Evolution Web Activity

XBiologyChapters 14-15

(Visual Concepts)

Chapter 14 – History of LifeBiogenesis and Spontaneous Generation

1. Compare spontaneous generation (abiogenesis) to biogenesis.

– Spontaneous Generation/abiogenesis – living things can arise from non-living things

– Biogenesis – living things can only arise from other living things

Chapter 14 – History of LifeSpallanzani’s Experiment and Pasteur’s Experiment2. Complete the following table.

Scientist Experiment

Francesco Redi

Tested the theory of spontaneous generation - placed pieces of meat in two jars—one sealed and one open to the air. Maggots found only in the control jars that were open to air because that was the only place where adult flies could reach the meat to lay eggs.

Lazarro Spallanzani

Tested the theory of spontaneous generation- he boiled meat broth in flasks and then sealed some of the flasks and left others open to the air. The broth in the open flasks became cloudy, while the broth in the sealed flasks remained clear.

Louis Pasteur

Disproved the theory of spontaneous generation of microorganisms - curved-neck flasks did not allow microorganisms to contaminate the broth even though the flasks were open to the air. When the necks were broken off, microorganisms were able to reach the broth, which became cloudy and contaminated.

Redi’s Experiment

Spallanzani’s Experiment

Pasteur’s Experiment

Chapter 14 – History of LifeRadiometric Dating (also Half Life)

3. What is the radioactive isotope of carbon?14What is its half life?5, 715 yearsA student is told that her fossil contains ¼ the amount of Carbon-14 that it originally had. How old is the fossil?2 x 5,715 years = 11,430 years old

Chapter 14 – History of LifeOrigin of Eukaryotic Cells

4. How do scientists believe mitochondria and chloroplasts evolved? Prokaryotic cells that entered large prokaryotic cellsGive one similarity that both share with prokaryotic cells.

Circular DNA, divide like bacteria

Chapter 14 – History of LifeEndosymbiosis

5. What is endosymbiosis?A mutually beneficial relationship in which one organism lives inside another

6. According to the endosymbiont theory, eukaryotic cells evolved when a relationship developed between a small prokaryotic cell that lives inside of a larger prokaryotic cell.

Chapter 15 – Theory of EvolutionEvolution and Mass Extinction

7. What are some causes of mass extinctions? How many have there been in Earth’s history?Drastic changes in the environment

• How many years ago was the extinction of the dinosaurs? What is thought to have caused this?65 million years ago (mya)Drastic changes caused by asteroids colliding with the Earth caused dust to blacken the sun and the temperature dropped

9. What is causing the latest mass extinction? What is so remarkable about this compared to the previous extinctions?Human activity. Species are disappearing faster than ever before

Chapter 15 – Theory of EvolutionLamarck’s Theory of Evolution

10.What correct thoughts did Lamarck have about evolution?1) Types of organisms change over time2) New types of organisms are modified descendants of older types

What incorrect thoughts did Lamarck have?Traits were acquired through an organism’s experience or behavior and could be passed onto offspring. NOT TRUE…acquired characteristics are NOT inherited.

Chapter 15 – Theory of EvolutionDarwin’s Theories and Natural Selection

11.What was the nameof Darwin’s ship that he sailed on?HMS Beagle

12.Briefly describe Darwin’s two main ideas about evolution:

• Descent with Modification – newer species are modified descendants of older species

• Natural Selection – organisms best adapted to their environment are more likely to survive and reproduce

Natural Selection

Chapter 15 – Theory of EvolutionAdaptation

13. Define evolution.Process by which populations change over time

14. Explain why a drought on the Galapagos Islands led to an increase of larger finches with larger beaks.A drought could cause small, soft seeds to disappear leaving only large seeds. Larger finches with larger beaks could eat more and survive longer reproducing offspring with larger beaks more suited for their environment. The finches with small beaks could not eat the large seeds and died before producing more small beaked birds (Competition for resources)Which of Darwin’s ideas is this a result of?Natural selection

Chapter 15 – Theory of EvolutionAdaptation continued

15.Explain how the beaks of each of the finches listed below are adapted to their food sources. (Finches were all descendants of a common ancestor finch).

Finch Beak Food Source

Ground Large & Heavy Thick, hard seeds

Cactus Tough & Like Needle-Nose Pliers

Catus & insects

Warbler Small & Pointed (like tweezers)

Insects in cracks & crevices

Chapter 15 – Theory of EvolutionFitness

16.Define fitness.The ability of an organism to survive longer and reproduce more

17.Using the insecticide example for fitness, explain how the use of antibacterial soap and “hand sanitizers” might be a bad idea.Bacteria that are resistant will survive and reproduce creating a population of only resistant bacteria. Hand sanitizers will then be useless against them.

Chapter 15 – Theory of EvolutionLaw of Superposition

18.What is the law of superposition?The lower the rock layer, the older the fossil

19.List the layers from oldest youngest (most recent) in the diagram in this section.Oldest = A, then B, then C, then D (D is the youngest)

Age of Fossils

Chapter 15 – Theory of EvolutionGeologic Time Scale

20.How old is the Earth?4.6 billion years old (byo)

21.What are eras defined by? Type of animal presentThe end of an era is defined by what?Extinction of those animals

22.What era are we currently in? CenozoicPeriod? QuaternaryEpoch? Holocene

Chapter 15 – Theory of EvolutionHomologous Structures

23.Why is a human arm and the wing of a bat considered to be homologous?They have similar structures but with different functions

Chapter 15 – Theory of EvolutionAnalogous Structures

24.Why are the wings of bees and the wings of birds considered to be analogous?They have similar function but different structure (therefore, not related)What are analogous structures a result of?Convergent evolution

25.Complete the following statement:Homologous structures have similar structure but different functions, whereas analogous structures have different structure but similar function.

Chapter 15 – Theory of EvolutionVestigial Features

26.What is a vestigial structure? Give an example.Features that have no function, but genetically link us to animals who have a function for these structuresExamples: tail bone, third eyelid, appendix

Chapter 15 – Theory of EvolutionSimilarities in Embryology

27.How are early stages of vertebrate embryological development evidence of a common ancestor?Because they are so similar to one another; shows a common genetic blueprint (common ancestry)

Chapter 15 – Theory of EvolutionSimilarities in Macromolecules

28.How are macromolecules used as evidence for evolution?1) DNA similarities2) Fossil evidence3) Homologous structures4) Embryonic similarities