Bio 1001 Exam 1 Study Questions

**Chapter 1:** 1. Know the Definition of biology. the study of life 2. Know that biology is studied at levels from the largest scale (biosphere) to the smallest (the molecules and atoms that make individual organisms up). 3. What is the Biosphere = all the organisms on the earth and th...

**Chapter 1:** 1. Know the Definition of biology. the study of life 2. Know that biology is studied at levels from the largest scale (biosphere) to the smallest (the molecules and atoms that make individual organisms up). 3. What is the Biosphere = all the organisms on the earth and the physical environments they interact with. 4. Ecosystems all the organisms in an area plus their non-living physical environment 5. Organisms living things, one living thing is an organism 6. Organs and organ systems within an individual complex organism 7. Tissues muscle, connective, nervous, epithelial (lining) 8. Cells all living things are made up of one or more cells separated from their environment, and/or other cells, by a cell membrane 9. Organelles miniature organ-like structures (in that they perform specific functions for the cells they occur in 10. Molecules made up of two or more atoms 11. Atoms the smallest unit of an element. All atoms of the same element have the same number of protons, but isotopes of the same element have different numbers of neutrons 12. What are characteristics that we can use to tell a living thing, from a non-living thing? - I may ask multiple choice questions where you will have to recognize the 6 criteria - OR, there may be a question that asks you to come up with 3 or 4 of the 6 criteria I gave you 13. What is the difference between an autotrophic organism and a heterotrophic organism? - Autotrophic organisms that make their own food, mostly photosynthesizing organisms - Heterotrophic organisms that must consume other organisms (or their parts) to obtain energy 14. Broadly (generally) speaking, what are things that science can study? things that are observable or measureable, so supernatural things are outside of science - Why can't science study supernatural phenomena (things) 15. What must scientists do if past findings (hypotheses, theories) are proven to be inaccurate by new findings (new data, observations, new technology)? revise the hypothesis to accommodate the new data and test it 16. Know the basic framework used to answer questions using the scientific method. 17. What is an organic molecule? = they are molecules that contain the element carbon, also always contains hydrogen. The simplest organic compound is Methane (CH~4~) 18. What are the 4 types of biologically essential organic macromolecules? - 1\) carbohydrates - 2\) lipids (fats) - 3\) proteins (composed of chains of amino acids) - 4\) nucleic acids (DNA and RNA) 19. Know that the atoms that are part of a molecule, and the shape and size of a molecule and any charges of molecules within a molecule determine their function (how they interact with other molecules) 20. What is the smallest unit that can perform all the activities necessary to meet the definition of life? Answer Cells 21. Know that all organisms are made up of at least one cell. 22. What are the multicellular organisms? there are three types of multicellular organisms, they are all types of eukaryotes 1. Plants, 2) Fungi, 3) Animals 23. What is the function of the plasma membrane? it surrounds and defines each cell, separating it from the environment around it - The plasma membrane allows the cell to manage what comes in and goes out of the cell, it allows it to maintain homeostasis - What are things that limit how large cells can be? - The genome can only manage so much cytoplasm, if a cell gets too big its genes and their products (proteins) cannot efficiently maintain homeostasis. - As cells increase in size its cytoplasm (which contains everything within the cell) increases in volume at a rate faster than the plasma (cell) membrane increases. So, past a certain size the plasma membrane of a cell cannot manage things coming in and going out efficiently. - Some cells, like our voluntary muscles we use to move, can be very large in size. Muscle cells can be very large, because each on is made up of many muscle stem cells that fused together and so muscle cells have many nuclei. They also, usually, have long skinny shapes, which gives them more cell membrane surface area compared to the volume of what is inside their cells (cytoplasm). 24. What kind of molecules is the genetic information of a cell encoded (written) in? nucleic acids, DNA and RNA 25. What are key differences between prokaryotes (single celled organisms made up of a single prokaryotic cell) and eukaryotes (organisms made up of one or more eukaryotic cell)? 