Heredity and Gene Expression
Genetics – the study of heredity
Lesson Objectives
At the end of this lesson you should be able to
1.
Define the term heredity
2.
Example of heredity
3.
Define the term gene expression
4.
Example of a gene expression
5.
Definition of a gene
6.
Outline the role of a gene
7.
Know the structure of a chromosome – refer to DNA and protein structure
Heredity
Heredity is the ______________ ____ of features from ______________ to ________________
by means of __________
Also called - ______________ ______________________
Genes

A gene is a length of DNA that codes for a ________________ ______________

It is the unit of ______________________

It is found on a ______________________

It contains ________________________ to make a particular ______________

It directly influences the _____________________________ of an organism

Characteristics are controlled by __________.
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
For example everyone has genes which determine hair colour.

But not everyone has the ________ ______________ of those genes.

So there is ________ ________ ______ ________ of gene for hair colour that you
could have.
Gene Expression
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
Characteristics
Characteristics = ________________ + ______________________
Learning Check
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.
Chromosomes
Chromosomes contain a number of genes
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Chromosome Structure
Chromosomes are made up of
60% ______________
40% ______________
Genes are ________________ __________ ______ ______ of the chromosome.
Non Coding DNA
Large sections of the chromosome do not contain genes
This DNA is called ______ ____________ ______
It ’s function is not yet clear
Chromosome structure
Chromosomes

Thread like structures

Contain ______

Contain ______________

Contain ______________ ______________________

Occur in __________

Found in the _____________ of all cells
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What have you learned?
Can you …………….

Define the term heredity

Define the term gene

Outline the role of a gene

Define the term gene expression

Know the structure of a chromosome
En d
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