vce biology unit

Task 3: VCE Unit of work - Unit 4 Biology

Unit 4 - Continuity and ChangeThis unit focuses on genetics and investigates how features are passed from one generation to the next. The basis to genetics is a thorough understanding of the structure and workings of the molecule known as DNA. With features being passed on from one generation to the next, the theory that life can change over time is studied - the theory of evolution of species.DNA and inheritanceWhat exactly is DNA? What is the primary role of DNA? Where in the cells is DNA found and where in the cells is DNA active? What chemicals are made following the DNA 'code'? What is RNA and what does this molecule do? How are genes passed from parents to their offspring? Can you predict what sorts of genes will be found in offspring? Are genes inherited in families following any patterns? What modern technologies make use of the knowledge of DNA? What is cloning? What is genetically modified food? How does 'paternity testing' work?Changes over timeWhat is the modern theory of evolution? What forms of evidence exist to support the theory that species can change over time? How do we believe it possible for species to be able to evolve? What is the mechanism for evolving? What are fossils? How do we know how old fossils are? Which species are closely related to each other and which are not? How are such relationships worked out? What has been the history of human evolution? Where did humans come from? Are human actions having an effect on evolution? Should we play "God" and speed up the rate of evolution just to suit our own needs?

Area of Study 1 - DNA and Inheritance

Week Key Knowledge Assessment Tasks

1 GENES ARE RESPONSIBLE FOR TRAITS & CHARACTERISTICS Chromosomes: The gene carriers, the effects of having wrong

number of chromosomes Genes: The carriers of inherited instructions Alleles: Particular forms of a gene Identifying genotypes: Relationship between expression of alleles

2 GENES ARE RESPONSIBLE FOR TRAITS & CHARACTERISTICS Environment interactions with genotypes

o The effects of the environment on the expression of traits and characteristics – phenotypes

o How genes contribute towards the expression of traits and characteristics

Linked genes Family pedigrees

o Understanding how genetic materials can be passed down from our ancestors

3 CELLS REPRODUCE IN A PROCESS KNOWN AS THE CELL CYCLE Purpose of cell reproduction; Cell cycle and apoptosis Phases of Mitosis and Cytokinesis Meiosis: inputs and outputs; how it results in genetic

recombination When Meiosis goes wrong:

o Down Syndrome; Polyploidy

Outcome 1SAC 1

4 THE POLYMERS RESPONSIBLE FOR THE PASSING ON OF GENETIC INFORMATION FROM PARENTS TO OFFSPRING CONSISTS OF FOUR NUCLEOTIDES

The Nature and Structure of DNA DNA vs RNA: what, where, why Gene Expression Part I: Transcription Synthesising messenger RNA

5 THE POLYMERS RESPONSIBLE FOR THE PASSING ON OF GENETIC INFORMATION FROM PARENTS TO OFFSPRING CONSISTS OF FOUR NUCLEOTIDES Gene Expression Part II: Translation

o Codons + Anticodonso Transfer RNA Amino Acid attachment o Anticodons

Gene expression is regulated MUTATION LEADS TO VARIATION What are mutations; Point mutations (substitution and frame

shift); effects on amino acid sequence

6 MUTATION LEADS TO VARIATION What are mutations; Point mutations (substitution and frame

shift); effects on amino acid sequence Germ line and somatic mutations Detecting mutations; how do mutations arise inc. mutagens Examples of mutations; case studies of genetic conditions caused

by mutationsGENES CAN BE MANIPULATED & CREATED WITH TECHNOLOGY DNA manipulation techniques: DNA Sequencing (Sanger and high

throughput), DNA Amplification (PCR), Gel Electrophoresis

7 GENES CAN BE MANIPULATED & CREATED WITH TECHNOLOGY DNA manipulation techniques: DNA Sequencing (Sanger and high

throughput), DNA Amplification (PCR), Gel Electrophoresis Restriction digestion, DNA recombination gene cloning, gene

transformation, gene delivery Forensics: DNA Profiling - micro-sattelites, RFLP, DNA sequence Measuring genes: gene Expression, Microarrays, high throughput

sequencing Genetic Engineering: Transgenic crops Ethics

Outcome 1SAC 2

Area of Study 2 – Changes of Time

Week Key Knowledge Assessment Tasks

1 Change in populations: gene pool, allele frequencies; selection pressures; genetic drift

2 Natural selection as a mechanism of evolution Geological time: scale; relative and actual dating techniques.

3 Investigate evidence of evolution: including the fossil record, biogeography, comparative anatomy and molecular evidence.The development of evolutionary theory.

