Evolutionary Spandrels

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Read the article by Gould and Lewontin (1979).  This article presents a  critique of the way evolutionary biology was evaluating selection and  adaptation. This article spawned a major turning point for the field.   It provides the notion that some traits arise simply as a structural  byproduct of selection on other traits. This means that observed or  inferred functional differences cannot always be equated to adaptive  changes.
After reading this article, write a short essay describing how this idea  of constraints impact evolution and the way in which researchers should  study evolution. What information would Gould and Lewontin need to  justify calling a trait an adaptation? What are the main critiques of  the Adaptationist Programme? How important do you think the evolutionary  history of the species is when considering if a trait is an adaptation?  How important do you think constraints are to the process of evolution?  Explain your reasoning for these opinions. Be sure to relate back to  the readings, lectures, and/or videos that you watched in Modules 2 and  3.
Requirements
One-half to one typed-page, single-spaced, times new roman, and 12 point  font.  DO NOT GO OVER ONE PAGE.  Include your name and your section  number at the top of the page and upload your assignment as a Word  document by the due date. Be concise and logical in your writing

 
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Ted Talk- Biology 2

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December

http://ed.ted.com/on/4Po9AliB

1- In two paragraphs list and describe the major steps involved in photosynthesis.

http://ed.ted.com/on/Hpqpcgn9

1- The Calvin cycle is the second part of the photosynthesis reaction. Photosynthesis stores energy from the sun and carbon from the air together in the high-energy molecule, glucose. Like any factory the Calvin cycle needs energy to create glucose. Where does this energy come from?
2- Rubisco makes up about 15% of the total protein in a chloroplast. Why might chloroplasts have evolved to have so much of this one enzyme?
3- In addition to being highly abundant in chloroplasts, Rubisco is the most abundant enzyme on the planet. Why is Rubisco the most abundant enzyme and why is this important?
4- Temperature and light intensity are two factors that affect the rate of photosynthesis. Which of these factors would you expect to have the greatest effect on the rate at which the Calvin cycle proceeds, and why?
5- Many significant areas of our planet are becoming less green and more areas are being built on (desertification, urbanization, industrialization). More and more areas of the planet are losing their capacity to support plant life. What risks are we facing by making our planet less green? And what can we do to help make our planet more green?
http://ed.ted.com/on/3mPgW5dj
1- How do phytochromes work within the plant cell?
2- What is more important when a plant is deciding when to create blooming flowers: the time of day or the season of the year? Why?
3- Circadian rhythms are especially important in the beginning of a plant’s life. Until their phytochromes perceive the presence of light, seed sprouts grow tall and long, and do not produce any green pigment. As soon as they reach light, they begin to produce green pigment and broader leaves. What are the advantages of producing green pigment only after the presence of light?
http://ed.ted.com/on/SLIWfji1
1- Do you eat organic food? Why? or Why not?
2- Have you ever thought about the world through the perspective of a crop or a farmed animal? What conclusions did you come up with?
3- Do some research. What is the most abundant plant on the planet? How did this happen?
http://ed.ted.com/on/c8aTM4Et
1- Humans have cut and frayed the woven tapestry of Earth’s biodiversity. List and describe three ways Humans have negatively impacted biodiversity.
2- Correctly use the following words in a well-written, scientifically correct paragraph. Be sure to clearly distinguish the differences between each of them and how they intertwine! Be sure to provide examples. Species diversity, biological diversity, ecosystem diversity, genetic diversity.
http://ed.ted.com/on/lX2ej6c6
1- Think about your own home or school and identify the sources of “throwaway” plastic. Which of these could be easily eliminated, if any?
2- According to Moore, why is it impossible to obtain certified organic wild-caught fish?

http://ed.ted.com/on/YGOqhnPB

1. Take some time to read and research some great information about vitamins in the dig deeper section and answer this question- Do we need to take vitamin supplements for optimal health or are we wasting money on vitamin pills? In a 2-3 paragraphs explain if and when a person might need a vitamin supplement and when it might be a waste of money or even be harmful to your health.

