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![Page 1: CST Review](https://reader038.fdocuments.net/reader038/viewer/2022102609/56812f2c550346895d94be6e/html5/thumbnails/1.jpg)
CST
Review
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CST and FINAL EXAM REVIEW
Directions: Both your final exam and the CST (STAR) test are based on the California Standards. There are five major categories and they include: Investigation and Experimentation, Cell Biology, Genetics, Evolution and Ecology, and Physiology. Each of the categories includes a number of topics that you should know about. I am including each of the California Standards and questions that pertain to each. Answer them completely using your notes and textbook as resources.
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1. What is a controlled experiment?
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1.What is a controlled experiment?
Controlled experiment– tests effect of a single variable while keeping all other variables the same
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2. What is the difference between a hypothesis and a theory?
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2. What is the difference between a hypothesis and a theory?
hypothesis– a possible explanation to a scientific question. (an “educated guess” based on prior knowledge and observations)
Theory– a well tested and supported hypothesis (Cell theory, theory of Natural Selection, Atomic theory)
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Observation classified into two types:
Quantitative– involve numbers, counting, measuring objects.
Qualitative– involve characteristics that cannot be easily measured or counted such as
color or texture
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3. When conducting experiments, sometimes the results are not consistent and may yield results that are obviously wrong. What might be some typical sources of unavoidable errors?
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3. When conducting experiments, sometimes the results are not consistent and may yield results that are obviously wrong. What might be some typical sources of unavoidable errors?
•Human error (mistakes in conducting experiment)
•Small sample tested
•Contaminated sample
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4. Why is the cell membrane referred to as being semi-permeable?
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4. Why is the cell membrane referred to as being semi-permeable?
Most membranes are selectively permeable (some materials can pass across membrane and others cannot) like “sieve”
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5. The cell membrane can be referred to as a mosaic. What is the cell membrane composed of? (Draw a diagram and label)
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5. The cell membrane can be referred to as a mosaic. What is the cell membrane composed of? (Draw a diagram and label)
Proteins act like passageways for larger molecules to pass through membrane
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6. What is an enzyme and how does it speed up a chemical reaction?
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6. What is an enzyme and how does it speed up a chemical reaction?
Enzymes– specialized proteins that act as biological catalysts
(catalysts– a substance that speeds up rate of chemical reaction by lowering a reactions activation energy)
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Enzymes are very specific
Name of enzyme derived from reaction it catalyzes
Enzymes are not used up in a chemical reaction.
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7. What conditions affect the action of an enzyme (name three things)
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7. What conditions affect the action of an enzyme (name three things)
•Temperature
•pH
•Presence of substrate
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8. What is the difference between a prokaryotic and eukaryotic cell? (Give an example of each type)
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8. What is the difference between a prokaryotic and eukaryotic cell? (Give an example of each type)
Prokaryotic cell- no nucleus (bacteria)
Eucaryotic cell- has nucleus
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9. What are the roles of the endoplasmic reticulum and the golgi apparatus in the secretion of proteins?
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9. What are the roles of the endoplasmic reticulum and the golgi apparatus in the secretion of proteins?
Endoplasmic Reticulum- cell’s internal transport system (Rough ER- (has ribosomes attached) and Smooth ER (no ribosomes)
Golgi Apparatus- “post office” of the cell
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10. What is the role of mitochondria in the cell?
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10. What is the role of mitochondria in the cell?
Mitochondria- found in nearly all eukaryotic cells. Use energy from food to power growth, development and movement. Powerhouse of cell
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11. What kind of cells might have a high number of mitochondria?
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11. What kind of cells might have a high number of mitochondria?
Cells that need a lot of energy. Heart cells, sperm cells, muscle cells, etc.
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12. What are the four types of organic molecules found in living things?
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12. What are the four types of organic molecules found in living things?
Four groups of organic compounds found in living things (carbohydrates, lipids, nucleic acids, and proteins)
Macromolecules formed by process called polymerization (large compounds built be joining together smaller ones)
Monomers– smaller compounds
Polymers– large molecules
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13. Large macromolecules (polymers) are made (synthesized) from smaller building blocks called monomers. What are the building blocks for:
•Proteins-
•Carbohydrates-
•Nucleic Acids-
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13. Large macromolecules (polymers) are made (synthesized) from smaller building blocks called monomers. What are the building blocks for:
•Proteins- amino acids
•Carbohydrates- glucose (single-sugar, monosaccharide)
•Nucleic Acids- nucleotide
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14. Proteins are all made from amino acids. What makes one protein different from another?