Outcome 2: Assessment Task 1

4 Patterns of evolution: divergent, convergent; allopatric speciation, extinction.Evolutionary relationships: conservation of genes; genome phylogeny; mitochondrial evolution.

5 Hominid evolution: patterns, origin. interrelationships between biological, cultural and technological evolution

6 Students will understand human intervention in evolutionary processes, including selective breeding, and the application of gene technologies (cloning of organisms; transformation; stem cell differentiation; genetic screening, gene therapy)

Outcome 2: Assessment Task 2

LESSON PLAN 1

TopicMutations

Unit 4 Week 5

AimsStudents will be able to demonstrate how mutations change the amino acid sequence

Students will be able to explain the different between mutations

Standards

Students know that mutations in the DNA sequence of a gene may or may not affect the expression of the gene or the sequence of amino acids in an encoded protein.

Location / Setting

SCI Room

Organisation / Student GroupsIn their chairs or in groups around the experiment tables

Classroom management strategy

Rules:1. Listen and follow directions.2. Raise your hand before speaking or leaving your seat.3. Keep your hands and feet to yourself.4. Respect your classmates and your teacher.Consequences:1st time a rule is broken: Warning2nd time a rule is broken: Moved within class (teacher discretion)3rd time a rule is broken: 5 minute removal outside of classroom (student must be located immediately outside of classroom)4th time a rule is broken: Resolution meeting (classroom teacher/student meeting is organised)

Key VocabularyMutation, DNA, RNA, sequence, codon, gene, base pairing,

Materials, Resources and Equipment

Projector, lap top, computer, pens/paper, handout

References/Sources

Textbook: Nelson Biology VCE Units 3 and 4

Powerpoint explaining mutation and gives examples of mutations e.g. cancer, sickle cell anaemia

INTRODUCTIONConnecting, Engaging and Modelling Inquiry

MAIN BODY

Guiding Inquiry and Practise

CONCLUSIONSharing, Explaining and Reviewing Inquiry

This lesson is designed to help Therefore a 'mutation is a Hand out 'Gene Mutations Sheet',

students explore different types of genetic mutations and

how they can affect an organism from the molecular level to the systemic level and even extending into the population.

Briefly reiterate base pairing rule of DNA (A-T and C-G), and codon's are '3' DNA sequence which corresponds to a specific amino acid or 'stopper'. However mutations can occur through one of two processes:

1. DNA damage from environmental agents such as UV light (sunshine), nuclear radiation or certain chemicals

2. Mistakes that occur when a cell copies its DNA in preparation for cell division (therefore during replication, which can happen about once every 100,000,000 bases)

Mutations are when base pairs stray from the pairing rule (C-G and A-T only) which can cause a different amino acid to be called and this causes mutations.

permanent change in the DNA sequence of a gene. Mutations in a gene's DNA sequence can alter the amino acid sequence of the protein encoded by the gene.'

Write on the board:We can think about the DNA sequence of a gene as a sentence made up entirely of three-letter words. Each three-letter word is a codon, specifying a single amino acid in a protein. How would this sentence look if it was a codon:

Thesunwashotbuttheoldmandidnotgethishat

(The sun was hot but the old man did not get his hat) This sentence represents a gene, each letter corresponds to a nucleotide base and each word represents a codon.

read and work through this sheet. Any questions raise your hands.

Worksheet is due at the end of class, please hand them in with your names on the front and they will be marked accordingly.

Research "What type of a mutation (point or frameshift) causes sickle cell anaemia? How do you know?"