1. At the bottom of the dig deeper section there is a link to a cool graphic from information is beautiful. Discover the scientific evidence for popular dietary supplements and Describe 5 supplements that might improve your health and vitality.
http://ed.ted.com/on/Y0RNnPVf
1. The American diet is said to be increasingly energy-rich but nutrient-poor. Use the links you find in the Dig Deeper section to type a complete paragraph on how a person can be overweight but undernourished, and how going back to the basics with nutrient dense foods can improve the health of many Americans.
 
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Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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4/28/2020 Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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Bio U7 Practice Test 1 A

1.

2.

Which of these point mutations to DNA triplet CGG would affect the protein made?

A lone wolf travels hundreds of miles from his original pack and joins a new pack in a different range, affecting the gene pool through which mechanism?

CGA

CGT

TGG

AGG

recombination of alleles

genetic drift

no effect

gene flow

 

 

4/28/2020 Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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3.

4.

5.

6.

Which of these correctly shows ecological succession in a lava field?

Bob has red hair. Where is the genetic code for red hair found?

In primroses, red, the dominant flower color, has incomplete dominance or intermediate expression. What will happen to the offspring if a heterozygous red primrose is bred with a homozygous white primrose? White is recessive.

A palm tree’s roots grow downward to the water source and anchor the tree so it is not easily uprooted by the wind. The roots growing downward is what type of plant response?

Soil is created. Moss and lichen arrive by birds to barren lava field. Fountain grass grows. Monkeypod trees grow.

Moss and lichen arrive by birds to barren lava field. Soil is created. Fountain grass grows. Monkeypod trees grow.

Moss and lichen arrive by birds to barren lava field. Fountain grass grows. Monkeypod trees grow. Soil is created.

Soil is created. Moss and lichen arrive by birds to barren lava field. Monkeypod trees grow. Fountain grass grows.

tRNA in the cytoplasm

DNA in the nucleus

in the mRNA in the ribosomes

the proteins assembled by the ribosomes

100% will be pink.

100% will be white.

50% will be red; 50% will be pink.

50% will be pink; 50% will be white.

photoperiodism

photosynthesis

phototropism

geotropism

 

 

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7.

8.

9.

How would deforestation in the Amazon affect the carbon cycle?

An ivy is placed on a counter. The vines begin to grow toward a window. What plant response causes this?

Transcription occurs in which organelle?

Carbon in biomass stays the same.

Carbon in biomass increases.

Atmospheric carbon increases.

Atmospheric carbon decreases.

photoperiodism

phototropism

photosynthesis

geotropism

nucleus

mitochondrion

ribosome

chloroplast

 

 

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10.

11.

Which of these molecules represents a protein?

Howard looks at a sample of pond water in the microscope. He sees cyanobacteria and plasmodium, a type of protist. What is one difference between the plasmodium and the cyanobacteria?

The plasmodium has a nuclear membrane.

The cyanobacteria is unicellular.

The cyanobacteria has a nuclear membrane.

The plasmodium is unicellular.

 

 

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12.

13.

14.

15.

A lizard in a desert is colored brown to match the color of the sand. A few lizards have an adaptation that makes their top half blue. A new shrub with blue flowers is introduced to the desert. What is likely to occur in future generations?

In field mice, brown fur is dominant and white fur is recessive. If a field mouse that is heterozygous for brown fur breeds with a field mouse that is homozygous for white fur, what is the probability that their offspring will have white fur?

Every tRNA has an anticodon. What is the purpose of an anticodon?

A human baby weighs 8 pounds at birth and 150 pounds as an adult. Which statement is true about the person’s growth?

The population of brown and blue lizards will stay the same.

The population of brown lizards will increase.

All the brown lizards will die out and only blue lizards will be left.

The population of blue lizards will increase as they can use the flower for shelter and camouflage.

100%

75%

25%

50%

Anticodons tell the tRNA when to begin retrieving amino acids.

Anticodons help the tRNA retrieve the correct amino acid.

Anticodons tell the tRNA when to stop retrieving amino acids.

