Living Environment: Genetics Unit Plan

Living Environment: Genetics Unit

Unit Overview:

Organisms from all kingdoms possess a set of instructions (genes) that determines their characteristics. These instructions are passed from parents to offspring during reproduction. Students are familiar with simple mechanisms related to the inheritance of some physical traits in offspring. They are now able to begin to understand the molecular basis of heredity and how this set of instructions can be changed through recombination, mutation, and genetic engineering.

The inherited instructions that are passed from parent to offspring exist in the form of a code. This code is contained in DNA molecules. The DNA molecules must be accurately replicated before being passed on. Once the coded information is passed on, it is used by a cell to make proteins. The proteins that are made become cell parts and carry out most functions of the cell.

Throughout recorded history, humans have used selective breeding and other biotechnological methods to produce products or organisms with desirable traits. Our current understanding of DNA extends this to the manipulation of genes leading to the development of new combinations of traits and new varieties of organisms.

Target Group/ Environment:

Middle school learners, classroom and lab setting

Materials/Equipment Needed:

Powerpoint projector

Basics of Genetics Worksheet

Pieces of paper for each student

Meiosis/mitosis worksheet

Chromosomes handout

Male/female karyotypes

Colored pencils

Cutouts of basic subunits of DNA

Scissors

Tape or glue

Envelopes

Construction paper

Computer Lab

Genetics review sheet

Test papers

Extra pencils

Sources/Purpose:

Students will learn how to:

Explain how the structure and replication of genetic material result in offspring that resemble their parents.

Explain how the technology of genetic engineering allows humans to alter genetic makeup of organisms.

Standards and Objectives:

2.1a Genes are inherited, but their expression can be modified by interactions with the

environment.

2.1b Every organism requires a set of coded instructions for specifying its traits. For offspring

to resemble their parents, there must be a reliable way to transfer information from one generation to the next. Heredity is the passage of these instructions from one generation to another.

2.1c Hereditary information is contained in genes, located in the chromosomes of each cell. An inherited trait of an individual can be determined by one or by many genes, and a single gene can influence more than one trait. A human cell contains many thousands of different genes in its nucleus.

2.1d In asexually reproducing organisms, all the genes come from a single parent. Asexually produced offspring are normally genetically identical to the parent.

2.1e In sexually reproducing organisms, the new individual receives half of the genetic information from its mother (via the egg) and half fromits father (via the sperm). Sexually produced offspringoften resemble, but are not identical to, either of their parents.

2.1f In all organisms, the coded instructions for specifying the characteristics of the organism are carried in DNA, a large molecule formed from subunits arranged in a sequence with bases of four kinds (represented by A, G, C, and T). The chemical and structural properties of DNA are the basis for how the genetic information that underlies heredity is both encoded in genes (as a string of molecular “bases”) and replicated by means of a template.

2.1g Cells store and use coded information. The genetic information stored in DNA is used to direct the synthesis of the thousands of proteins that each cell requires.

2.1h Genes are segments of DNA molecules. Any alteration of the DNA sequence is amutation. Usually, an altered gene will be passed on to every cell that develops from it.

2.1i The work of the cell is carried out by the many different types of molecules it assembles, mostly proteins. Protein molecules are long, usually folded chains made from 20 different kinds of amino acids in a specific sequence. This sequence influences the shape of the protein. The shape of the protein, in turn, determines its function.

2.1j Offspring resemble their parents because they inherit similar genes that code for the production of proteins that form similar structures and perform similar functions.

2.1k The many body cells in an individual can be very different from one another, even though they are all descended from a single cell and thus have essentially identical genetic instructions. This is because different parts of these instructions are used in different types of cells, and are influenced by the cell’s environment and past history

2.2a For thousands of years new varieties of cultivated plants and domestic animals have resulted from selective breeding for particular traits.

2.2b In recent years new varieties of farm plants and animals have been engineered by manipulating their genetic instructions to produce new characteristics.

2.2c Different enzymes can be used to cut, copy, and move segments of DNA. Characteristics produced by the segments of DNA may be expressed when these segments are inserted into new organisms, such as bacteria.

2.2d Inserting, deleting, or substituting DNA segments can alter genes. An altered gene may be passed on to every cell that develops from it.

2.2e Knowledge of genetics is making possible new fields of health care; for example, finding genes which may have mutations that can cause disease will aid in the development of preventive measures to fight disease. Substances, such as hormones and enzymes, from genetically engineered organisms may reduce the cost and side effects of replacing missing body chemicals.