Name: Date:

Gene Mutations Worksheet

There are two types of mutations, small-scale gene mutations and large-scale chromosomal mutations. You will do gene (point) mutations in this handout. Since mRNA is read in threes (codons), an addition or deletion of a base changes the reading frame of the sequence.

Frame shift Mutations

DNA Sequence: THE BOY CUT HIS LIP AND ATE THE HOT DOG

Insertion Example: THE BOY CUT HIS SLI PAN DAT ETH EHO TDO

Insert a base

Delete a base

DNA Sequence: THE BOY CUT HIS LIP AND ATE THE HOT DOG

Deletion Example: THE BOY CUT HIS LIP ANA TET HEW OTD OG

The insertion shifts the reading frame to the right, while the deletion shifts the reading frame to the left. Insert a letter C for the two insertion questions. For the deletion questions, delete the H or one base letter.

Write each codon per line

DNA Sentence THE BOY CUT HIS LIP AND ATE THE HOT DOG

Insertion THE BOY ___ ___ ___ ___ ___ ___ ___ ___

Deletion THE BOY CUT ___ ___ ___ ___ ___ ___ ___

Now use real DNA code and translate it into the correct amino acids. Decide where in the original DNA code to case a mutation on the rest of the questions. Please use the codon table on the last page to find the corresponding amino acids.

Write each codon per line and circle the mutated DN base where the mutation took place.

Original DNA TAC GGA CGA TCT CAG GAG CCT ATA ATC

Insertion DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated Amino Acids ___ ___ ___ ___ ___ ___ ___ ___ ___

Original Amino Acid Met Pro Ala Arg Val Leu Gly Tyr STOP

Write each codon per line and circle the mutated DNA base where the mutation took place

Original DNA TAC GGA CGA TCT CAG GAG CCT ATA ATC

Deletion DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated Amino Acids ___ ___ ___ ___ ___ ___ ___ ___ ___

Original Amino Acid Met Pro Ala Arg Val Leu Gly Tyr STOP

Usually a frame shift mutation results in the synthesis of a non-functional protein. Why do you think your mutated proteins might not be functional?

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Base substitution mutations

For simplicity, change only one base for all the following substitution mutations

base substitution is a different type of gene mutation. It is the simplest type of mutation where a nucleotide pair is replaced with a different nucleotide pair.

Base substitution GAC GGC

One type of base substitution is called transversion mutation. Transversion mutation happens when one purine (A, G) is swapped with a pyrimidine (C, T).

Purine Pyrimidine GAC TAC

Pyrimidine Purine GAC GAG

Use the DNA code below to demonstrate a purine pyrimidine transversion mutation. All you have to do is change one DNA base.

Write each codon per line and circle the mutated DNA amino acid

Original DNA TAC CAT GCA GAT CTG GCC CAG TTC ATC

Transversion DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated Amino Acid ___ ___ ___ ___ ___ ___ ___ ___ ___

Original Amino Acid Met Val Arg Leu Asp Arg Val Lys STOP

The opposite of transversion mutations are transition mutations. A transition mutation happens when one purine is swapped with the other purine or a pyrimidine with pyrimidine.

Purine Purine GAC AAC

Pyrimidine Pyrimidine GAC GAT

use the DNA code below to demonstrate a purine purine transition mutation. All you need to do is change one DNA base.

Write each codon per line and circle the mutated DNA amino acid

Original DNA TAC GTC GCT CAA CGG GAC CTG ACC ACT

Transition DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___


Original Amino Acid Met Gln Arg Val Ala Leu Asp Trp STOP

A third type of base substitution is called silent mutation. Silent mutation happens when one base in a codon is changed, but both code for the same amino acid

DNA CTT CTG

Amino Acid Leu Leu

Use the DNA code below to demonstrate a silent mutation. All you need to do is change one DNA base but the amino acid stays the same.