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14. Proteins are all made from amino acids. What makes one protein different from another?
The number of amino acids and the sequence of amino acids (like letters in an alphabet spelling different words)
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15. What effect does temperature have on proteins?
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15. What effect does temperature have on proteins?
It changes the 3-dimensional structure of the protein (this will also change the way the protein functions)
Like when you cook a steak or eggs- it changes the consistency. It may also stop the action of an enzyme- snake venom
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16. What organelle is responsible for photosynthesis and what is the name of the chemical (pigment) responsible for capturing the energy from sunlight?
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16. What organelle is responsible for photosynthesis and what is the name of the chemical (pigment) responsible for capturing the energy from sunlight?
Chloroplasts- found in plants and some other organisms (none found in animals and fungi)
Green pigment- chlorophyll found in photosynthetic membranes
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17. What is mitosis and what types of cells undergo mitosis?
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17. What is mitosis and what types of cells undergo mitosis?
Division of cells forming two identical new daughter cells (body cells) 2n → 2n
Part of Cell Cycle
PMAT (stages) followed by cytokinesis
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18. What is the difference between diploid cells and haploid cells?
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18. What is the difference between diploid cells and haploid cells?
Diploid (2n)- two sets of chromosomes (normal number in body cells)
Haploid (n)- half the number of chromosomes (found in sex cells-gametes)
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19. What process produces diploid cells and which produces haploid cells?
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19. What process produces diploid cells and which produces haploid cells?
Mitosis- makes diploid cells 2n → 2n
Meiosis- makes haploid sex cells (gametes) 2n → n + n
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20. What is meiosis and what does it result in?
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20. What is meiosis and what does it result in?
Process of producing sex cells (gametes)
Results in four haploid (n) cells (sperm or egg)
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21. Explain why this is a good representation of fertilization: n + n =2n
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21. Explain why this is a good representation of fertilization: n + n =2n
Shows two haploid cells (gametes) coming together to produce diploid (2n) cell-zygote
n + n =2n
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22. What is meant by segregation when sex cells (gametes) are produced?
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22. What is meant be segregation when sex cells (gametes) are produced?
Chromosomes segregate (separate) during meiosis.
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23. What is independent assortment?
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23. What is independent assortment?
Each of the chromosome pairs separate independently of the others (like flipping a coin each time to determine which one to use)
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24. What is a mutation?
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24. What is a mutation?
Any change in an organisms DNA. Happens naturally and randomly
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25. Mutations may or may not affect the expression of a gene. Why?
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25. Mutations may or may not affect the expression of a gene. Why?
•It may not change the amino acid it codes for (there are multiple combinations that code for same amino acid)
•It may be a mutation in area of DNA that does not code for proteins
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26. What are sex chromosomes and what combinations would result in a boy or a girl?
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26. What are sex chromosomes and what combinations would result in a boy or a girl?
Girl = XX Boy = XY
23rd pair of chromosomes in humans
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27. What occurs during:
•Replication-
•Transcription-
•Translation-
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27. What occurs during:
•Replication- DNA making DNA
•Transcription- DNA making RNA
•Translation- RNA making Proteins
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28. What are the differences between DNA and RNA (name three)
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28. What are the differences between DNA and RNA (name three)
DNA RNA
Sugar-deoxyribose
Sugar-ribose
Double stranded
Single stranded
ATCG AUCG
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29. What is a codon and how is it involved in protein synthesis?
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29. What is a codon and how is it involved in protein synthesis? 3-letter code word on
mRNA that codes for a particular amino acid
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30. During replication, the DNA sequence of GTTACGCAT would result in another strand have a sequence of?
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30. During replication, the DNA sequence of GTTACGCAT would result in another strand have a sequence of?
GTTACGCAT
CAATGCGTA
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31. During transcription, the DNA sequence of GTTACGCAT would result in a strand of RNA having a sequence of?
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31. During transcription, the DNA sequence of GTTACGCAT would result in a strand of RNA having a sequence of?
