Science 9Science 9

Unit A: Unit A: Biological DiversityBiological DiversityScience InActionScience InAction

Section 1.3: Pages 20-24Section 1.3: Pages 20-24Section 2.1: Pages 26-29Section 2.1: Pages 26-29

Lesson #3Lesson #3

Learner OutcomesLearner OutcomesI can I can identify the role of variation in species survival under identify the role of variation in species survival under

changing environmental conditions changing environmental conditions

I can describe examples of variation of characteristics within a I can describe examples of variation of characteristics within a species, and identify examples of both discrete and species, and identify examples of both discrete and

continuous variation continuous variation

I can distinguish those characteristics that are heritable from I can distinguish those characteristics that are heritable from those that are not heritable, and identify characteristics for those that are not heritable, and identify characteristics for

which heredity and environment may both play a role which heredity and environment may both play a role

What is What is VariationVariation?? VariabilityVariability within a species within a species

population.population.

Eg. Red/Blond Hair vs. Brown Eg. Red/Blond Hair vs. Brown HairHair

Eg. Blue eyes vs. Green eyesEg. Blue eyes vs. Green eyes

Examples of variability in include:

Red fox (color of coat) Antibiotic resistance

(bacteria) Banded snail (color and

design of shell)

Variation of Human Variation of Human Physical CharacteristicsPhysical Characteristics

Skin, eye, complexion Skin, eye, complexion colouringcolouring

Hair colour, baldnessHair colour, baldness

Supernumerary body Supernumerary body part (extra parts), or part (extra parts), or missing body partsmissing body parts

Cleft Lip and PalateCleft Lip and Palate

Variation of Human Variation of Human Physical CharacteristicsPhysical Characteristics

HeightHeight – average range – average range2.2. DwarfismDwarfism3.3. GigantismGigantism Blood typeBlood type- Groups A, B, AB, and O- Groups A, B, AB, and O SomatotypeSomatotype Dominance of Dominance of

handednesshandedness Dexterity and Dexterity and motor motor

skillsskills

Who is This Man?Who is This Man?

What is What is Natural SelectionNatural Selection?? Happens when factors in the environment Happens when factors in the environment

determines, or determines, or “selects”“selects” which individuals, which individuals, within a species, will be able to survive.within a species, will be able to survive.

Offspring will usually have Offspring will usually have similar similar adaptations adaptations for survival. for survival. WhalesWhales

Charles Darwin Charles Darwin – Theory of Evolution – – Theory of Evolution – “On the Origin of Species” book - 1859“On the Origin of Species” book - 1859

The 5 year voyage of the The 5 year voyage of the HMS BeagleHMS Beagle

Surveying and charting coastsSurveying and charting coasts

Antibiotic resistance is Antibiotic resistance is enhanced by natural selectionenhanced by natural selection

The top section represents a The top section represents a population of bacteria before population of bacteria before exposure to an antibiotic. exposure to an antibiotic.

The middle section shows the The middle section shows the population directly after exposure, population directly after exposure, the phase in which selection took the phase in which selection took place. place.

The last section shows the distribution The last section shows the distribution of resistance in a new generation of of resistance in a new generation of bacteria. bacteria.

The legend indicates the resistance The legend indicates the resistance levels of individuals.levels of individuals.

VariationsVariationsVa r ia t io n is one of the most critical

aspects of species survival. It may be: a g e n e t ic (cellular code) modification a b e h a v io r a l tendency

This enables some individuals within a species to s u r v iv e , while others, will p e r is h .

Genetic VariabilityGenetic Variability Species of Species of Side-blotched lizards Side-blotched lizards ((Uta Uta

stansburianastansburiana) in central California) in central California

Give it a TRY – Page 27Give it a TRY – Page 27 Survey the class and find how many people:Survey the class and find how many people:b)b) Can or cannot bend their thumb joint Can or cannot bend their thumb joint

“backward” without adding pressure“backward” without adding pressurec)c) Have earlobes that are attached or separateHave earlobes that are attached or separated)d) Have a pointed or smooth hairlineHave a pointed or smooth hairline

Draw a data table to record your results. Draw a data table to record your results. Create a graph that will best illustrate Create a graph that will best illustrate your resultsyour results

InheritanceInheritance Transmission of

characteristics from parents to offspring

The characteristics of The characteristics of the parents are the parents are carried to the next carried to the next generation by the generation by the process of process of heredityheredity

What are Non-Heritable Traits?What are Non-Heritable Traits?

Characteristics a r ea c q u ir e d and not necessarily passed on from generation to generation.

A t h le t ic is m , a r t is t ic a b ilit y ,

le a d e r s h ipqualities are all learned during the early years of life.

Continuous VariationContinuous Variation Variations are differences in characteristics Variations are differences in characteristics

that have a that have a multitude of variationsmultitude of variations, such , such as as heightheight, , shoe sizeshoe size, , arm length arm length etc…etc…

Discrete VariationsDiscrete Variations Discrete variations are differences in Discrete variations are differences in

characteristics that have a characteristics that have a definite definite formform. .

One characteristicOne characteristic, or the single, , or the single, other variation, of the characteristic.other variation, of the characteristic.