Write each codon per line and circle the mutated DNA base

Original DNA TAC CAT TCT CGG TGT AAA GCG ATT

Silent DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Original Amino Acid Met Val Arg Ala Thr Phe Ser Arg STOP

A base mutation that creates a new stop codon in place of an amino acid is called a nonsense mutation

DNA TGT TGA

Amino Acid Cys STOP

Write each codon per line and circle the mutated amino acid

Original DNA TAC GGT CAA ATA GAA CCT GAG ACT

Nonsense DNA ___ ___ ___ ___ ___ ___ ___ ___ ___

Mutated mRNA ___ ___ ___ ___ ___ ___ ___ ___ ___


Original Amino Acid Met Pro Leu Val Tyr Leu Gly Leu STOP

Please explain the difference between a frame shift mutation and a base substitution mutation

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LESSON PLAN 1TopicNatural Selection

AimsStudents will be able to demonstrate and explain how natural selection is a mechanism for evolution.

Standards

Natural selection is key to evolution

Location / Setting

SCI Room



Rules:1. Listen and follow directions.2. Raise your hand before speaking or leaving your seat.3. Keep your hands and feet to

yourself.4. Respect your classmates and your teacher.Consequences:1st time a rule is broken: Warning2nd time a rule is broken: Moved within class (teacher discretion)3rd time a rule is broken: 5 minute removal outside of classroom (student must be located immediately outside of classroom)4th time a rule is broken: Resolution meeting (classroom teacher/student meeting is organised)

Key VocabularyNatural selection, evolution, variability, heritability, differential reproduction, environment, predator, prey, traits, genes,



References/Sources


Powerpoint explaining natural selection and its evidence throughout time


MAIN BODY


CONCLUSIONSharing, Explaining and Reviewing

Inquiry

Understanding evolution is the key to understanding diversity. Natural selection, being the mechanism (or cause) of evolution must also be well understood. Students may understand evolutionary change and how it works in a general sense, they need to broaden their thinking from the specifics of individuals with certain traits to how the traits in a whole population can change.

Hand out natural selection game sheet 'Simulating Natural Selection'

Work through sheet and play the game of natural selection in a group no more than 4 students.

Each student needs a grid 5x5, pens and paper and follow the instructions on the hand out

Questions:

1. Did the average camouflage and visual acuity increase or decrease? By how much?2. Compare the initial and final frequency distributions in Figure 3. Did the variability of the two populations change? By how much? (Hint: an approximate measure of variability is the range of scores for each population.)3. Give two examples of chance events that might affect the course of evolution in nature.4. If the initial size of each population was much larger (e.g. 1000 instead of 16) would the effect of chance events on evolution be more or less important? Explain.5. Sometimes in these simulations a population will go extinct. Is extinction more likely for a small or large population? Why?6. Did the size of the prey and predator populations change during the simulation? How and why?

MULATING NATURAL SELECTION

You will recall that several conditions are necessary for natural selection to occur:

1. VARIABILITY. Individuals within a population must be different from each other. These differences may involve characteristics such as resistance to cold, susceptibility to disease, photosynthetic efficiency or the ability to attract a mate, to name just a few.

2. HERITABILITY. Some of the variability between individuals must have a genetic basis. Thus offspring will tend to resemble their parents and have the same traits.

3. DIFFERENTIAL REPRODUCTION. Individuals with some traits will leave more descendants than others. This could be either because they survive longer (e.g. faster animals are better at escaping from predators) or because they have a higher reproductive rate (e.g. a bird with more colorful plumage may attract more mates.)

Playing the Game

The game is played on a board divided into 5 rows and 5 columns. Each animal is represented by a piece of paper with a number written on it to indicate the animal's camouflage or visual acuity. Different color paper will be used for predators and prey. Each round begins by randomly placing the predators and prey on the board. Predators then search for prey within their square and, if successful, reproduce. Predators that do not catch any prey within two rounds starve. At the end of each round those prey that have managed to survive can reproduce, but only if they are not too crowded.

Each student at a table has a different task. If there are fewer than four students some of these tasks can be combined.

a. The GAME MASTER has the primary responsibility for carefully reading the instructions and ensuring that each step is performed properly, and in the correct sequence. In case of questions ask your instructor before continuing. If the instructions are not followed to the letter the simulation will fail and you will have to start over.

b. The RANDOMIZER reads numbers off a random numbers table. These numbers are used when placing animals on the board randomly at the beginning of each round. The use of a random numbers table is analogous to rolling dice. It adds an element of chance to the simulation.

c. The DISTRIBUTOR is in charge of placing and removing pieces from the board. The random numbers read by the second person determine where a particular piece is placed.

d. The RECORDER cuts up and labels additional pieces as they are needed. This person should also record and graph the results as they come in.

