Genetics – the study of heredity. At the end of this topic you should be able to 1. Discuss the...
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Heredity and Gene Expression Genetics – the study of heredity
Genetics – the study of heredity. At the end of this topic you should be able to 1. Discuss the variation and diversity of organisms 2. Define the term
At the end of this topic you should be able to 1. Discuss the
variation and diversity of organisms 2. Define the term species 3.
Define the term heredity 4. Give an example of heredity 5. Define
the term gene expression 6. Example of a gene expression 7.
Definition of a gene 8. Outline the role of a gene 9. Know the
structure of a chromosome refer to DNA and protein structure
Slide 3
Variation means that there are differences between members of
the same species i.e. a population Think of all the variations
within your class even though you are all human
Slide 4
A group of organisms capable of interbreeding and producing
fertile offspring. Humans Cats Dogs Oak Trees Ash Trees
Males are sterile but female are fertile so not a new species
http://www.lifeinthefastlane.ca/wp-content/uploads/2007/10/tigons_sfw.jpg
Slide 10
Slide 11
What is meant by variation? Give the definition for species Why
is a liger not a new species?
Slide 12
Heredity is the passing on of features from parents to
offspring by means of genes Also called Genetic Inheritance
Slide 13
A gene is a length of DNA that codes for a specific protein It
is the unit of inheritance It is found on a chromosome It contains
instructions to make a particular protein It directly influences
the characteristics of an organism
Slide 14
Characteristics are controlled by genes. For example everyone
has genes which determine hair colour. But not everyone has the
same version of those genes. So there is more than one type of gene
for hair colour that you could have.
Slide 15
Not all genes are expressed Genes produce characteristics or
traits that are inherited Eg: Gene for Tallness Organism is small
Why? Maybe due to poor nutrition
Slide 16
Characteristics = heredity + environment
Slide 17
Heredity is the passing on of _________ from parents to
______________ by means of ______. A gene is the unit
__________________. They are found on a _________________. They
contain ________________ to make a particular _______________. Gene
expression is the way in which _____ ________ in a gene is
decoded.
Slide 18
Chromosomes contain a number of genes
Slide 19
Chromosomes are made up of 60% protein 40% DNA Genes are
arranged along the DNA of the chromosome
Slide 20
Large sections of the chromosome do not contain genes This DNA
is called Non Coding DNA Its function is not yet clear
Slide 21
Slide 22
Thread like structures Contain DNA Contain Protein Contain
Genetic Information Occur in pairs Found in the nucleus of all
cells
Slide 23
Can you . 1. Define the term heredity 2. Define the term gene
3. Outline the role of a gene 4. Define the term gene expression 5.
Know the structure of a chromosome