Biology chapter 17
This presentation is the property of its rightful owner.
Sponsored Links
1 / 52

Biology Chapter 17 PowerPoint PPT Presentation


  • 83 Views
  • Uploaded on
  • Presentation posted in: General

Biology Chapter 17. Evolution : The History of Life. More than ______ of all species that have ever lived on Earth have become extinct. 99.9%. 17-1 The Fossil Record. I. Fossils and Ancient Life A. _______________ are scientists who study fossils.

Download Presentation

Biology Chapter 17

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Biology chapter 17

Biology Chapter 17

Evolution:

The History of Life

More than ______ of all species that have

ever lived on Earth have become extinct.

99.9%


17 1 the fossil record

17-1 The Fossil Record

I. Fossils and Ancient Life

A. _______________ are scientists who study fossils.

B. The fossil record _________ evidence about the history of life on Earth. It also shows how different __________ _____________, including species, have changed over time.

Paleontologists

provides

groups of

organisms


Ii how fossils form

II. How Fossils Form

remains of

the organism

A. For a fossil to form, either the _________ ___________ or some trace of its presence must be preserved.

1. A precise _________________ must be present to form a fossil.

2. The fossil record provides ____________ ____________ about the history of life.

set of conditions

incomplete

information


Biology chapter 17

sedimentary

rock.

B. Most fossils are formed in ___________ _______.

1. Sedimentary rock forms from the

_________________________________

2. These particles are carried by _________ ___________ into lakes or seas, where they eventually settle to the bottom.

erosion of rock into sand, silt, and clay.

streams

and rivers


Biology chapter 17

dead organisms may also sink to the

bottom

  • As layers of sediment build up over time, ________________________________

    _______ and become buried.

    4. If conditions are right, the ________ may be kept intact and free from decay.

  • The sediment gradually _____________

    _______

remains

compresses into

rock.


Biology chapter 17

Figure 17-2 Formation of a Fossil

Section 17-1

Water carries small rock particles to lakes and seas.

Dead organisms are buried by layers of sediment, which forms new rock.

The preserved remains may later be discovered and studied.

Go to Section:


Iii interpreting fossil evidence

III. Interpreting Fossil Evidence

age of fossils

A. Paleontologists determine the ________ _______ using two techniques:

1.Relative Dating

a. The age of the fossil is determined by ______________________ with that of fossils in other layers of rock.

b. Rock layers __________________ are generally ________ than those below it.

comparing its placement

nearer to the surface

younger


Relative dating

Relative Dating


Biology chapter 17

actual age

compare the relative age of fossils

c. Does not determine the ___________ of the rocks or the fossils.

d. Index fossils are used to ____________ ___________________. These fossils must be easily recognized and must have existed for a short period of time.


Biology chapter 17

radioactive decay of

elements in the rocks

2.Radioactive Dating

a. Based on the ___________________ ___________________.

b. Radioactive elements decay, ________ ______, at a steady rate which is measured in a unit called half-life.

c. Half-life: the length of time required for __________________________ in a sample to decay.

or break

down

half of the radioactive atoms


Biology chapter 17

natural clocks

d. Different radioactive elements have different half-lives and therefore provide ______________ that “tick” at ______________.

Example:

Carbon-14:half-life of about ______ ________

Potassium-40 : half-life of about ______ ___________

different rates

5,730

years

1.26

billion years


Biology chapter 17

taken up

they are alive

Carbon-14

e. Carbon-14 is _________ by living things while ______________. After an organism dies, the __________ in its body begins to decay to form ____________, which escapes into the air.

  • Carbon-14 has a relatively ____________,

    it is useful only for dating fossils younger than about ____________.

nitrogen-

14

short half-life

60,000 years


Carbon 14

Carbon-14


Radioactive decay

Radioactive Decay


Biology chapter 17

not intact

B. Most fossils are __________. Paleontologists must reconstruct an extinct species from a few fossil bits---remains of bone, a shell, leaves, or pollen.

http://www.colorado.edu/physics/2000/isotopes/radioactive_decay3.html


Biology chapter 17

Compare/Contrast Table

Section 17-1

Comparing Relative and Absolute Dating of Fossils

Relative Dating

Absolute Dating

Can determine

Is performed by

Drawbacks

Age of fossil with respect to another rock or fossil (that is, older or younger)

Age of a fossil in years

Comparing depth of a fossil’s source stratum to the position of a reference fossil or rock

Determining the relative amounts of a radioactive isotope and non-radioactive isotope in a specimen

Imprecision and limitations of age data

Difficulty of radio-assay laboratory methods

Go to Section:


Iv geologic time scale

IV. Geologic Time Scale

geologic

time scale

A. Scientists first developed the _________ _____________ by studying rock layers and index fossils worldwide. As geologists studied the fossil record, they found _______ ________ in the fossil animals and plants

_________________________. These times were used to mark the segments.

major

changes

at specific layers in the rock


Biology chapter 17

3

Precambrian and the present

Paleozoic Era

1. Eras: There are __ eras between the ___________________________.

a. ______________

b. ______________ (Age of Dinosaurs)

c. ______________ (Age of Mammals)