26. About how many organisms have biologists identified so far? More than 2 million 27. What do taxonomists use to visualize relationships between species? - Answer evolutionary trees 28. What are the three domains of life? Answer =....... 1. Bacteria, 2) archaea, 3) Eukaryotes 29. Which one to aimals, plants, protists and fungi belong to? 30. What are protists? usually single celled eukaryotes. Like amoebas, euglena, paramecia. - The very first eukaryotes were protists. Animals, plants and fungi each evolved from species of protists that had evolved into colonies of clones (genetic duplicates). In plants, animals and fungi their many identical cells have become integrated into a single organism and all the cells in each individual work together for the homeostasis of the organism - What is **homeostasis**? the process of maintaining the steady internal environments that organisms need for their life functions (metabolism) to function 31. What accounts for the unity (many shared characteristics, e.g. DNA) and diversity (millions of different types (species)) of living things on earth? - Answer: Biological Evolution over Millions of Years 32. What does the Tully Monster illustrate about the fossil record? it shows how unlikely fossilization is. It only lived in an ancient ocean covering Illinois about 300 million years ago. Nothing like it seems to have ever existed anywhere else in the world. 33. Biological evolution is the change occurring in species between generations. 34. How did artificial selection help Darwin recognize that natural selection was the explanation for the pattern of living things on the planet? it made him realize that the forces of nature can work in a similar way, with nature favoring some individuals over others, because their characteristics are better for that place and time. Over millions of generations the forces of nature have led to the evolution of millions of different species of living things 35. What did Darwin believe was the simplest explanation for the similarity, and differences, between tortoises and other organisms in different habitats on the Galapagos islands? 36. Hypothesis-driven science is mostly about explaining nature, what type of science is mostly about describing nature? observation science, not everything can be manipulated and experimented directly on, some things need to be observed systematically to learn about them **Chapter 2:** 1. What are the three physical states that matter can be found in? a. Solid b. Gas c. Liquid 2. An element is a substance that cannot be broken down into other substances by chemical reactions. 3. Which 4 elements make up about 96% of the weight of most cells?..... d. Carbon e. Oxygen f. Hydrogen g. Nitrogen 4. Know that a compound is a molecule that contains atoms of two or more elements in a fixed ratio. h. Examples of compounds include NaCl (table salt) and H~2~O (water) 5. Which two types of subatomic particles are found in the nucleus of an atom?..... i. Protons and neutrons j. NOTE: do not confuse the nucleus of an atom, with the nucleus of a eukaryotic cell 6. Atoms of the same element always have the same number of protons, but isotopes of the same element have different numbers of neutrons 7. Electrons are the third type of subatomic particle, they are located in "shells" (also called orbits) around the nucleus of an atom 8. What are the only subatomic particles that determine the chemical properties of an atom? k. Answer electrons, the electrons in the outermost shell (furthest from the nucleus of the atom) interact with those in the outermost shell of other atoms...these electrons are involved in chemical bonding 9. Chemical bonds hold atoms together to form molecules (which includes compounds), l. chemical bonds are the result of interactions between the outermost layer of electrons of the atoms involved 10. What is the strongest type of chemical bond? covalent bonds, in which atoms share electrons so each can fill their outer electron shells with electrons m. What type of electron interaction occurs to form this strongest type of chemical bond? 11. Water is a polar molecule (with slight positive charges around its hydrogen atoms and a slight negative charge near its oxygen molecule), because electrons are shared unevenly between the oxygen molecule and the two hydrogen atoms it is bonded to 12. What type of bonding do water molecules engage in with each other to make them "stick" together? they form hydrogen bonds, which are the result of the polar nature of water, with the oxygen end being slightly negative and the hydrogens being slightly positive. The oxygen atoms of water binds to hydrogen end of other water molecules 13. Know that chemical reactions involve interactions between reactants, which result in products. n. Chemical reactions involve the electrons in the outer most "shell" of atoms 14. Chemical reactions rearrange matter, but what two things can they not do? o. Answer 1) create matter, 2) destroy matter 15. About how long ago did the first life evolve on earth? 