Contents:

Lesson 1: Intro to Genetics

Basics of Genetics Worksheet

Lesson 2: The Role of Genes

Pieces of paper for each student

Lesson 3: Reproduction and Heredity

Meiosis/mitosis worksheet

Lesson 4: Chromosome Lab Activity

Chromosomes handout
Male/female karyotypes
Colored pencils

Lesson 5: DNA: The Blueprint for Life

Cutouts of basic subunits of DNA
Scissors
Tape or glue
Envelopes

Lesson 6: Function of DNA

Cutouts of bases from last class period
Scissors
Tape or glue

Construction paper

Lesson 7: Mutations

Organizer (for presentation/research outline)
Computer lab for 2nd half of class
List of genetic diseases

Lesson 8: Selection Lecture and Exam Review/ Research Period

Computer Lab
Genetics review sheet

Lesson 9: Genetics Unit Test

Test papers
Extra pencils for students

Appendix: Genetics Unit Slideshow, Meiosis/Mitosis Slideshow, Mutation Slideshow

Lesson Plan- Day 1: Intro to Genetics

Standards:

Key Idea 2: Organisms inherit genetic information in a variety of ways that result in continuity of structure and function between parents and offspring.

2.1a Genes are inherited, but their expression can be modified by interactions with the environment.

2.1b Every organism requires a set of coded instructions for specifying its traits. For offspring to resemble their parents, there must be a reliable way to transfer information from one generation to the next. Heredity is the passage of these instructions from one generation to another.

Objective:

Students will be able to define what a gene is and why heredity is responsible for the variation in species, including humans through the in-class completion of a worksheet on the basics of genetic principles and terms.

Materials: Powerpoint projector, Basics of Genetics Worksheet

Procedure:

10 minutes- Introduction on genetics, ask students what the term reminds them of, discuss examples of genetics at work: cloning, inheritance (hair/eye color, height, “weird” traits (ie. tongue rolling, color blindness)

10 minutes: Present content via powerpoint slides 1-5. Order of ideas: What is genetics? -> What is a gene?-> Genes determine traits (examples of traits, such as height, eye color, etc.) -> Genetics can allow us to study how traits are passed from generation to generation (heredity). Vocabulary words: gene, genetics, traits, heredity. Discuss definitions as well as examples (eg. There is a gene for hair color, etc.)

15 minutes: Hand out worksheets and have students work in partners to complete before end of class. Will be collected and graded as a homework assignment.

5 minutes: Exit slip: collect worksheets on the way out. Ask students: what are examples of heredity?

Assessment:

Exit slip question, work sheet completion

Lesson Plan- Day 2: The Role of Genes

Standards：

2.1h Genes are segments of DNA molecules. Any alteration of the DNA sequence is a mutation. Usually, an altered gene will be passed on to every cell that develops from it.

Objective:

Students will learn the idea that different traits are determined by different genes, there are thousands of different genes in humans, located on different parts of the chromosomes and that they are passed on from generation to generation. They will demonstrate their knowledge by completing one short answer question which they will turn in at the end of class.

Materials:

Powerpoint projector, Pieces of paper for each student

Procedure：

5 minutes- review topics discussed last class (genes, heredity, traits, alleles)- from slide #6

20 minutes: Present content via powerpoint slides 7-15. Order of ideas: dominant and recessive traits, homozygous and heterozygous traits, genotype, phenotype. Give time to take notes from powerpoint slides and have a couple minutes to review all the terms when finished with presentation.

10 minutes: Pop quiz, hand out paper and write question on the board and read to class “Using the words: genes, chromosomes, traits, generation, genotype, and phenotype, explain how characteristics of an individual are passed from parent to offspring.”

Give students 5-10 minutes to work on answer individually.

5 minutes: Exit slip: collect papers answer question as a class as an exit slip question

Assessment:

Exit slip question, quiz performance. Quiz will be graded out of 10

Lesson Plan- Day 3: Reproduction and Heredity

Standards:

2.1d In asexually reproducing organisms, all the genes come from a single parent. Asexually produced offspring are normally genetically identical to the parent.

2.1e In sexually reproducing organisms, the new individual receives half of the genetic information from its mother (via the egg) and half from its father (via the sperm). Sexually produced offspring often resemble, but are not identical to, either of their parents.

Objective:

By the end of the class period, Students will be able to define sexual and asexual reproduction, and the differences and similarities between them, and relate them to the concepts they have previously learned in the cell unit on mitosis and meiosis. Their knowledge is going to be demonstrated in a homework activity to be completed by the beginning of next class.

