Alleles are
- different molecular forms of a gene
- heterozygotes
- different phenotype
true breeding homozygotes
The Correct Option is A
Approach Solution - 1
Genes are the units of inheritance and contain the information that is required to express a particular trait in an organism. Alternating forms of a single gene that code for a pair of contrasting traits are known as alleles. For example, two alleles determine the height of the pea plant (tall and dwarf). Principles of Inheritance and Variation 343 shape-Round (R)-Wrinkled (r).
Alleles are variations or forms of the same gene located at a specific chromosomal site. Alleles are generally present in pairs and control the same character or trait. Therefore, we can say alleles are an alternative form of a gene.
Approach Solution -2
The most effective oxidizer is Fluorine, having the biggest (+) electrode potential. Fluorine is the most powerful elemental oxidizing agent.
This happens because fluorine is the most electronegative element in the current periodic table, and hence has the highest active force on electrons of all the ingredients.
Oxidizing agents are normally located in their most oxidized states. Ions, atoms, and molecules with high electron affinity are known as good oxidizers. The bigger the oxidizing power, the stronger the electron affinity.
Oxidizing materials can increase the spread of fire and make it more strong. Substances that don't normally burn well in the air are able to burn quickly. Without visible elements, fuel materials are stimulated to fire at random.
Hence, the correct option is (D) F
Top Questions on Principles of Inheritance and Variation
- The inheritance of the AB blood group in humans is an example of -
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The sequence of nitrogenous bases in a segment of a coding strand of DNA is
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Concepts Used:
Principles of Inheritance and Variation - Mutation
A Mutation is a change in the sequence of our DNA base pairs caused by numerous environmental stimuli such as UV light or mistakes during DNA replication. Germline mutations take place in the eggs and sperm and can be passed onto offspring, whereas somatic mutations take place in body cells and are not passed on.
Types of Mutations
There are three types of mutations, which are as follows:
Silent mutation
It refers to any change in DNA sequence that has no effect on the amino acid sequence in a protein or the functions that a protein performs. There is no phenotypic indication that a mutation has occurred.
Nonsense mutation
When there is a change in the sequence of base pairs due to a point mutation, that results in a stop codon. This leads to a protein that is either shortened or non-functional.
Missense mutation
A missense mutation occurs when a point mutation causes a change in the codon, which then codes for another amino acid.
The mutation is caused by the following factors:
Internal Causes
When DNA copies incorrectly, the majority of mutations occur. Evolution occurs as a result of all of these mutations. DNA makes a copy of itself during cell division. When a copy of DNA isn't flawless, it's called a mutation since it differs somewhat from the original DNA.
External Causes
When certain chemicals or radiations are used to break down DNA, it causes the DNA to break down. The thymine dimers are broken by UV radiation, resulting in altered DNA.