Figure 1. Two game pieces, a prey with a camouflage score of 5 and a predator with a visual acuity score of 8. The predator was born in round 0. If it does not feed in round 1 or 2 it will starve.

Table 1. Initial Frequency Distribution of Traits in Predator and Prey Populations. This shows the number of prey and predators with a particular camouflage score or visual acuity, respectively. See Figure 3.

Camouflage / Vision Score # Prey Pieces # Predator Pieces

Worst 2 1 1

3 2 2

4 3 3

5 4 4

6 3 3

7 2 2

Best 8 1 1

Total # Pieces: 16 16

What is the average camouflage score of the prey population ? ________

What is the average visual acuity of the predator population? ________

Keep in mind that these numbers are starting values. After a couple of rounds the scores may be much higher. Scores can go above 8 but they cannot go below 0.

ROUND 1:

Here is where the animals are actually placed on the board and begin to interact with each other. Take your time with this round as you learn the rules of play. Subsequent rounds will go faster. Be sure to ask your instructor if any of the instructions are not clear.

a. DISPERSAL. Use the table of random numbers to put each animal in turn on the board. You can begin anywhere on the table and read numbers from top-to-bottom or left-to-right. Each pair of numbers represents the coordinates of one of the squares on the board. For example, if the number is 25 place the animal in column 2 - row 5.

b. PREDATION. After all animals are placed on the board each predator now has a chance to eat and reproduce, but only if there is a prey in the same square with a camouflage score less than the predator's visual acuity. For example, a predator with a visual acuity of 6 will detect and eat a prey with a camouflage score of 5, but not one with a score of 7. If the predator and prey have the same number flip a coin to see who wins. Remove dead prey immediately. After a predator eats it then reproduces as described in (c) below.

If there are more than one predator and/or prey on a square these rules apply:

- If there are two predators the one with the greatest visual acuity will see the prey first and eat it.

- If there are two prey, the one with the poorest camouflage will be seen and eaten first.

- A predator can eat only one prey. It then reproduces and dies (see below).

c. PREDATOR REPRODUCTION. When a predator eats it obtains enough energy to produce two offspring. Then it dies and is removed from the board. Remember that in nature parents and their offspring tend to resemble each other but are not identical. To simulate this let one of the two offspring have a visual acuity score greater than the parent by 1 (there in no upper limit to visual acuity). Give the second offspring a score that is one less than the parent, but no lower than 0. If there are any uneaten prey still in the square the offspring can immediately eat them (and reproduce themselves) if their visual acuity is high enough. Thus, you could have several generations of predators in one round.

Mark each new offspring with the round in which it was born (in this case round 1). Figure 2 illustrates an example of an interaction (steps b and c) within one square on the board.

Figure 2. A predator with a visual acuity of 8 eats a prey with a camouflage of 5 and then reproduces and dies.

d. STARVATION. Normally in step (d) predators that had not eaten in two rounds would starve. In Round 1, however, none of the predators have been around long enough so skip this step for now.

e. PREY REPRODUCTION. All surviving prey now have the opportunity to reproduce. However, a prey can reproduce only if no other prey occupy the same square. If two prey occupy the same square there is not enough food to supply the energy needed for reproduction. However, prey do not starve. They survive into the next round. (The presence of predators in the square does not prevent a prey animal from reproducing since predators do not compete for the same food eaten by the prey.) Reproduction by prey is the same as in predators. Each prey is replaced by two offspring, one of which has better camouflage (by 1) and one of which has worse camouflage (by 1), except that camouflage can never drop below 0.

f. RECORD RESULTS. At the end of each round calculate the average scores for surviving predators and prey. Record these numbers in Table 2 NOW!