Anticodons help the tRNA retrieve the correct nucleic acid.

The number of cells increased because of mitosis.

The cells grew bigger during the G1 and G2 growth phases.

The cells grew bigger as the person developed.

The number of cells increased because of meiosis.

 

 

4/28/2020 Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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16.

17.

18.

19.

The zebra mussel is an invasive species. Which statement is most likely true if the zebra mussel is introduced to a new environment without predators?

Proteins are assembled on which part of the cell?

This type of cell can develop into different types of blood cells in a body.

A Pacific island receives a large quantity of precipitation. This enables bacteria to grow and reproduce rapidly. What is true of an island in the tropics?

Zebra mussels will disrupt the community and cause native species to decline as they eat all the food.

Zebra mussels will not cause a significant change in the community.

Zebra mussels will become the keystone species.

Zebra mussels will become part of the climax community.

smooth ER

rough ER

Golgi apparatus

nucleus

pluripotent stem cell

totipotent stem cell

ectoderm

multipotent stem cell

The bacteria eat oil in an oil spill.

People are more easily infected with bacterial disease.

Decomposition of a dead mouse occurs rapidly.

Bacteria are in competition with fungi.

 

 

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20.

21.

22.

23.

Fossils of whales and whale ancestors show a change in species over time. The ancestral species are no longer in existence. What type of evolution most likely occurred with whales?

A golf course is next to a river. The fertilizers they use for the golf course get washed into the river. What might happen as a result of the excess fertilizer?

What is the name of the organization level that is missing from this picture?

A runner uses all available oxygen for respiration. She then notices that her legs are becoming sore. Which of these statements is most representative of respiration?

equilibrium

punctuated gradualism

punctuated equilibrium

gradualism

The water warms due to excess nitrogen.

Fish die due to algae blooms.

Nitrogen-fixing bacteria die off.

Fish die due to nitrogen-fixing bacteria.

organelle

tissue

cell

organ

Her body is producing lactic acid because she is breathing too hard.

Her body is producing lactic acid as a result of doing aerobic respiration.

She has been running too long.

Her body is producing lactic acid as a result of doing anaerobic respiration.

 

 

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24. What type of molecule is shown in the picture?

amino acid

nucleic acid

RNA

DNA

 

 

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25. Which two species are the most closely related?

guinea pig and rabbit

tree shrew and manatee

duck-billed platypus and elephant shrew

lemur and bonobo

 

 

4/28/2020 Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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26.

27.

Look at the cross-section of a woody stem. Where is the xylem tissue located?

Cockroaches have low genetic diversity, yet are in no danger of going extinct. Which statement is most correct about the reproductive success of cockroaches?

only in the roots and not shown in the picture

toward the outside of the stem

throughout the stem

toward the center of the stem

Cockroaches have adaptations to be able to live in any environment.

Cockroaches have adaptations that allow for interbreeding without any harm.

Cockroaches have evolved to be generalists.

Cockroaches are the “fittest” of all beetles.

 

 

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28. Identify Creature X using the dichotomous key.

Creature X

Creature Y

 

 

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1 – a. Organism has a small head – go to 2 b. Organism has a large head – go to 3

2 – a. Organism has a narrow body – go to 6 b. Organism has a round body – go to 7

3 – a. Organism has a narrow body – go to 4 b. Organism has a round body – go to 5

4 – a. Organism has a curly antennae – go to 9 b. Organism has a straight antennae – go to 17

5 – a. Organism has short arms – go to 18 b. Organism has long arms – go to 19

6 – a. Organism has a curly antennae – go to 11 b. Organism has a straight antennae – go to 12

7 – a. Organism has a curly antennae – Roundus tricurlus b. Organism has a straight antennae – go to 8

8 – a. Organism has spots – Roundus trispottis b. Organism has no spots – Roundus squintus

9 -“ a. Organism has round eyes – Narrowus trifurrus b. Organism has narrow eyes – go to 16

10 – a. Organism has round eyes – Roundus diheadfuzzus b. Organism has narrow eyes – Roundus difuzzus

