|
Objectives |
Learning
Activities
|
Resources
|
|
Chromosomes, Genes, Alleles and
Mutations
|
|
| 3.1.1 State
that eukaryote chromosomes are made of DNA and protein
3.2.1 State
that meiosis is a reduction division in terms of diploid and
haploid numbers of chromosomes
3.2.2 Define
homologous chromosomes.
3.2.3 Outline
the process of meiosis, including pairing of chromosomes
followed by two divisions, which results in four haploid cells.
3.2.3 Outline
the process of meiosis, including pairing of chromosomes
followed by two divisions, which results in four haploid cells.
3.2.4 Explain
how the movement of chromosomes during meiosis can give rise to
genetic variety in the resulting haploid cells |
See topic 2 -
biochemistry. - Revision of DNA and Chromosomes structure.
Meiosis
Meiosis reduces the number of chromosomes. Meiosis is cell division used to produce gametes. Use
the meiosis bead kits to make a homologous pair of chromosomes
each with two chromatids. This is the appearance of the
chromosomes at the beginning of meiosis.
Write a description of the stages of meiosis.
Pay particular attention to the shape, position, and number of
chromosomes at each stage
Timed Meiosis Puzzle. Unscramble the meiosis models as
fast as you can. Add your time to the class list. Meiotic Medals
for the first three.
Make a Plastecine animation of meiosis - using Windows
Movie Maker - and add a live narrations.
Start with 2 homologous pairs of chromosomes each with two
chromatids.. Little
meiosis web movie here.
Variation...........
|
(Little
movie of DNA replication.)
Do
this web puzzle.
Try to include "independent segregation" of
chromosomes and "crossing over" of chromatids.
Key words:
- diploid, haploid,
- reduction division,
- crossing over,
|
|
3.2.5 Explain
that non-disjunction can lead to changes in chromosome number,
illustrated by reference to Down's syndrome (trisomy 21).
3.1.4 & 5 Define : Gene, Allele, Genome, gene mutation,
3.1.6 Explain
the consequence of a base substitution mutation in relation to the
process of transcription and translation, using the example of
sickle cell anaemia
|
When Meiosis Goes Wrong
eg Downs Syndrome
Make your own notes on the definitions
Use this webpage to help you to answer a difficult IB past
paper question - Mutation
Explanation of Sickle Cell Anaemia
|
|
|
3.1.2 State
that in karyotyping, chromosomes are arranged in pairs according
to their structure
3.1.3 Describe
one application of karyotyping.
|
Introduction to the Human
and the Mouse Karyotype
Try out the technique of Karyotype
analysis demonstrated by Dominique. Remember that
patience and care are the keys to success.
Key points:
- Chromosomes can be stained (with Trypsin) to show banding.
- This banding is very useful to find homologous pairs of
chromosomes.
- Karyotyping like this is used to screen mothers over 38
for trisomy or other congenital
defects in chromosomes and also to check the karyotype
of unborn babies.
|
Write an explation of
how you did the Karyotype.
Answer the questions,
- "When do doctors ask for a karyotype analysis?
- What can be found out from this type of test on
- a) parents and
- b) fetal cells from the amniotic fluid ?
|
|
3.2.6 State
Mendel's law of segregation.
3.3.6
Outline how the sex chromosomes determine gender
|
Click This link www.ensembl.org and
surf the human genome to find genes on a selection of
chromosomes. Here is the worksheet.
Gregor Mendel developed two very
important laws of heredity in the late 1800s in a monastery in Czechoslovakia.
Read pages 436-7 of Fullick Advanced
Biology.
and read this brief description of
Mendel's work
Write an account of Mendel's law
"Segredation of Characteristics".
Watch this Inheriting Gender
flash animation and write a short "outline" of how the sex
chromosomes determine your gender.
|
HL - need to also know Mendel's
law "Independant Assortment"
Mendel's
Laws with a genetic example.
|
|
3.3.1 Define:
Genotype, phenotype, dominant, recessive, Co-dominant, Locus, homozygous,
heterozygous, carrier, test cross.
3.3.2 Construct
a Punnett grid
3.3.3 Construct
a pedigree chart
3.3.4 State
that some genes have multiple alleles.
3.3.5 Describe
ABO blood groups
|
Theoretical Genetics
Read "Heredity", chapter 22 of Mackean IGCSE Biology.