ROUND 2:

Round 2 is similar to Round 1 except now any predators that have not eaten in two rounds will starve.

a. Did you record the average scores of predators and prey after the previous Round? If so, then remove all the animals from the board and, using the random numbers table, redistribute them as you did before.

b. Predators eat and reproduce if their square is occupied by a prey with a lower score. Label new predators with the round in which they were born (2).

c. Predators that have not eaten in two rounds starve and are removed. Since this is Round 2 any predators labelled with a 0 starve. Remove them from the board.

d. Prey reproduce as before.

e. Record the number of predators and prey in Table 2.

ROUNDS 3, 4, 5, . . . .

Repeat the steps of the previous round for as long as time permits, or until one of the populations goes extinct. Remember to remove any predators that have not eaten in two rounds and to mark all new predators with the round in which they were born.

Data Analysis

1. Figure 3 shows the initial frequency distribution for each population. Draw your final frequency distribution on the same graph.

2. On Figure 4 plot the average score of each population over time and on Figure 5 plot the size of each population over time.

Table 2: Record the average score and number alive at the end of each round. You may complete more or less than 10 rounds depending on time.

PREY POPULATION PREDATOR POPULATION

ROUND Avg. Score # Alive Avg. Score # Alive

0 5.0 16 5.0 16

1

2

3

4

5

6

7

8

9

10

Table 3: After the last round record the number of pieces with a particular score for both predators and prey. Plot these numbers on the frequency distribution in Figure 3.

SCORE # Prey # Predators

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

Plot the average score (top graph) and population size (bottom) over time. Use triangles for predators, squares for prey and then draw a line to connect them. The initial values for Round 0 are already plotted.

Class Discussion

have each group plot the average scores on the board. This results in two graphs, one for the predators and one for the prey, with one line for each group.

Possible discussion questions include:

1. What is the mode of selection?

Directional

2. Why aren't the curves smooth?

There are actually two processes going on simultaneously. Directional Natural Selection and Genetic Drift. The latter refers to chance events that result in random fluctuations in allele frequencies within a population

LESSON PLAN 3TopicInfectious disease and population growth

AimsStudents will be able to gain understanding of crosscutting concepts (stability & change; patterns) and on disciplinary core idea (ecosystem dynamics, functioning and resilience)

Standards

Disease invasion and how we can cope

Location / Setting

SCI Room



Rules:1. Listen and follow directions.2. Raise your hand before speaking or leaving your seat.

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3. Keep your hands and feet to yourself.4. Respect your classmates and your teacher.Consequences:1st time a rule is broken: Warning2nd time a rule is broken: Moved within class (teacher discretion)3rd time a rule is broken: 5 minute removal outside of classroom (student must be located immediately outside of classroom)4th time a rule is broken: Resolution meeting (classroom teacher/student meeting is organised)

Key VocabularyDisease, population, environment, ecosystem. resilience, infection, interaction, exponential growth



References/Sources


Powerpoint explaining disease and infectious diseases - causes, symptoms and cures (if any)


MAIN BODY


CONCLUSIONSharing, Explaining and Reviewing Inquiry

- Spread of infectious disease from person to person in a population can result in exponential increase in the number of infected people.

- Similarly, when population size doubles repeatedly, this results in exponential growth.

- Population growth is limited by the availability of resources.

- The maximum population size that an environment can sustain is called the carrying capacity.

- As population size approaches the carrying capacity, the rate of growth in population size decreases, resulting in a logistic growth curve.

T h e Sp r e ad of an I n f ec t io u s Di s e a s e

Equipment and Supplies:

Prepare a basic solution as the infected solution. Make sure the solution is concentrated enough that your indicator will change colour when added to solution that has been diluted to 1/8 strength.

Prepare two sets of cups (each with one cup per student) for the two sets of interactions (instructions 1-3 and 4 on page 1 of the Student Handout). For each set, fill one of the cups one quarter full with the infected solution. Fill all the other cups one quarter full with plain water.

Explain that each student will receive a cup containing a clear solution. Tell the students that the solutions represent bodily fluids.

3. The simulation showed the way a disease could spread if the spread of disease depends on person-to-person contact. Examples of this kind of disease include pink eye, chickenpox and herpes (lip sores). Other diseases, such as colds and tuberculosis, can be spread by germs in the air. How might the spread of these diseases differ from the spread of diseases that

depend on person-to-person contact?