Either the organism Either the organism has a trait or has a trait or it does notit does not..

Example: Either your earlobes are Example: Either your earlobes are attached or they are not.attached or they are not.

Variation and the EnvironmentVariation and the Environment Some variations may be influenced

by interactions with the environment. These variations are n o tin h e r it e d .

: E x a m p le s in c lu d e

Change in the pigmentation of s k in c o lo r throughout the

seasons due to the sun.

H e ig h t a n d w e ig h t can be influenced by diet.

Give it a TRY – Page 29Give it a TRY – Page 29 Ready…………..set…………GO!!!!Ready…………..set…………GO!!!!

Quickly clasp your hands together above Quickly clasp your hands together above your head, interlocking your fingers.your head, interlocking your fingers.

Look to see which thumb is on top. Note which way Look to see which thumb is on top. Note which way feels more natural.feels more natural.

Finish the chart in your notes, indicating Finish the chart in your notes, indicating Left Thumb on Left Thumb on Top vs. Right Thumb on TopTop vs. Right Thumb on Top

Decide whether the data is discrete or continuous. Decide whether the data is discrete or continuous. Explain your answer. Explain your answer.

Is it Discrete or Continuous? Is it Discrete or Continuous? Page 29Page 29

Action Right Preference

Left Preference

Type (circle one)

Clasping Hands

Continuous

Discrete

Folding Arms Continuous

Discrete

Sample Multiple Choice Sample Multiple Choice QuestionsQuestions

1 .Q To better understand variation; scientists explore the characteristics, which are passed on from generation to generation within a species. Those characteristics that are passed on from generation to generation are …

. A g e n e t ic . B in h e r it e d . - C n o n in h e r it e d . - D n o n g e n e t ic

Sample Multiple Choice Sample Multiple Choice QuestionsQuestions

2 .Q An albino kangaroo is a kangaroo that is pure white. This characteristic is classified as a … . - A n o n in h e r it e d v a r ia t io n

. B c o n t in u o u s v a r ia t io n

. C d is c r e t e v a r ia t io n

. D s in g u la r v a r ia t io n

Sample Multiple Choice Sample Multiple Choice QuestionsQuestions

3 .Q Variations caused by interactions with the environment are not heritable. Plants that are grown in dim lighting conditions would turn out to be … . A id e n t ic a l t o t h e ir p a r e n t s

in a ll a s p e c t s. B m u c h lik e t h e ir p a r e n t s. C v e r y d if f e r e n t f r o m t h e ir

p a r e n t s. D s im ila r t o p a r e n t p la n t s

t h a t w e r e g r o w n in d im l ig h t

Sample Multiple Choice Sample Multiple Choice QuestionsQuestions

Q4.Q4. Cats Cats BB and and CC are similar in size, but cat are similar in size, but cat AA is taller when is taller when standing. Like humans, cats pass down genetic information standing. Like humans, cats pass down genetic information for height, but cats can mature to be a wide range of for height, but cats can mature to be a wide range of heights - it is not an "either/or" characteristic. The heights - it is not an "either/or" characteristic. The characteristic of height in cats can be described as a characteristic of height in cats can be described as a

C.C. non-heritable and continuous in variation non-heritable and continuous in variation D.D. heritable and discrete in variation heritable and discrete in variation E.E. heritable and continuous in variationheritable and continuous in variationF.F. non-heritable and discrete in variation non-heritable and discrete in variation

Answers to Previous Answers to Previous QuestionsQuestions

1.1. BB2.2. CC3.3. DD4.4. CC

Did you …Did you …… … identify the role of variation in species survival under identify the role of variation in species survival under

changing environmental conditions? changing environmental conditions?

… … describe examples of variation of characteristics within describe examples of variation of characteristics within a species, and identify examples of both discrete and a species, and identify examples of both discrete and

continuous variation?continuous variation?

… … distinguish those characteristics that are heritable distinguish those characteristics that are heritable from those that are not heritable, and identify from those that are not heritable, and identify

characteristics for which heredity and environment characteristics for which heredity and environment may both play a role?may both play a role?

HomeworkHomeworkReadRead pages 20-24, 26-29 pages 20-24, 26-29Check and Reflect Check and Reflect page 29, page 29,

#1-2, #5#1-2, #5UpdateUpdate Portfolio PortfolioReadRead pages 30-36 pages 30-36

Question 1Question 1 Give one example of a heritable Give one example of a heritable

characteristic and one example of a non-characteristic and one example of a non-heritable characteristic that we did not heritable characteristic that we did not discuss in class. discuss in class.

Heritable Heritable ____________________________________________________________________

Non-Heritable Non-Heritable ____________________________________________________________________

Question #2Question #2 What is discrete variation? What is discrete variation?

____________________________________________________________________________________________________________________________________________________________________________________________________________

What is continuous variation? What is continuous variation? ____________________________________________________________________________________________________________________________________________________________________________________________________________

Question #5Question #5 A scientist wants to study continuous A scientist wants to study continuous

variation in a mouse population. What variation in a mouse population. What mouse characteristics would she or he mouse characteristics would she or he investigate? investigate? __________________________________________________________________________________________________________________________________________________________________________ __________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________