2. Periods: Eras are subdivided into ______.

Mesozoic Era

Cenozoic Era

periods


Biology chapter 17

Continental Drift


Plate boundaries

Plate Boundaries


San andreas fault

San Andreas Fault


17 2 earth s early history and 17 3 evolution of multicellular life

17-2 Earth’s Early History and 17-3 Evolution of Multicellular Life

4.6 bya....*___________________

*many sources of energy: volcanic activity, lightening, meteorites

*______________ in atmosphere: water vapor (H20), nitrogen (N2), and carbon dioxide (CO2), with only small amounts of hydrogen (H2) and carbon monoxide. The primitive atmosphere had little, if any, free _______.

no life forms present

poisonous gases

oxygen


Biology chapter 17

* intense UV (ultraviolet radiation) from sun

* In the presence of so much available energy, the primitive gases may have reacted with one another and produced small organic compounds, such as nucleotides and amino acids.


Biology chapter 17

bacteria evolve and inhabit most

environments

3.5 bya…*geological disturbances have calmed

*____________________________

_____________ (much like the bacteria of today and well adapted)


Biology chapter 17

cyanobacteria evolve

First organisms

2.2 bya....*____________________ and form mats in shallow seas. ________ ___________ to produce oxygen (02) via ______________

photosynthesis


Biology chapter 17

animal life abounds

1 bya....*algae and other water-borne photosynthetic organisms abound in the seas

* __________________ in the seas with many ______________________ like sponges, jellyfish and worms.

multicellular organisms

Green Algae

Brown Algae

Red Algae


A special note on the evolution of our atmosphere

A SPECIAL NOTE ON THE EVOLUTION OF OUR ATMOSPHERE:

Oxygen saturation

  • __________________ begins in the seas

  • ____________________________ (electrical storms split atmospheric water molecules releasing a single oxygen)

  • _______________________________ - (here single oxygen and regular oxygen unite to form O3 or ozone)

  • ___________________ stratosphere - ________ _____ most of the ________________. Life on land can now thrive under this protective ______ which begins 12-15 miles above the earth’s surface.

Oxygen moves into atmosphere

Oxygen reaches upper atmosphere

Ozone layer forms in

filtering

out

harmful UV rays

shield


Biology chapter 17

Paleozoic Era

550 mya.... “____________________” - the Cambrian Period records _____________ _______ of life in evolution’s history. Nearly all of the animal groups known today as well as a strange collection of animals that cannot be assigned to any living group of today appeared in a period of about 10 million years. This evidence is not based upon fossils.

the Cambrian Explosion

an unmatched

burst


Biology chapter 17

basing this new finding upon

molecular evidence

550 mya.... “the Cambrian Explosion”

Scientists are ________________________ ________________ of evolution found in the genes drawn from the living species of 16 animal groups. This has allowed scientists to estimate when all animals last shared a common ancestor with other forms of life. Although controversial, this evidence without the fossil “backup” is widely accepted by many scientists in the field today. If this finding holds up, the animal kingdom had __________________ ___________to develop than the fossils reveal.

hundreds of millions of

years longer


410 mya the

410 mya.....the “______________”

age of the fishes

Cartilaginous Fishes: Sharks, Skates and Rays


Bony fishes

Bony Fishes


Biology chapter 17

first land-based amphibians

360 mya...... ________________________ climb onto the land.


Amphibian frog

Amphibian: Frog


Biology chapter 17

primitive reptiles appear

  • 300 mya......______________________--the earth is now a large vegetated landmass with open plains, swamps and primitive trees. ____________ flourished in a tropical climate. Invertebrates flourished in the ocean. From these forests and swamps, of the so called “_____________” period, came the organic materials that ultimately formed our___________________.

Large insects

Carboniferous

fossil fuels of today


Coal forest carboniferous period 300 mya

Coal Forest “Carboniferous Period” (300 mya)


Biology chapter 17

a period of mass extinctions

where perhaps 95% of all life perished

  • 240 mya..._______________________ __________________________________ over a 100,000 year period. This was possibly due to a meteor impact. This occurred at the end of the_____________.

Paleozoic Era


Mesozoic era began 245 mya lasted 180 million years

Mesozoic Era: Began 245 myaLasted 180 million years


Reptiles lay eggs on land

Reptiles: Lay eggs on land

Bull Snake


Biology chapter 17

dinosaurs

first flowering plants

  • 205 mya.....beginning of the domination of ___________for 120 mya

  • 138 mya.....____________________ occur on land and the beginnings of tropical rain forests in some areas. The flowering plants spread and ultimately dominated the landscape through a period of 65 million years.


Biology chapter 17

an era of mass extinction that

ended the dinosaurs as well as 75% of all

plant and animal life.

  • 65 mya.....

    Meteorite activity is one explanation for this extinction. This occurred at the end of the_______________.

Mesozoic Era


Cenozoic era mammals spread out and began to dominate the landscape

Cenozoic Era: Mammals spread out and began to dominate the landscape.


