Biology, asked by madhavdcshop180502, 10 months ago

A pea plant having which of the given traits can express its feature only in pure line condition?​

Answers

Answered by Anonymous
0

Answer:

Mendel Gregor law

full explanation

Once upon a time (1860's), in an Austrian monastery, there lived a monk named Mendel, Gregor Mendel. Monks had a lot of time on there hands and Mendel spent his time crossing pea plants. As he did this over & over & over & over & over again, he noticed some patterns to the inheritance of traits from one set of pea plants to the next. By carefully analyzing his pea plant numbers (he was really good at mathematics), he discovered three laws of inheritance.

Mendel's Laws are as follows:

1. the Law of Dominance

2. the Law of Segregation

3. the Law of Independent Assortment

Now, notice in that very brief description of his work that the words "chromosomes" or "genes" are nowhere to be found. That is because the role of these things in relation to inheritance & heredity had not been discovered yet. What makes Mendel's contributions so impressive is that he described the basic patterns of inheritance before the mechanism for inheritance (namely genes) was even discovered.

Hail to the "Father of Genetics" !

My name is ma-ma-ma-ma-ma-Mendel.

There are a few important vocabulary terms we should iron-out before diving into Mendel's Laws.

GENOTYPE = the genes present in the DNA of an organism. We will use a pair of letters (ex: Tt or YY or ss, etc.) to represent genotypes for one particular trait. There are always two letters in the genotype because (as a result of sexual reproduction) one code for the trait comes from mama organism & the other comes from papa organism, so every offspring gets two codes (two letters).

Now, turns out there are three possible GENOTYPES - two big letters (like "TT"), one of each ("Tt"), or two lowercase letters ("tt"). Since WE LOVE VOCABULARY, each possible combo has a term for it.

When we have two capital or two lowercase letters in the GENOTYPE (ex: TT or tt) it's called HOMOZYGOUS ("homo" means "the same"). Sometimes the term "PURE" is used instead of homozygous.

When the GENOTYPE is made up of one capital letter & one lowercase letter (ex: Tt) it's called HETEROZYGOUS ("hetero" means "other"). Just to confuse you, a heterozygous genotype can also be referred to as HYBRID. OK?

Let's Summarize:

Genotype = genes present in an organism (usually abbreviated as two letters)

TT = homozygous = pure

Tt = heterozygous = hybrid

tt = homozygous = pure

PHENOTYPE = how the trait physically shows-up in the organism. Wanna know the simplest way to determine an organism's phenotype ? Look at it. Examples of phenotypes: blue eyes, brown fur, striped fruit, yellow flowers.

ALLELES = (WARNING - THIS WORD CONFUSES PEOPLE; READ SLOW) alternative forms of the same gene. Alleles for a trait are located at corresponding positions on homologous chromosomes.

Remember just a second ago when explaining genotypes I said that "one code (letter) comes from ma & one code (letter) comes from pa"? Well "allele" is a fancy word for what I called codes.

For example, there is a gene for hair texture (whether hair is curly or straight). One form of the hair texture gene codes for curly hair. A different code for of the same gene makes hair straight. So the gene for hair texture exists as two alleles --- one curly code, and one straight code.

Let's try & illustrate with a diagram.

In this picture the two "hot dog" shapes represent a pair of homologous chromosomes. Homologous chromosomes are the same size & have the same genetic info (genes). Each letter in the diagram stands for an allele (form of a gene). What's important to notice is that the letters can be in different forms (capital or lowercase) --- that is what we mean by allele --- and that the letters are lined-up in the same order along each hot dog --- I mean homologous chromosome. The "a-forms" are in corresponding positions, so are the "B-forms", the "c" alleles, the "d" alleles, etc. etc. OK?

Reread that "allele" definition again & study the picture.

Getting back to our abbreviations, we could use a "C" for the curly allele, and a "c" for the straight allele. A person's genotype with respect to hair texture has three possiblilties: CC, Cc, or cc. So to review some vocab, homozygous means having two of the same allele in the genotype (2 big or 2 little letters --- CC or cc). Heterozygous means one of each allele in the genotype (ex: Cc).

Now I could tell you which genotypes create curls & which do not, but then I'd be stealing some of Mr. Mendel's thunder. More on that in a minute ........

Answered by smartbrainz
0

Pea plant having recessive traits can express its feature only in pure line condition

Explanation:

  • The pea plant has different characteristics and the character is based on the two different allele which are present in the the pea plant for each character. If the two different allele are similar to each other they are said to be homozygous.
  • However if the two allele are different from each other they are said to be heterozygous..
  • in case of heterozygous condition the dominant trait is allowed to express itself. Only   recessive characteristics is able to be expressed when the character is homozygous recessive.

To know more about mendel's law of dominance,

State and explain the law of dominance with suitable example ..

.https://brainly.in/question/4892197

Similar questions