11 – a. Organism has round eyes – go to 15 b. Organism has narrow eyes – Narrowus trispottis

12 – a. Organism has short arms – go to 13 b. Organism has long arms – go to 14

13 – a. Organism has fur – Narrowus difuzzus b. Organism has no fur – Narrowus bareus

14 – a. Organism has spots – Narrowus longspottis b. Organism has no spots – Narrowus tippus

15 – a. Organism has a tail – Narrowus trifuzzus b. Organism has no tail – Narrowus quadspottis

16 – a. Organism has two feet – Narrowus curlus b. Organism has three feet – Narrowus squintflippus

17 – a. Organism has spots – Narrowus dispottis b. Organism has no spots – Narrowus fuzzflippus

18 – a. Organism has a curly antennae – Roundus bareus b. Organism has a straight antennae – Roundus puffus

19 – a. Organism has two feet – go to 10 b. Organism has three feet – Roundus headfuzzus

Narrowus trispottis

Narrowus longspottis

Roundus tricurlus

Narrowus dispottis

 

 

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29.

30.

31.

32.

What is one difference between photosynthesis and respiration?

A cat is in the same order as a dog, the same class as a monkey, and the same family as a tiger. Which animal is the cat least related to?

An eagle and a grizzly bear both hunt for salmon. What type of relationship does the eagle have with the salmon?

Cells need nutrients to perform their many functions. Which two organ systems interact to deliver nutrients to the cell?

Respiration is done by plants.

Photosynthesis creates useful energy.

Photosynthesis uses glucose as a reactant.

Respiration uses glucose as a reactant.

cat

dog

tiger

monkey

competition

commensalism

mutualism

predation

muscular and digestive

endocrine and digestive

circulatory and digestive

reproductive and digestive

 

 

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33.

34.

35.

Why is crossing over in meiosis important?

A cheetah is adapted for running at high speeds. This helps the cheetah be able to catch a gazelle. Lions also eat gazelles. What type of relationship does the cheetah have with a lion?

An influenza virus attacks a human. Which two organ systems fight the virus?

It aids in cytokinesis.

It decreases the probability for mutations.

It makes four unique daughter cells.

It increases genetic diversity.

predation

competition

mutualism

commensalism

nervous and cardiovascular

endocrine and immune

circulatory and immune

digestion and endocrine

 

 

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36.

37.

Which level of this trophic pyramid represents 10% of the energy?

Which two body systems would defend a person from a fire?

primary consumers

tertiary consumers

producers

secondary consumers

immune and integumentary

nervous and cardiovascular

integumentary and nervous

muscular and endocrine

 

 

4/28/2020 Diamond Biology B – Spring — Orange — Quintero, Crystal – Activities

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38.

39.

Which organisms are missing from this food web?

Which type of tissue forms the woody portion of a sycamore tree?

producers and decomposers

tertiary consumers and producers

producers

microorganisms

primary xylem

secondary phloem

primary phloem

secondary xylem

 

 

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40. Photosynthesis occurs in the ___ organelle in phytoplankton.

ER

mitochondria

chloroplast

nucleolus

 
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Experiment exercises will deal with Diffusion and Osmosis

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This unit’s Experiment exercises will deal with Diffusion and Osmosis. Read through the introductory material located below and complete the questions found in the Unit 3 Experiment Answer Sheet.

How to Proceed

  • Read through the Experiment Exercise Introductions below.
  • Open the Unit 3 Experiment Answer Sheet and complete the following Experiment exercises this unit:
    • Experiment 3 Exercise 1 – Diffusion (~1 hr)
    • Experiment 3 Exercise 2 – Osmosis (~1.5 hrs)
  • Save your completed Unit 3 Experiment Answer Sheet and submit it no later than Sunday midnight (CT).

Diffusion – Introduction

This unit we are learning about the structure and function of cells. The plasma membrane, for example, is an important structure of all cells and it is responsible for regulating the passage of materials into and out of the cell. Plasma membranes are differentially (selectively) permeable, meaning some substances are allowed to enter and exit the cell, while the movement of other materials is either carefully regulated or blocked. Two ways in which materials can move freely across the cell membrane are diffusion and osmosis.