Mammal chimpanzee

Mammal: Chimpanzee


Biology chapter 17

the earliest fossils of

intelligent

human

  • 100,000-200,00 years ago.......

    __________________ Homo sapiens date to about this time. Homo sapiens means “_________ __________” and modern humans are classified in this species.


17 4 overview

Unrelated

Related

Intense environmental pressure

Similar environments

Inter-relationshiops

Small populations

Different environments

Convergent evolution

Punctuated equilibrium

Adaptive radiation

Coevolution

Extinction

17-4 overview

Species

that are

form

in

under

under

in

in

can undergo

can undergo

can undergo

can undergo

can undergo

Go to Section:


Study guide 17 1

Study guide 17-1

1. Paleontologists

2. It is information about past life that is based on fossils.

3. It provides evidence about the history of life on Earth and how different groups of organisms, including species, have changed over time.

4. Extinct

5. False

6. B, D

7. Sediments settle to the bottom of lakes and seas ad bury dead organisms. The weight of upper layers of sediment compresses lower layers into rock and turns the dead organisms into fossils.

8. a) Relative dating b) Radioactive dating

9. A, B, D

10. False

11. True

12. Half-life

13. Radioactive dating

14. They measure the amount of remaining radioactive isotopes it contains. The smaller the amount, the older the sample.

15. False

16. Cenozoic, Mesozoic, Precambrian time, Tertiary, Jurassic, Carboniferous, Silurian, Cambrian

17. C

18. A, B

19. Eras and periods

20. Mesozoic Era

21. Cenozoic Era


Study guide 17 2

Study guide 17-2

1. a) Hydrogen Cyanide b) Carbon Dioxide c) Carbon Monoxide d) Nitrogen e) Hydrogen Sulfide f) Water

2. False

3. Spark simulating lightning storms

4. A, B

5. They are tiny bubbles, formed of large organic molecules, that have some characteristics of living cells.

6. False

7. Experiments show that small sequences of RNA could have formed and replicated on their own in the conditions present on early Earth.

8. DNA is a more stable information-storing molecule than RNA.

9. Microfossils

10. A

11. They produced oxygen, which first removed iron from the oceans and then accumulated in the atmosphere.

12. True

13. True

14. The first step was the evolution of internal cell membranes.

15. It proposes that eukaryotic cells arose from living communities formed by several organisms.

16. A,C,D

17. Sexual reproduction shuffles and reshuffles genes in each generation. This increase in genetic variation greatly increases the chances of evolutionary change due to natural selection.

18. False


Study guide 17 3

Study Guide 17-3

  • True

  • A,B,C

  • The animals were al soft-bodied

  • Cambrian

  • False

  • A,B,D

  • B

  • C

  • A

  • Devonian

  • Vast swampy forests of giant ferns and other plants that grew during that time formed thick deposits of sediment that changed into coal over million of years.

  • Mass extinction

  • False

  • Triassic, Jurassic, Cretaceous

  • Reptiles

  • Triassic

  • True

  • True

  • Reptiles

  • Their seeds are enclosed in a fruit, which protects the seed and aids in dispersing it to new locations.

  • More than half of all plant and animals groups were wiped out, including all of the dinosaurs.

  • True

  • Mammals

  • They were generally warm and mild.

  • First it cooled, causing a series of ice ages. The, it began to warm again.

  • False


Study guide17 4

Study guide17-4

  • Macroevolution

  • a.)extinction b.)Adaptive radiation c.)Convergent evolution d.)Coevolution e.)Punctuated equilibrium f.)changes in developmental genes

  • Possible causes include a huge asteroid striking Earth, many large volcanoes erupting, continents changing position, and sea levels changing.

  • The disappearance of so many species left habitats open. Often, the result was burst of evolution that produced many new species.

  • Adaptive evolution

  • The disappearance of the dinosaurs led to the adaptive radiation of mammals.

  • Convergent evolution

  • B

  • Coevolution

  • Plats have evolved poisons prevent insects from feeding on them. Insects, in turn, have evolved ways of inactivating or eliminating the poisons.

  • gradualism

  • it may occur when a small population becomes isolated or a small group migrates to a new environment. It may also occur following a mass extinction.

  • Punctuated equilibrium

  • True

  • Homologous hox genes establish body plans in animals that have not shared a common ancestor in hundreds of millions of years. In addition, major evolutionary changes may be based on hox genes.

  • True


Study guide vocabulary review

Study guide Vocabulary review

  • C

  • D

  • A

  • C

  • B

  • In coevolution, two species evolve in response to changes in each other over time.

  • Convergent evolution refers to the process by which unrelated organisms come to resemble one another as the evolve similar adaptations to similar environments.

  • Mass extinction is the occurrence of many extinctions around the same time.

  • Punctuated equilibrium is a pattern of macroevolution in which long, stable periods are interrupted by brief periods of rapid change.

  • In adaptive radiation, a single species, or a small group of species, evolves into diverse forms that live in different ways.


  • Login