3.7-4 billion years ago 16. Where did the first life almost certainly evolve? oceans about 3.7-4 billion years ago 17. What are our cells mostly made up of? water 18. What compound accounts for most (66%) of our weight? water 19. What are the life supporting properties of life? i. Water molecules stick together. ii. Frozen water floats. why does frozen water float? iii. Resists temperature change iv. Water is a common solvent for life. 20. Why is the stickiness of water important for plants? it allows the transport of water up from the soil through the roots of a plant 21. Why is the fact that ice floats important to living things in bodies of waters that freeze? the ice on a pond insulates the water below, preventing it from freezing solid and killing animals in the pond 22. What are the two components of a solution? solvent and solutes 23. What is an aqueous solution? a solution in which the solvent is water 1. What is the main sugar in milk? lactose, a disaccharide made up of one glucose and one galactose molecule with a covalent chemical bond between them 2. What is the name of the enzyme that breaks down milk sugar? lactase 3. Normally mammals stop producing the enzyme to break down milk sugar after they stop nursing as they mature. Some humans have mutations that allow them to breakdown milk sugar throughout their lives, why has this unusual (for a mammal) ability evolved in some human populations? it evolved as humans started to domesticate other mammals and use their milk as food 4. In people that stop producing lactase (the enzyme that breaks down lactose (milk sugar)), where do these people (ones that stop producing lactase early in life) break down milk sugar? they break it down in their large intestine, with lactase produced by bacteria living in their large intestine 5. How many atoms can a carbon atom form covalent bonds with? a. Know that bonding with [ **four**] other atoms through covalent chemical bonds, allow Carbon atoms to form complex skeletons and macromolecules (big molecules) with many different functions in the metabolisms of cells. 6. Other than water, the cells of **[organisms]** (like us) are made up mostly of organic (carbon containing) compounds. Where does the carbon in our bodies ultimately come from? from the air and water. Carbon is taken from the environment by plants and algae and used to construct sugars through photosynthesis 7. What are polymers? a molecule made up of sub-units called monomers 8. What are the monomers of a polysaccharide? monosaccharides 9. What are the monomers of an proteins? amino acids 10. Organisms build organic macromolecules and break them down through digestion, b. Monomers of the macromolecules we digest can be used to construct other macromolecules. 11. The unique properties of organic compounds depend on two things, what are they? 1. its carbon **[\_skeleton\_,]** its size and shape and 2. the atoms attached to the skeleton as \_\_**[functional]**\_ groups. 12. What is the role of the functional group of an organic compound? gives it its specific characteristics, important to how works in chemical reactions 13. What is the chemical process that breaks down large organic macromolecules into their monomers? 14. What is the chemical process that connects monomers, like amino acids, into organic molecules, like polypeptides/proteins 15. \_\_**Carbohydrates**\_ include sugars and polymers of sugar, it is one of the 4 categories of organic macromolecules life depends on. 16. Which organic macromolecules are the primary source of dietary energy for animals? carbohydrates 17. What is the monomer used to construct cellulose by plants and eukaryotic algae? glucose 18. Which organisms make cellulose and where is it found within them? plants, cells walls and cellulose is mostly what wood is made out of 19. The simplest sugars, ones that cannot be broken down into smaller sugars, s are called what? monosaccharides 20. The monosaccharide [ **glucose**] is the main fuels to produce ATP to do energy requiring activities inside of cells. c. This monosaccharide is converted most efficiently into ATP through Cellular Respiration, which is an aerobic, \_**[Oxygen]** using, process. 