Materials: Powerpoint projector, meiosis/mitosis worksheet

Procedure:

5 minutes: review previous concepts: Genetics, genes heredity, chromosome, phenotype, genotype, dominant/recessive traits.

15 minutes: Present meiosis/mitosis powerpoint, starting off with the youtube video illustrating mitosis, making sure to emphasize that asexual reproduction uses mitosis and sexual reproduction uses mitosis. Crossing over in meiosis is responsible for genetic variation. Genetic variation in both types of reproduction; ask students how genetic variation is a good thing/ bad thing.

10 minutes: briefly go over the steps of mitosis and meiosis, which they should have learned in cell unit regarding cell division.

5 minutes: Introduce homework assignment, due next class period, and hand out meiosis and mitosis worksheet. Students may begin working on it and ask any questions. Make sure that they can refer to notes and textbook for answers.

5 minutes: Exit slip questions: What type of cell division does sexual reproduction utilize? Asexual? How many chromosomes does a normal body cell have in humans? Sperm cell? Egg Cell?

Assessment: Exit slip questions, homework assignment due next class period. To be graded.

Lesson Plan- Day 4: Chromosome Lab Activity

Standards:

Objective:

By the end of the class period, students will have demonstrated their knowledge of the role and arrangement of chromosomes and the different traits that they carry by completing and hands-on activity. They will also be able to understand the genetic basis for many of the common diseases.

Materials:

Chromosomes handout, male/female karyotypes, colored pencils

Procedure:

5 minutes: Review: Chromosomes, what do they contain (genetic information), how many chromosomes does a human have? Sexual/asexual reproduction?

5 minutes: Introduce activity: Have student read direction out loud, clarify information, state expectations, make sure students know that this must be completed before end of class. They may work with partner but each have to turn in his/her own work.

30 minutes: Students work on activity, make sure they stay on task. Collect on the way out. During this time, ask some questions like what chromosome is the trait cleft lip found? Is it dominant and recessive? Make sure materials are cleaned up at the end of class, desks back in order before anyone leaves.

Assessment:

Correctness of labels and completion of activity.

Ability to follow directions and participation.

Lesson Plan- Day 5: DNA: The Blueprint for Life

Standards:

2.1g Cells store and use coded information. The genetic information stored in DNA is used to direct the synthesis of the thousands of proteins that each cell requires.

Objective:

Students will understand the purpose, composition and chemical makeup of DNA and its location within the cell. They will begin an activity on modeling DNA in class, to be completed after the next lesson, demonstrating their knowledge of base pairing; as well introducing them to DNA replication.The activity will introduce students to DNA. DNA is a complex molecule that is found in all living organisms. The students will be able to manipulate the nucleotides ( basic building blocks ) of DNA.

Materials:

Powerpoint projector, cutouts of basic subunits of DNA, scissors, tape or glue, envelopes

Procedure:

5 minutes: Review: Chromosomes, what are they made out of? Introduce DNA as the building blocks of like and the most basic form of genetic information.

20 minutes: present information from slideshow (slides #16-23), make sure students understand that DNA is composed of sugar and base, the base pairings, give time for them to copy down slide, genes are segments of DNA that contain the information to be made into proteins.

5 minutes: Introduce activity, hand out worksheets, go over instructions. Hand out scissors so students can cut out the base pairs before the end of class. Hand out envelopes so students can write their names on them and put the cutouts inside for next class.

10 minutes: Students work in partners to cut out bases make sure that all are cut out and are in the envelopes for next class. Have them write their names on the envelopes. Material are collected before dismissal.

Before students leave, check understanding of DNA, base pairs- exit slip question

Assessment: Class participation, exit slip question

Lesson Plan- Day 6: Function of DNA

Standards:

2.1g Cells store and use coded information. The genetic information stored in DNA is used to direct the synthesis of the thousands of proteins that each cell requires.

Objective:

By the end of the class period, students will know that DNA is stores the code in by which proteins are synthesized, they will know that proteins are the functional components within the cell and the human body and they will demonstrate this by completing the activity modeling DNA.

Skills: Using tools, modeling, visualizing

Materials: Powerpoint projector, cutout of bases from last class period, scissors, tape or glue, construction paper

Procedure:

5 minutes: review previous class material, what is the blueprint for life? How do the bases pair up together in a DNA molecule? What shape is a DNA molecule?

15 minutes: Present new material (slides 24-29) make sure students have notes written down. Remind them of upcoming unit test. Emphasize the process from DNA-> RNA -> Proteins (Central Dogma)

5 minutes: Hand out material for the modeling DNA project. Remind students what the goal is and that it must be finished before the end of class.