This will reinforce the things you have already learnt. Pay
particular attention to the words in bold type which you need to
understand. Make yourself a glossary for each of these key
words.
DON'T COPY.- work out what the word means first, then write the
definition without looking back at the book.
Now scan through the first two pages again and answer questions 1 -
6 on page 211.
Check your answers here.
Extra Work in Mackean
|
Animation Activities:
- Fertilization & Alleles
- Inheritance of Ear lobes
- How the CF allele does it's damage
How do Genes Change how we are?
Brilliant revision
activity on Protein Synthesis
Revision
Quiz on Transcription and translation etc.
Protein
Synthesis -(revision - it's so important you know this)
Transcription
Translation
|
|
3.3.7
State that some genes are present on the X chromosome and absent
from the shorter Y chromosome in humans.
3.3.8
& 9Define sex linkage & states two examples.
3.3.10
State that a human female can be homozygous or heterozygous with respect
to sex-linked genes.
3.3.11
Explain that female carriers are heterozygous for X-linked
recessive alleles.
3.3.12
Calculate and predict the genotypic and phenotypic ratios of
offspring of monohybrid crosses
3.3.13
Deduce the genotypes or phenotypes of individuals in pedigree
charts
|
Presentation
Titles
on sex linkage
and other points about genetics
Theoretical
Genetics -other interesting cases. Some phenotypes don't fit the
theory so well because they are caused by:
|
Finally
lets use this knowledge in some humane breeding experiments.
- Click
here and answer the questions after you have bred some virtual
mice.
- Try some games to test your knowledge
.
|
|
3.4.1
State that PCR (polymerase chain reaction) copies and amplifies DNA.
3.4.2
& 3
State that gel electrophoresis involves the separation of
fragmented pieces of DNA according to their charge and size and is used in
DNA profiling.
3.4.4
Describe two applications of DNA profiling
3.4.5
& 6 Define Genetic screening and discuss three
advantages or disadvantages.
3.4.7
State what the Human Genome Project is, and two possible
advantagous outcomes of it.
3.4.9
State that genetic material can be transferred between species
because the genetic code is universal
3.4.10
Outline a basic technique used for gene transfer involving plasmids.
3.4.11
State two examples of the current uses of genetically modified
crops or animals
3.4.12
Discuss the potential benefits and possible harmful effects of one example of genetic
modification.
3.4.13 Outline
the process of gene therapy
3.5.1
Define Clone
3.4.15 Outline
a technique for cloning
3.4.16
Discuss the ethical issues of cloning in humans.
|
Genetic Engineering and Biotechnology
Read and make
notes on what are PCR, gel electrophoresis, & restriction endonuclease
enzymes, and how they work.
DNA profiling simulation. Chromatography
expt
Set up the Gel Electrophoresis cells with the inks and run
this for about 4 hours.
Experiment Details
What is genetic screening, give two examples (eg Biobank) and explain 3
advantages and disadvantages.
What
is the Human genome project,
One application of the Human Genome project is to identify faulty genes
that cause disease = Mutation
Explanation of Sickle Cell Anemia
Genetic Engineering: How
to make GMO to make insulin
Simplified Summary Insulin
IB
question about benefits and harmful effects.
Genetic Engineering Animations
here
Gene Therapy- what is it
Cloning
- what is it?
Answer these questions about
cloning.
Ethical issues - past paper
question
|
Yoghurt making
Explanation
of Chromatography
You tube explanations of
Biotechnology
www.dnai.org excellent activities on
DNA profiling > manipulation
ALSO origami
Complete the Questions on DNA Profiling
("fingerprinting") Collins p62-63.
Check
your answers here
Online
Forensics
Problems.to revise DNA profiling, genetic fingerprinting, gel
electrophoresis and PCR.
NOVA
explore human DNA
Gene
Tools Website
GM foods: http://scope.educ.washington.edu/gmfood/
transgenic
plant animation
Interesting
Article about chosing the sex of your baby. With opinions of a variety
of people for and against. Great for a debate.
Play the Food
Future Game
http://www.bbc.co.uk/genes/
|
| Extra Resources |
* Revision
Questions of Genetic Engineering &
Biotec for SL *
Brilliant
list of Genetics links
Good genetics
links
This
is a very thorough IB syllabus for SL and HL with lots of links
|
Use the self assessment
sheet to assess yourself as you do this section.
|