Origin of Life Homework Packet
Assignment #1: Please complete the 19.3 Assessment Questions on page 558 of your text.
Assignment #2: Origins HW#2 (see pages 1-3 of your notes)
Assignment #3: Origins HW#3 (see pages 4-8 of your notes)
Assignment #4: Origins HW#4 (Miller – Urey: see page 6-7 of your notes)
Assignment #5: Origins HW#5 (see pages 9-13 of your notes)
Assignment #6: Please complete 18.3 Assessment Questions on page 528 of your text.
Assignment #7: Crossword Puzzle
KEY
Assignment #1:
1a. It was made up mainly of carbon dioxide, water vapor, and nitrogen and had little or no oxygen.
1b. In the environmental conditions of early Earth, simple compounds could have given rise to mixtures of organic compounds.
1c. Sample answer: Probably not because the same conditions no longer exist on Earth, and oxygen in the atmosphere would destroy organic molecules.
2a. A symbiotic relationship evolved between ancient eukaryotic cells and prokaryotic cells within them.
2b. Mitochondria evolved from endosymbiotic prokaryotes that were able to use oxygen to generate ATP
2c. Mitochondria and chloroplasts share many features of free living bacteria. They contain similar DNA and ribosomes. They also reproduce by binary fission.
3a. Sexual reproduction increases genetic variation, which gives natural selection more raw material to work on.
3b. Development of photosynthesis, free oxygen in the atmosphere, development of eukaryotic cells, sexual reproduction.
4. Sample answer: One RNA hypothesis suggests that RNA evolved before DNA. Under certain conditions, RNA molecules can help DNA replicate, catalyze chemical reactions, and replicate themselves. Therefore, it is likely that RNA existed before DNA. Scientists have not yet been able to show how RNA led to DNA- directed protein synthesis, and we may never know.
Biology CP Name
Origins HW#2 (correlates to notes packet pages 1-3)
KEY: 1) Nonliving Matter 2) Spontaneous Generation 3) Francesco Redi 4)Disproved 5)microscope 6)microorganisms
7)Spontaneously 8) Louis Pasteur 9) S- shaped 10)air 11) vital force 12) broth 13) organisms 14) Biogenesis
___A____15. Spontaneous generation is the hypothesis that life arises from:
a. nonliving materials c. living things
b. outer space d. DNA
16. Define biogenesis. The idea of life arising from Living organisms
17. Define abiogenesis. The idea that life can arise from nonliving material
18. Which two scientists were noted for their contributions in recognizing the importance of geological events on Earth setting up conditions that would play a major role in the evolution of life on Earth? Hutton and Lyell 19. Whose experiment helped to disprove spontaneous generation using meat in covered/uncovered jars with flies? Francesco Redi
20. How living things change over time is known as Evolution.
Biology CP Name
Origins HW#3 (correlates to notes packet pages 4-8)
___B____1. Stanley Miller and Harold Urey performed experiments to test:
a. Darwin’s theory of evolution
b. Oparin’s hypothesis of chemical evolution
c. Crick’s theory of cells
d. Redi’s theory of cells coming from other planets
___C____2. About how many years ago was the Earth cool enough to allow solid rocks to form and water to condense and fall as rain?
a. 100 b. 13.7 billion c. 4.2 billion d. 4.6 billion
3. What compounds were present in the earth’s early atmosphere? CO2, H20 (vapor), N2, CO, H2S, HCN
4. How was this different from today’s atmosphere? It didn’t contain almost any Oxygen
__A___5. Which hypothesis explains the formation of the seas?
a. Water vapor in the atmosphere condensed and fell to Earth as rain
b. An Asteroid hit Earth
c. the shifting of continents caused water to come from Earth’s core
d. Atmospheric hydrogen and nitrogen dissolved
___C____6. Large amounts of ultraviolet radiation reached the surface of early Earth due to
a. hydrogen in the atmosphwere
b. the size of the sun
c. the absence of an ozone layer
d. the lack of rainfall
___F_____7. True or False: Oxygen gas was abundant in primitive earth’s atmosphere.
___F_____8. True or False: Primitive earth was a very cold planet.
___T_____9. True or False: If you were transported back in time, you could not survive on primitive earth.
___F____10. True or False: Microspheres evolved from living cells.
11. What are proteinoid microspheres and what are their importance? Tiny bubbles formed from large organic molecules. Microspheres have some characteristics of living systems- they are precursors to cells (protocells). They have selectively permeable membranes and a simple means for storing and releasing energy (like cells do).
12. Why do scientists think that RNA may have evolved before DNA? Because some RNA sequences can help DNA replicate, some other RNA sequences catylyze chemical reactions and some RNA molecules are able to grow and replicate on their own.
13. Does Oparin's heterotroph hypothesis support abiogenesis or biogenesis? abiogenesis
14. Fill in the chart with information about early Earth and today’s Earth. Use terms from the list below.
brown oceans
blue skies
pinkish-orange skies
blue oceans
no life
many different life forms
about 20% oxygen
little to no oxygen
15. Put the following events in order (#1 first).
___2____Earth formed as pieces of cosmic debris collided with one another
___6____The earth cooled enough for solid rocks to form and water began to condense & fall as rain, leading eventually to the formation of permanent oceans.