4. In addition to exposure to germs (bacteria or viruses), what other factors influence your risk of getting an infectious disease? What defences does your body have that can prevent you from getting sick, even when you have been exposed to germs?

5. Once you have caught a cold or flu, you do not stay sick forever. How does your body eventually get rid of the viruses that cause a cold or flu?

Small Dixie cups (3-5 oz; 2 cups per student)

Chemical (such as Calgon water softener or NaOH) to mix with water to produce a clear solution

with a basic pH of 10 or above

Phenolphthalein pH indicator*

(You can substitute any basic indicator that is clear until in a basic solution.) Small container with eye dropper or pipette for phenolphthalein

Container for mixing basic solution

Answer discussion questions on sheet 6-16 and hand sheets to teacher

Additional question to aid class discussion:

1. What are some ways that infectious diseases are transmitted from one person to another?

2. are some ways you can prevent the spread of an infectious disease?

6. In almost every case, a person who becomes infected with the HIV virus is infected for the rest of his or her life. With highly effective modern medical treatment, a person may survive a long time with an HIV infection. However, an untreated HIV-infected individual is very likely to eventually develop AIDS and die. Why is a person with an HIV infection unable to get rid of this infection the way a person can get rid of an infection with a cold or flu virus?

Some Similarities between the Spread of an Infectious Disease and Population Growth

An infectious disease is any disease caused by germs that can be spread from one person to another. Germs include viruses, bacteria and protozoa. What are some infectious diseases?

This activity will simulate the spread of an infectious disease. A simulation is a simplified demonstration of a real biological process. Our simulation will show how an infectious disease can spread from one infected person to other people, who in turn infect others.

Instructions

1. Your teacher will give everyone a cup filled with a clear solution. This solution represents your body. Only one person in the class will have a cup that has been “infected”.

2. In this part of the activity, you will interact with two other students. To interact with another student, pour all of your solution into your partner’s cup. Then have your partner pour all of the mixed solution back into your empty cup. Finally, pour half of the mixed solution back into your partner’s empty cup.

Wait for the signal from your teacher, and then move to another part of the classroom and interact with a second student. After you have finished your second interaction, return to your seat.

Estimate how many people you think will be infected ________

3. Your teacher will come around and put an “infection indicator” in your cup. If you have exchanged solutions with the original infected person or someone else after they became infected, you are now infected and your solution will turn pink. If you have not exchanged solutions with anyone who was infected, your solution will not turn colour.

Next, your teacher will ask everyone who is infected to raise their hand.

How many people were infected ________

4. You will do another set of interactions, again beginning with only one student with an infected cup. This time there will be three rounds of interactions. For each interaction, be sure to move to a different part of the room with different students.

Estimate how many people you think will be infected after each student has interacted with three other students ________

After the teacher has come around with the indicator, write down how many people were actually infected ________

5. Now you will graph how an infection spreads to infect more and more people after each interaction.

First, plot a point to indicate that one person was infected before any interactions. How many people would be infected after just one interaction? _______

Add this point to your graph

Next, plot the number of people who were infected after two interactions (from 3 on page 1) and the number of people who were infected after three interactions (from 4 on page 1).

Discussion Questions

6. How many people developed a new infection as a result of the first round of interactions?

How many people developed a new infection as a result of the second round of interactions?

How many people developed a new infection as a result of the third round of interactions?

Which round of interactions resulted in the biggest increase in the number of infected people?

In each round of interactions, each infected person can infect one new person. Therefore an interaction that begins with more infected people will generally result in more new infections.

7. How many people do you think would be infected if your class had four interactions? Explain your reasoning.

Unit 4 - Changes over time - SAC 4

A response to an issue related to an application of gene technologies. This SAC is designed to allow students to;

Demonstrate knowledge of the different methods and reasons for human intervention in evolutionary processes

Demonstrate understanding of the interrelationships between biological, cultural and technological evolution Demonstrate understanding of the issues presented Analyse and evaluate the reliability of information and opinions expressed communicate using appropriate scientific terminology and conventions Have the opportunity to demonstrate the highest level of performance.