GTTACGCAT
CAAUGCGUA
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32. Use the table below to determine what amino acid sequence the following strands of mRNA would code for:
•GGCAUACCC-
•UUCCAGUUA-
•GCATTACGG-
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32. Use the table below to determine what amino acid sequence the following strands of mRNA would code for:
•GGCAUACCC- Gly - Ile - Pro
•UUCCAGUUA- Phe - Stop - Leu
•GCAUUACGG- Ala - Leu - Arg
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What about a DNA sequence of:
•GGCATACCC-
•UUCCAGTTA-
•GCATTACGG-
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What about a DNA sequence of:
•GGCATACCC-
•CCGUAUGGG- Pro-Tyr-Pro
•UUCCAGTTA-
•AAGGUCAAU- Lys-Val-Asn
•GCATTACGG-
•CGUAAUGCC- Arg-Asn-Ala
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33. What are the complementary bases in DNA and in RNA?
•DNA-
•RNA-
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33. What are the complementary bases in DNA and in RNA?
•DNA- AT CG
•RNA- AU CG
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34. Males are more likely to have a sex-linked trait than females. Why?
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34. Males are more likely to have a sex-linked trait than females. Why?
Males only have a single X chromosome and will have recessive disorder on X chromosome automatically (do not have another X with a possible normal gene to counteract)
XHXh & XHXh- normal XhXh –disorder
XHY –normal XhY –disorder
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35. Why can a women be a carrier of a sex-linked genetic disorder but a male cannot?
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35. Why can a women be a carrier of a sex-linked genetic disorder but a male cannot?
Girls have 2 X chromosomes
XHXh- normal (carrier) carries the gene but does not express it
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35. What is crossing over? (Draw a diagram and explain)
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35. What is crossing over? (Draw a diagram and explain)
Legs of chromosomes cross over each other and exchange parts of themselves
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36. Complete the following genetic cross and give the genotypic and phenotypic ratios of the offspring: Tt x tt (draw punnett square and give ratios)
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36. Complete the following genetic cross and give the genotypic and phenotypic ratios of the offspring: Tt x tt (draw punnett square and give ratios)
Tt tt
Tt tt
T t
t
t
Genotypic ratio- 1:1
Phenotypic ratio- 1:1
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37. Complete the following genetic cross and give the genotypic and phenotypic ratios of the offspring: XXh x XhY (draw punnett square and give ratios)
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37. Complete the following genetic cross and give the genotypic and phenotypic ratios of the offspring: XXh x XhY (draw punnett square and give ratios)
XXh XhXh
XY XhY
X Xh
Xh
Y
Genotypic ratio- 1:1:1:1
Phenotypic ratio- 1:1:1:1Female-normal
Female-disorder
Male-normal
Male-disorder
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38. In fruit flies, the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is recessive. What are the possible combinations of genes in the offspring of two red-eyed heterozygous flies (Rr)? (draw punnett square)
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38. In fruit flies, the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is recessive. What are the possible combinations of genes in the offspring of two red-eyed heterozygous flies (Rr)? (draw punnett square)
RR Rr
Rr rr
R r
R
r
Genotypic ratio- 1:2:1
Phenotypic ratio- 3:1
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39. What is cloning?
![Page 89: CST Review](https://reader038.fdocuments.net/reader038/viewer/2022102609/56812f2c550346895d94be6e/html5/thumbnails/89.jpg)
39. What is cloning?
Cloning- a member of a population of genetically identical cells produced from a single cell
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40. What does biodiversity mean?
![Page 92: CST Review](https://reader038.fdocuments.net/reader038/viewer/2022102609/56812f2c550346895d94be6e/html5/thumbnails/92.jpg)
40. What does biodiversity mean?
Biodiversity- the variation and frequency of organisms within a given area
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41. How do alterations in a habit affect the biodiversity?
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41. How do alterations in a habitat affect the biodiversity?
Normally decreases the diversity. Human intervention, urbanization, habitat fragmentation and destruction
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42. What are biotic and abiotic factors that effect an environment?
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42. What are biotic and abiotic factors that effect an environment?
Biotic- all the living things in an environment (plant, animal, bacteria, etc.)Abiotic- non-living factors including temperature, precipitation (rainfall), soil type, etc.
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43. What are are the main trophic levels in a food chain or web? (Draw and label a diagram)
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43. What are are the main trophic levels in a food chain or web? (Draw and label a diagram)
Trophic level- individual level on food chain or food web. Always starts with producer (autotroph)
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44. What is always forms the base of a food chain or food web?
![Page 100: CST Review](https://reader038.fdocuments.net/reader038/viewer/2022102609/56812f2c550346895d94be6e/html5/thumbnails/100.jpg)
44. What is always forms the base of a food chain or food web?
Always a producer
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45. What are the four factors that affect a population size?