____3___ The entire earth melted after being struck by one or more huge objects
____4___ Volcanic activity shook the earth's crust and comets and asteroids bombarded its surface
___1____Big Bang
___5____Heavier elements settled to the interior of the Earth; lighter elements remained at the surface
___T____16. True or False: Evidence suggests that life on earth originated approximately 4 billion years ago.
17. Fill in the missing blanks:
simple organic compounds --> large organic molecules --> protocells (microspheres)--> primitive cells
`
Biology CP Name ______________________________
Origins HW#4: Miller-Urey Experiment (see pages 6-7 of your notes)
1) The following is an illustration of the experiment conducted in the 1950’s by Stanley Miller and Harold Urey:
What was the purpose of the experiment? To see if mixtures of the organic compounds necessary for life could have arisen from simpler compounds on a primitive earth.
2) The apparatus above was meant to simulate the conditions of primitive Earth. What does each lettered part in the apparatus above represent?
A - Flask with boiling water _- oceans_________________________________________________________________
__________________________________________________________________________________________
B – Electric sparks- lightning __________________________________________________
__________________________________________________________________________________________
C - Cold Water collar- cold water cools the chamber causing droplets to form clouds
__________________________________________________________________________________________
D - Liquid moving down in inside of the collar ___rain_________________________________________________
__________________________________________________________________________________________
E -Water trap- collecting newly formed materials
_________________________________________________________________________________________
3) What types of materials were collected in the trap? _21 amino acids_
4) What was the conclusion of the experiment? _Simple organic compounds could be formed from gases present in the primitive atmosphere.
__________________________________________________________________________________________
5) The above apparatus was called a closed system because it was closed to the air in the lab room. Why was this necessary? To not let the oxygen inside the apparatus since primitive atmosphere contained little or no oxygen,
Biology CP Name ______________________________
Origins HW#5 (correlates to notes pages 9-13)
1) Define heterotroph. What is another term for heterotroph?
Organism that obtains food by consuming other organisms. Consumer.
2) Define autotroph. What is another term for autotroph?
Organism that is able to produce its own food from inorganic compounds. Producer.
3) What is the process by which most producers are able to make their own food? Photosynthesis
4) According to the heterotroph hypothesis, which group of organisms, producers or consumers, first inhabited the earth? _____ consumers . What were they feeding on?___organic matter_________
5) How did the formation of free oxygen from photosynthesis and the development of the ozone layer stop abiogenesis?
Ozone layer blocked UV radiation which was necessary for creating organic compounds from gases present in the primitive atmosphere.
6) ___A_____The organisms which are the ancestors of all life forms are:
a. Prokaryotes b. Eukaryotes
7) Place the following sequence of events in order from the first (1) to occur in the geological time scale to the last (10) to occur in time:
__6__ animals invade the land
_4___ multicellular eukaryotes form
__9__ the last dinosaurs reign
__1__ the first prokaryotes form
__10__ human development occurs
__5__ plants invade the land
__3__ unicellular eukaryotes evolved
__7__ first mammals are present
__8__ the first dinosaurs evolved
_2___ the first evidence of photosynthesis
____T____8) True or false: The ozone layer prevents much of the sun’s UV rays from striking earth today.
__b_____9. The structure labeled "X" in the diagram above is most likely a:
a. chloroplast b. mitochrondria c. nucleus
___A__ 10. Which of the following is evidence for the endosymbiotic theory?
a. Mitochondria and chloroplasts contain DNA similar to bacterial DNA.
b. Mitochondria and chloroplasts have similar functions in the cell.
c. Mitochondria and chloroplasts have no DNA of their own.
11. . How did sexual reproduction speed up the evolutionary process?
Sexual reproduction increases variation among members of a species. Increased genetic variation increases the likelihood of a population’s adapting to new environmental conditions. New and numerous adaptations will speed up evolutionary process.
12. Describe the likely characteristics of the first organisms on earth. Prokaryotic Heterotrophic, unicellular, anaerobic
___T_____13. True or false: The first cells on earth were prokaryotic.
_____14. Cells that cannot survive in the presence of oxygen are called:
a. eukaryotes b. autotrophs c. aerobes d. anaerobes
_____15. About 2.5 billion years ago, as autotrophs evolved and began releasing oxygen into the atmosphere, cells that could tolerate oxygen developed. They were the first:
a. heterotrophs b. aerobes c. anaerobes d. multicellular organisms
*Phrases and Word Bank are on the opposite side
Across
4. The evolution of new forms of life over millions of years is thought to be due to many many instances of sudden changes in DNA codes called Mutations
9. This team of scientists set up an apparatus designed to simulate the "primordial soup" thought to have been present on early earth MillerUrey
11. The idea that rotting meat creates flies is an example of "spontaneous Generation
12. The development of a protective Ozone layer in earth's atmosphere stopped the origin of new cells from nonliving materials.
13. The development of this process in some cells led to the addition of oxygen gas to earth's early atmosphere Photosynthesis
Down
1. The Endosymbiont theory is one idea as to how cells may have become eukaryotic
2. Were the first cells thought to be producers --or-- consumers?
3. The addition of Heat __?__ can cause all of the following: amino acids joining to form proteins; small organic molecules joining to form more complex molecules; amino acids joining to form protocells
5. Molecules such as proteins and nucleic acids are considered _ Organic molecules.
6. The term which describes complex cells, such as plants, animals, fungi and protists, which do contain a nucleus Eukaryotic
7. The oldest fossilized cells discovered so far are about 3.5 Billion years old.
8. The term which describes simple cells, such as bacteria, which do not contain a nucleus Prokaryotic
10. Scientist who performed an experiment involving raw meat, jars, and flies to disprove the idea of spontaneous generation Redi
13. The scientist who performed an experiment involving swan-neck flasks and broth to disprove the idea of spontaneous generation Pasteur
14. What gas, plentiful in Earth's atmosphere today, was thought to be absent from the atmosphere of early Earth? Oxygen