Diffusion is the movement of solutes (material dissolved in liquid) from an area of high concentration to an area of low concentration. If these areas are separated by a membrane, that membrane may or may not be permeable to the solute. The membrane is always permeable to water though and the movement of water across a membrane is a special form of diffusion called osmosis.

In our first exercise, we will examine diffusion of solutes through a semipermeable membrane and the factors that affect their movement. You’ll want to be sure to review our online lecture this unit on Cell Structure and pp 83 – 86 in your book. View the following two animations BEFORE starting this exercise:

McGraw-Hill. 2006. How Diffusion Works
http://highered.mheducation.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html (Links to an external site.)

McGraw-Hill. 2006. How Osmosis Works
http://highered.mheducation.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html (Links to an external site.)

When you are ready to begin, open the Unit 3 Experiment Answer Sheet and answer the questions associated with the first exercise.

Osmosis – Introduction

In our second exercise this unit, we will to take a closer look at osmosis; the movement of water across a membrane. The direction water moves depends on the relative concentration of solute molecules on either side of the membrane (in this case, these solutes are not able to cross the membrane). Furthermore, the presence or absence of cell walls (e.g., in plant cells) influences how cells respond to osmotic fluctuations in their environment. This exercise will examine the forces that determine whether water moves into or out of a cell.

We will be using the following website in this exercise. Be sure you are able to access and use this website before starting.

The Biology Place. No Date. Osmosis: Movement of Water across Membranes
http://www.phschool.com/science/biology_place/biocoach/biomembrane1/osmosis.html  (Links to an external site.)

Open the Unit 3 Experiment Answer Sheet and complete the questions for this exercise.

WEEK 3 EXPERIMENT ANSWER SHEET Please submit to the Week 3 Experiment dropbox no later than Sunday midnight.

SUMMARY OF ACTIVITIES FOR WEEK 1 EXPERIMENT ASSIGNMENT

· Experiment 3 Exercise 1 – Diffusion: Movement of Solutes across a Membrane

· Experiment 3 Exercise 2 – Osmosis: Movement of Water across a Membrane

Experiment 3 Exercise 1: Diffusion – Movement of Solutes across a Membrane

We will be using dialysis tubing to simulate a semipermeable membrane. This tubing allows small molecules (e.g., water, ions, glucose) to pass while preventing large molecules (e.g., macromolecules like proteins, starch, glycogen) from moving across. Be sure you have read over the suggested material before starting this exercise and that you have reviewed the following animations:

McGraw-Hill. 2006. How Diffusion Works https://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html

McGraw-Hill. 2006. How Osmosis Works https://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html

Experimental Design

A. The dialysis bag we will use is permeable to water and small molecules (e.g., less than 500 g/mol) and impermeable to large molecules (e.g., more than 500 g/mol).

B. The dialysis bag is filled with a mixture of glucose (molecular weight = 180 g/mol) and protein (molecular weight = 10,000 g/mol) dissolved in water. A small subsample of the dialysis bag contents is saved and will be used in Step 4.

C. The dialysis bag is then placed into a beaker of water. A small subsample of beaker water is also saved and is to be used in Step 4 as well.

image1.png

The presence or absence of glucose and protein will be determined using indicators. Indicators change colors in the presence certain materials. The two tests that we’ll use are the Benedict’s test for simple sugars (e.g., glucose) and the Biuret test for the presence of proteins.

· If glucose is present, the Benedict’s indicator will turn green. If no glucose is present, the solution will be blue.

· If protein is present, the Biuret indicator will turn violet. If the solution remains clear, then no protein is present.

D. The subsample of dialysis bag solution and the beaker water are tested for the presence of glucose and protein. See Table 1 below for the results.

E. The dialysis bag is then left in the beaker of water for 60 minutes.

F. At the end of 60 minutes, the dialysis bag solution and the beaker water are again tested for the presence of glucose and protein. See Table 1 below for the results.