As in all School Assessed Tasks, the teacher will be grading the work according to stated VCAA criteria. In undertaking the task, there is scope for students to maximise their opportunity of receiving full marks. The following is a summary of assessment guidelines

Knowledge of the evolutionary process Evaluation of the impact on evolution by humans Evaluation of the reasons for human intervention in evolutionary processes Understanding of the interrelationships between biological, cultural and technological evolution Evaluation of the reliability of the information and opinions expressed Relevant application of appropriate scientific terminology and conventions

Ability to communicate information and understanding to the intended audience

Unit 4 SAC 4

Response to an issue related to an application of gene technologies

You have been asked to present to a year 12 biology student conference on the issues associated with human intervention in evolutionary processes through gene technologies.

Each group (2-3 people) will pick one of the following examples of human intervention in evolutionary processes:

cloning of organisms stem cells genetic screening & gene therapy transformation/genetic modification

You will need to:

Identify the intervention and how it is carried out (i.e. the technology used) Outline the reasons for the intervention. Discuss the issues arising from the intervention, both positive and negative Evaluate the arguments and opinions for and against the intervention Discuss how the intervention impacts on natural selection and long term evolution of the target

species.

You will be presenting your paper as an A3 poster and 10-15 minute talk discussion on it for the conference proceedings. (NB these posters will be scanned and provided to each member of the class as a revision tool, so please make sure they are clear and easy to understand.)

The assessment rubric for this task can be seen over the page. In order to complete this task, you will have the holidays and two lessons after the break. You also need to submit a bibliography (Harvard style) on the back of your poster.

Poster presentations will take place on Friday 12th October.

Unit 4 SAC 4Response to an issue related to an application of gene technologies

RubricsExcellent

(5 marks)

Very Good

(4 Marks)

Good

(3 Marks)

Satisfactory

(2 Marks)

Poor

(1 Mark)

Unsatisfactory

(0 Marks)

Understanding of reasons for human intervention in evolutionary processes and technology used

Critical evaluation of reasons for human intervention.

Detailed and relevant evaluation of reasons for human intervention.

Relevant evaluation of reasons for human intervention.

Some relevant evaluation of reasons for human intervention.

Limited evaluation of reasons for human intervention.

Not shown

Understanding of the issues arising from the intervention, both positive and negative

Comprehensive and detailed understanding of the evolutionary process.

Thorough knowledge of the evolutionary process.

General knowledge of the evolutionary process.

Some knowledge of the evolutionary process.

Limited knowledge of the evolutionary process.

Not shown

Evaluation of the arguments and opinions, both for and against

Critical evaluation of the reliability of the information and opinions expressed.

Thorough evaluation of the reliability of the information and opinions expressed.

Evaluation of the reliability of the information and opinions expressed.

Some evaluation of the reliability of the information and opinions expressed.

Limited evaluation of the reliability of the information and opinions expressed.

Not shown

Evaluation of the impact on evolution by humans

Critical evaluation of the impact on evolution by humans.

Thorough evaluation of the impact on evolution by humans.

Evaluation of the impact on evolution by humans.

Some evaluation of the impact on evolution by humans.

Limited evaluation of the impact on evolution by humans.

Not shown

Ability to communicate information and understanding to the intended audience using appropriate terminology and conventions.

Bibliography.

Comprehensive and relevant application of scientific terminology and conventions. Reflects a very high level of ability to communicate to intended audience.

Contains at least one book and 5 internet sources

Detailed and relevant application of scientific terminology and conventions. Reflects a high level of ability to communicate to intended audience.


Relevant application of scientific terminology and conventions. Reflects a good ability to communicate to intended audience.


Some application of scientific terminology and conventions. Shows some ability to communicate to intended audience.

Contains 4-5 internet sources

Limited application of scientific terminology and conventions. Limited ability to communicate to intended audience.


Not shown


Total and comments

vce biology unit

Documents

knowledge of dna

dna code

dna active

structure of dna dna

expression of traits

sorts of genes

nucleotides gene expression

expression of alleles