Download Biology B Midterm I Review Name: Period: ____ Standard 1

Biology B Midterm I Review
Name: ____________________________ Period: ____
Standard 1: Genetics
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I can look at a genetics problem and determine the mode of inheritance based on the genotypes and
phenotypes of the parents and offspring. (Simple Dominance, Codominance, Incomplete Dominance, MultiAllelic and Sex-Linked).
Example Problems:
Determine the parental genotypes based on the phenotypes given and the mode of inheritance.
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Parents: Red, Green
Parental Genotypes: ____________
Offspring: Red (homozygous
Offspring Genotype: ________
Mode: ____________________________
Parents: Blue, Blue
Parental Genotypes: ____________
Offspring: Green
Offspring Genotype: ________
Mode: ____________________________
Parents: Blue, Red
Parental Genotypes: ____________
Offspring: Purple
Offspring Genotype: ________
Mode: ____________________________
Parents: Blue, Red
Parental Genotypes: ____________
Offspring: Striped
Offspring Genotype: ________
Mode: ____________________________
Parents: A Blood, B Blood
Parental Genotypes: ____________
Offspring: AB Blood
Offspring Genotype: ________
Mode: ____________________________
Parents: Bald, Hair (carrier)
Parental Genotypes: ____________
Offspring: Female Bald
Offspring Genotype: ________
Mode: ____________________________
Parents: Tall, Short
Offspring: Medium
Parental Genotypes: ____________
Offspring Genotype: ________
Mode: ____________________________
Parents: O Blood, B Blood
Offspring: O Blood, B Blood
Parental Genotypes: ____________ Offspring Genotype: ________
Mode: ____________________________
Parents: O Blood, B Blood
Offspring: O Blood, B Blood
Parental Genotypes: ____________
Offspring Genotype: ________
10. Parents: Normal Vision, Red Green Colorblind Offspring: Normal Vision
Parental Genotypes: ____________
Offspring Genotype: ________
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Mode: ____________________________
Mode: __________________________
I can complete a Punnett Square for Simple Dominance, Codominance and Incomplete Dominance recognizing
the difference in genotypes between these three types of inheritance patterns and how to analyze the results
using either ratios or percents.
Example Problems:
Sally has red moles and Johnny has white moles. Complete following three crosses. Note—each inheritance types
have different formats for genotypes:
1. If we assume that white moles are dominant to red moles. Cross Johnny with a homozygous Sally.
Genotypic Ratio: _______:________:________
Phenotypic Ratio: _______:________
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2. If we assume that red moles and white moles are codominant to each other. Complete the cross between Sally
and Johnny.
_________% Red
_________% ___________________
(Describe 3rd phenotype)
_________% White
3. If we assume that red moles and white moles are incompletely dominant to each other, complete the cross and
determine the hair color of their offspring:
_________% Red
_________% __________________
(Describe 3rd phenotype)
_________% White
Reflection:
Which types of inheritance patterns use genotypic and phenotypic ratios? ________________________
How is a genotype for simple dominance different than a genotype for incomplete/codominance?
Write a summary for the different type of inheritance patterns:
Simple
Codominant
Number of Phenotypes
Incomplete
Example Genotypes
What is happening?
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I can analyze a pedigree to determine the number of generations, gender and type of inheritance pattern
(dominant vs. recessive AND autosomal vs. sex-linked).
Pedigree #1
Pedigree #2
Answer the following questions based on the pedigree above:
1. How many generations are in pedigree #1? ______
2. How many generations are in pedigree #2? ______
3. How many girls are in pedigree #1? ______How many girls are affected with the trait in pedigree #2? _____
4. Is the trait in pedigree #1 dominant or recessive? ____________________
What evidence would you use to support your answer?
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5. Is the trait in pedigree #2 dominant or recessive? ____________________
What evidence would you use to support your answer?
6. Is the trait in pedigree #1 autosomal or sex-linked? ____________________
What evidence would you use to support your answer?
7. Is the trait in pedigree #2 autosomal or sex-linked? ____________________
What evidence would you use to support your answer?
Standard 2: Natural Selection and Evolutionary Forces
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I can identify and explain the four steps of natural selection from a scenario.
I can identify and graph the mode of natural selection that is occurring.
I can identify and explain if an adaptation is structural, physiological or behavioral.
I can identify and explain if the evolutionary force is abiotic or biotic.
I can identify which of the five evolutionary forces are driving evolution.
I can identify if the rate of evolution is following a gradualism or punctuated equilibrium path.
Scenario Practice #1
A buffalo grass plant sprouts in a small patch of soil in the eastern Wyoming plains; it ranges in height from short to
tall. It is a grass that is grazed on by large herbivores; therefore the tallest grasses are grazed on more often. If they
are grazed on too much they will suffer and die. However, because it doesn’t rain that much in Eastern Wyoming—
plants need to compete for water. The taller the plant the more extensive their root system is for getting water, if a
plant is too short, it’s roots will be shallow and not be able to compete for enough water and dry out when water is
scarce.
Identify Darwin’s Four Steps of Natural Selection
Organisms produce more offspring than can survive:
Variation exists within the population:
Beneficial variations help the organism survive and reproduce:
Overtime the beneficial variations make up the majority of the population:
Identify the mode of selection: _____________________Draw the graph: (label axis):
Is the adaptation being selected for structural, physiological or behavioral?
Is the evolution of buffalo grass being driven by an abiotic/biotic force? Please explain:
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Identify and explain which of the five evolutionary force(s) is driving evolution:
Based on the evolutionary force—do you expect the rate of evolution to be gradualism or punctuated equilibrium?
Explain your answer:
Scenario Practice #2
There are 13 types of Galapagos finches, also known as Darwin's Finches, and they share the same habits and
characteristics except for one, and they all have different beaks. The differences in their beaks might be the most
important aspect of their survival.
In 1977, a large drought affected the island in 1977, seeds became scarce. The finches vary in the beak size from small
to large. When the drought hit, many of the plant species died out and with them the smaller seeds. The only plants
which still produced seeds where the plants that produced large seeds that were drought resistant. Finches with
the largest, toughest beaks were able to eat larger seeds that weren't typically part of their diet and were able to
survive and reproduce.
Identify Darwin’s Four Steps of Natural Selection
Organisms produce more offspring than can survive:
Variation exists within the population:
Beneficial variations help the organism survive and reproduce:
Overtime the beneficial variations make up the majority of the population:
Identify the mode of selection: _____________________Draw the graph: (label axis):
Is the adaptation being selected for structural, physiological or behavioral?
Is the evolution of finch’s beaks being driven by an abiotic/biotic force? Please explain:
Identify and explain which of the five evolutionary force(s) is driving evolution:
Based on the evolutionary force—do you expect the rate of evolution to be gradualism or punctuated equilibrium?
Explain your answer:
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