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45. What are the four factors that affect a population size?
Birth rate
Immigration
Death rate
Emigration
INCREASES POPULATION SIZE
DECREASES POPULATION SIZE
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46. What is ecological succession and what is the difference between primary and secondary succession?
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46. What is ecological succession and what is the difference between primary and secondary succession?
Series of events an environment goes through to regrow after a disturbance
Primary- starts with bare rock
Secondary- starts with soil
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47. What are biogeochemical cycles?
![Page 106: CST Review](https://reader038.fdocuments.net/reader038/viewer/2022102609/56812f2c550346895d94be6e/html5/thumbnails/106.jpg)
47. What are biogeochemical cycles?
cycling of nutrients (minerals and other chemicals) that sustain life. Three main cycles
Carbon cycle-
Nitrogen cycle-
Water cycle-
Phosphorus cycle-
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48. What are the two main processes that contribute to the oxygen and carbon cycles?
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48. What are the two main processes that contribute to the oxygen and carbon cycles?
Photosynthesis and Cellular Respiration
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49. What is an energy pyramid and what percent of energy is available to each succeeding trophic level?
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49. What is an energy pyramid and what percent of energy is available to each succeeding trophic level?
The movement of energy through an ecosystem.
Only 10% is available to each succeeding step
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50. What is carrying capacity?
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50. What is carrying capacity?
The maximum number of individuals an ecosystem can support
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51. How does the burning of fossil fuels and deforestation effect the environment?
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51. How does the burning of fossil fuels and deforestation effect the environment?
Burning fossil fuels = more CO2 (product of combustion)
Deforestation = more CO2 (trees not using CO2 for photosynthesis)
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52. Why are fungi and bacteria so important and helpful in preventing the Earth from being covered with dead organisms?
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52. Why are fungi and bacteria so important and helpful in preventing the Earth from being covered with dead organisms?
They are decomposers and return nutrients to the environment
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53. What is natural selection and why does natural selection act on phenotypes instead of genotypes?
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53. What is natural selection and why does natural selection act on phenotypes instead of genotypes?
Natural selection- process by which certain heritable traits—those that make it more likely for an organism to survive and successfully reproduce —become more common in a population over successive generations. It is a key mechanism of evolution.
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54. Define the following terms:
•Species-
•Population-
•Community-
•Biome-
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54. Define the following terms:
•Species- individual type of organism
•Population- group of same species in area
•Community- groups of different population in given area
•Biome- geographical region containing several ecosystems that have same climate and dominant communities (climax communities)
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55. What type of traits might give an individual a greater chance of surviving (fitness)?
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55. What type of traits might give an individual a greater chance of surviving (fitness)?
Those that make an organism more successful at getting food, mating, camouflage, etc
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56. What type of isolation might lead to the development of a new species?
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56. What type of isolation might lead to the development of a new species?
Geographic isolation- mountain ranges, rivers, oceans, etc.
Temporal isolation- timing of mating season
Behavioral isolation- different mating rituals
All three increase the chances that isolated groups will grow increasingly different and
eventually form a distinct new species
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57. Define the following terms:
•Behavioral selection-
•Disruptive selection-
•Stabilizing selection-
•Directional selection-
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57. Define the following terms:
•Behavioral selection-
•Disruptive selection-
•Stabilizing selection-
•Directional selection-
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58. What is genetic drift and when might it occur?
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58. What is genetic drift and when might it occur?
New population forms from small group of founders that might have limited gene pool.
May form when small number of individuals populate new island
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59. What is homeostasis?
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59. What is homeostasis?
Maintaining constant and stable internal conditions despite changes in the outside environment.
Works like a thermostat controlling room temperature
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60. How does a nerve impulse travel through the nervous system (describe an electrochemical impulse)
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60. How does a nerve impulse travel through the nervous system (describe an electrochemical impulse)
Part electrical and part chemical transmission of signal.
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61. What is a synapse and how does the impulse travel across the synapse?
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61. What is a synapse and how does the impulse travel across the synapse?
Synapse- gap between two neurons. Signal is carried by chemicals (neurotransmitters) across the gap
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62. What is a reflex arc?
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62. What is a reflex arc?
Reflex arc- when nerve impulse does not travel all the way to the brain first to respond to stimuli. Can react faster
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63. When you experience the “fight or flight” response, your adrenal glands secrete the hormone adrenaline. What is the result of this?
