3. Who was a director of the Human Genome Project? Francis Collins

4. What causes genetic diseases? abnormalities in a person’s genetic material—DNA or chromosomes

5. How can you get a DNA mutation? two main ways: they can be inherited from your biological parents or acquired during your lifetime due to environmental factors or cell copying errors

6. Types of genetic testing: molecular, chromosomal, and biochemical

7. What are the benefits of genomics research for our health? shifting the focus from generalized treatments to precision medicine, early detection, breakthroughs, and gene therapy

8. Impact of genomics research on society: transforming modern healthcare through personalized medicine, accelerating drug development, and reshaping forensic science. also presents profound ethical, legal, and social challenges.

Ethics in Science

1. Give an example when ethical conflict in science can occur. the pursuit of knowledge clashes with moral values or societal well-being

2. What are Standards of Ethical Conduct in Science? the moral and professional guidelines that govern how research is conducted, ensuring the integrity of data, the safety of subjects, and public trust

3. What is research honesty? the ethical commitment to transparent, truthful, and unbiased practices across the entire research lifecycle

4. What is social responsibility of the researcher? the ethical and moral obligation to ensure that research benefits society while minimizing harm

5. What is Responsible conduct of research (RCR)? the practice of scientific investigation with integrity

6. What is included in RCR training? (list) includes core ethical topics, interactive discussions, and hands-on guidance on how to avoid research misconduct

Nuclear Energy

1. What is nuclear reaction? a process in which an atomic nucleus collides with another nucleus or a subatomic particle to form one or more new nuclides

2. Fusion: nuclear reaction that combines two light atoms into one heavier atom

3. Fission: nuclear reaction that splits a single heavy, unstable atom into two or more smaller ones.

4. radioactive decay: the spontaneous process by which an unstable atomic nucleus loses energy by emitting radiation

5. What isotope of U is used in nuclear plant? Uranium-235

6. What is uranium enrichment (overall)? the process of increasing the concentration of the isotope U-235 in natural uranium

7. How electricity is produced in Nuclear plant (overall): they generate electricity using heat to produce steam, which spins a turbine connected to an electricity generator

8. Do we have nuclear plants in TN? Yes, Tennessee has two major operating nuclear power plants, both owned and operated by the Tennessee Valley Authority (TVA). Together, these facilities generate about 45% of the electricity in the state

9. What was the Manhattan Project? Why it was created? was a top-secret U.S. government research and development program during World War II, it was created to make the world's first atomic bombs.