Table 1. Results of testing of the dialysis bag and beaker contents at the beginning and end of the Experiment.

  Test for Glucose Test for Protein
  Beginning End Beginning End
Dialysis Bag Green Green Violet Violet
Beaker Blue Green Clear Clear

Questions

1. Summarize the results regarding the presence (+) or absence (-) of glucose and protein in the dialysis bag and beaker in Table 2 below (4 pts):

Table 2.

  Glucose Protein
  Beginning End Beginning End
Dialysis Bag        
Beaker        

2. Explain the movement or lack of movement of protein and glucose across the dialysis bag membrane (4 pts)

3. Which solution, that in the bag or that in the beaker, is hypotonic compared with the protein solution (2 pts)?

4. What factors affect the movement of molecules across a semipermeable membrane? Which factor plays the greatest role in biological systems (4 pts)?

5. Briefly explain what active transport is and how it differs from passive transport, especially in terms of concentration gradients (4 pts).

 

Experiment 3 Exercise 2: Osmosis – The Movement of Water across a Membrane

Before starting, let’s see what you know about the terms hypotonic, isotonic and hypertonic. Examine the diagrams below. Note that the small green circles represent dissolved solutes like salt, glucose, and amino acids. You can assume that the additional space surrounding the solutes is water and that the tan area is INSIDE the cell.

image2.png

Question

1. Define each term below in terms of solute concentration outside compared to the inside of the cell. You do not need to explain which direction water will move (3 pts).

a. Hypotonic –

b. Isotonic –

c. Hypertonic –

Procedure

A. Open the following website to get started:

The Biology Place. No Date. Osmosis: Movement of Water across Membranes http://www.phschool.com/science/biology_place/biocoach/biomembrane1/osmosis.html

B. Read over the information presented and then Click on image3.png

C. Then, Click on image4.png. Read through the information presented and be sure to click on Animate beneath the illustration.

Questions

2. What concentration of salt is isotonic to animal cells (1 pts)?

3. When cells are in isotonic solution, is there movement of water into or out of the cell? If so, describe this movement (3 pts).

 

Procedure (continued)

D. Click on image5.png.

E. Read through the information presented and be sure to click on Animate beneath the illustration. When ready, answer the following question.

Question

4. Describe the net movement of water molecules when cells are placed in a hypotonic solution. Explain why water moves this way (3 pts).

 

Procedure (continued)

F. Click on image6.png

G. Read through the information presented and be sure to click on Animate beneath each of the illustrations. Answer the following questions. Your answers should incorporate the terminology used in the animations.

Questions

5. What happens to an animal cell when placed in a hypotonic solution (2 pts)?

6. What happens to plant cells when placed in a hypotonic solution? What accounts for the difference in outcomes between animal cells and plant cells (3 pts)?

 

Procedure (continued)

H. Click on image7.png

I. Then, Click on image8.png. Read through the information presented and be sure to click on Animate beneath the illustration. Answer the following question.

Question

7. Describe the net movement of water molecules when cells are placed in a hypertonic solution. Explain why water moves this way (3 pts).

 

Procedure (continued)

J. Click on image9.png

K. Read through the information presented and be sure to click on Animate beneath the illustration. Answer the following questions.

Questions

8. Compare and contrast what happens to plant and animal cells when placed in a hypertonic solution. Be sure to use proper terminology (4 pts).

9. Based on what you learned in this exercise, explain why salt might make a good weed killer (3 pts).

 

Week 3 Experiment Grading Rubric

Component Expectation Points
Experiment 3 Exercise 1 Interpretation of results and demonstrated understanding of diffusion (Table 2 and Questions 1-5). 18 pts
Experiment 3 Exercise 2 Demonstrates understanding of isotonic solutions and no net movement of water (Questions 1-3). 7 pts
  Demonstrates understanding of hypotonic solutions and the movement of water (Questions 4-6). 8 pts
  Demonstrates understanding of hypertonic solutions and the movement of water (Questions 7-9). 10 pts
TOTAL  
 
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