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63. When you experience the “fight or flight” response, your adrenal glands secrete the hormone adrenaline. What is the result of this?
You can react faster. Increased heart and breathing rate. Heightened senses
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64. What is a hormone?
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64. What is a hormone?
A chemical signal that is produced by endocrine glands. Include testosterone, adrenaline, growth hormone, etc.
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65. What is your body’s first line of defense against pathogens?
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65. What is your body’s first line of defense against pathogens?
sweat, skin, tears, mucus, stomach acid
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66. How does the HIV virus reduce you ability to fight off infections?
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66. How does the HIV virus reduce you ability to fight off infections?
The HIV virus attacks your body’s immune system. You are not able to fight off pathogens
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HIV targets the immune system
HIV- Human Immunodeficiency Virus
Retrovirus (contains RNA) that attacks andweakens the immune system
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Leads to “opportunistic” infections
HIV is transmitted by exchange of blood or other body fluids
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HIV reproduces in T-cells (cells that trigger immune responses)
HIV leads to AIDS (Acquired Immune Deficiency Syndrome)
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67. How does your circulatory and respiratory systems work together to maintain homeostasis?
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67. How does your circulatory and respiratory systems work together to maintain homeostasis?
Respiratory system takes in oxygen and releases carbon dioxide that it takes from you circulatory system.
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68. What endocrine gland and hormone it produces regulates metabolism?
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68. What endocrine gland and hormone it produces regulates metabolism?
Thyroid gland- The function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Every cell in the body depends upon thyroid hormones for regulation of their metabolism
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69. What important function do your kidneys perform to maintain homeostasis?
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69. What important function do your kidneys perform to maintain homeostasis?
Filter you blood and maintain fluid levels in bloodstream (blood pressure) and levels of salts, ph level, nitrogen wastes, etc.
Sends excess fluids to bladder to rid from body
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70. How does a vaccine provide you with immunity?
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70. How does a vaccine provide you with immunity?Vaccines artificially produce acquired immunity
1. Vaccine- substance that contains antigen of a pathogen 2. Causes immune system to produce
memory cells3. You can make antibodies right away if infected
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71. Where does chemical digestion of food begin?
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71. Where does chemical digestion of food begin?
In your mouth
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72. What type of pathogens do antibiotics work on or not work on?
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72. What type of pathogens do antibiotics work on or not work on?
Bacteria or fungi, but NOT on viruses
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73. What are your body’s non-specific defenses against pathogens?
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73. What are your body’s non-specific defenses against pathogens?
Inflammatory response- characterized by swelling, redness, pain, itching, and increased warmth at affected site
Reacts to every pathogen the same way
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74. What are your body’s specific defenses against pathogens?
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74. What are your body’s specific defenses against pathogens?Immune response is triggered when immune system detects a pathogen (2 types of immune response)
•Cell-mediated immunity- when lymphocytes (not antibodies) themselves defend the body.
•Humoral Immunity- also called antibody-mediated immunity
Antigens- protein markers on surfaces of cells and viruses that help immune system identify a foreign cell or virus
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75. What is an antibody?
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75. What is an antibody?Antibodies- proteins made by B-cells and destroy pathogens
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76. What is an antigen?
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76. What is an antigen?Antigens- protein markers on surfaces of cells and viruses that help immune system identify a foreign cell or virus
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77. What are the three types of neurons? (Diagram and label the correct pathway)
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77. What are the three types of neurons? (Diagram and label the correct pathway)
• Sensory neurons- detect stimuli and transmit signals to brain and spinal cord
• Interneurons- make up brain and spinal cord and receive and process information
• Motor neurons-pass messages from nervous system to organs and muscles
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78. What is a feedback loop and how is it similar to a thermostat in your house?
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78. What is a feedback loop and how is it similar to a thermostat in your house?
It operates by doing the opposite (negative) of what it senses. If senses it is to hot, it tries to cool down, to cold, tries to warm up.
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79. How are the nervous system and endocrine system similar? Different?
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79. How are the nervous system and endocrine system similar? Different?
Both regulate and control you body
Nervous system- fast acting and “hard wired”
Endocrine system- slower acting chemical signals carried in your bloodstream throughout the body. Control process that occur over long periods of time (hair growth, aging, sleep patterns, etc.)
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80. Why is a virus not considered a living thing?
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80. Why is a virus not considered a living thing?
It needs a host cell to reproduce (cannot reproduce by itself)