21. A \_**[disaccharide,]** like lactose or sucrose, is made up of two monosaccharides 22. Sucrose is a disaccharide of one glucose molecule and one fructose molecule. d. What is the common name for sucrose? table sugar 23. What are polysaccharides? 24. Starch is a polysaccharide made up of **glucose** monomers, it is the main storage polysaccharide of plants. 25. What polymer of glucose is the polysaccharide animals use to store glucose to use as energy later? glycogen 26. What is the most abundant organic compound on earth? cellulose, which is a polymer of glucose used for structural purposes in plants 27. What are the monomers that proteins are made from? amino acids 28. Know the number and order of the 20 different types of amino acids animals use determines the three dimensional shape and function of a protein 29. What happens to the ability of a protein, like an enzyme, to do its job if its shape is changed? if its shape changes significantly, it becomes "de-natured", so its nature is destroyed, and it will either not work anymore or work poorly 30. Which category of organic macromolecules are steroids in? Lipids 31. Are all steroids "sex" hormones? no, there are steroids that are not sex hormones, like cortisol 1. What are the two concepts of cell theory? 1. All living organisms are composed of one or more cells. 2. Cells arise from pre-existing cells. 2. What are the two major categories of cells? Prokaryotes and Eukaryotes 3. How is the DNA in every cell organized? (Hint: we usually have 46 of them in each of our cells) DNA in the form or chromosomes. Each chromosome is made up of chromatin, chromatin is made up of DNA molecules and the protective proteins that DNA is wrapped around when it isn't being replicated for cell division or when genes aren't begin expressed (being used by a cell) 4. All cells have ribosomes, what is their function? ribosomes are the site of translation of an mRNA molecule made form a gene during transcription, into a protein 5. What is the cytosol of a cell? the fluid portion of the cytoplasm, mostly made up of water. 6. About when did the first prokaryotic organisms evolve? between 3.7 and 4 billion years ago 7. About when did the first eukaryotic organisms evolve? about 2.1 billion years ago, they evolved through the endosymbiosis of multiple prokaryotes (bacteria, and archaea) 8. What physically separates cells of all organisms? the cell membrane (also called the plasma membrane) 9. Which of the two major categories of cells are smaller and simpler than the other? prokaryotes 10. What is the cytoplasm of a eukaryote? everything inside the cell membrane, includes the gelatinous fluid and organelles 11. What types of organisms have chloroplasts and what is their function? plants and eukaryotic algae 12. What are some of the functions of proteins that are part of the plasma membrane? act as transporters to bring things in, or move them out of the cell. 3. Act as tunnels through the plasma membrane, allowing substances to diffusion either into a cell, or out of a cell. 4. They can act as cell identifiers = antigens 5. Act as enzymes 6. Act as receptors for signaling molecules, like hormones 13. Which polysaccharide, which has glucose monomers, makes up the cell walls of plant cells? 14. What allows materials to move in and out of the nucleus of a eukaryotic cell? pores (openings) in the double plasma membrane of the nucleus 15. Chromatin is made up of the DNA molecule that is a chromosome, plus what? histone proteins that they wrap around and protect DNA when it isn't being opened up to be replicated or a gene isn't being expressed 7. When a gene is being expressed, it means that its code is being turned into an mRNA molecule through transcription and then those mRNA molecules are used by ribosomes to construct a protein through translation 16. How many chromosomes does each human cell typically have? 46 17. What are enzymes? enzymes are biological catalysts that lower the activation energy of the metabolic chemical reactions they catalyze. 18. Which type of organic molecule are almost all enzymes? proteins 19. What would happen if something significantly changes the shape of an enzyme? it becomes denatured and doesn't function 20. Which two types of organelles act as cellular power stations? i. Chloroplasts the site of photosynthesis in plants and photosynthetic protists ii. Mitochondria present in all eukaryotic cells, the place where food molecules are ultimately turned into a high energy molecule that can do work in a cell..called Adenosine Triphosphate (ATP). 21. What is the ultimate source of all of the energy used by your cells? the sun, because we either eat plants and algae for energy, or we eat things that consume them 22. What does photosynthesis turn light energy into? glucose