/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 16 Peas (Pisum sativum) are diploid... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 2: Problem 16

Peas (Pisum sativum) are diploid and \(2 n=14 .\) In Neurospora\(,\) the haploid fungus, \(n=7 .\) If it were possible to fractionate genomic DNA from both species by using pulsed field electrophoresis, how many distinct DNA bands would be visible in each species?

Short Answer

Expert verified
Peas show 7 distinct DNA bands and Neurospora shows 7 distinct DNA bands.

Step by step solution

01

Understanding the Diploid and Haploid Number

Diploid organisms have two sets of chromosomes, so if peas have a diploid number of 14, it means they have 7 pairs of chromosomes. Each pair represents a distinct band. For Neurospora, which is haploid, the haploid number given is 7, meaning it has 7 distinct chromosomes.
02

Determining Distinct DNA Bands for Peas

Since peas are diploid with a total of 14 chromosomes (2n=14), they have 7 pairs of homologous chromosomes. In a pulse-field gel electrophoresis, you generally see one band per pair, thus showing 7 distinct DNA bands.
03

Determining Distinct DNA Bands for Neurospora

Neurospora is a haploid organism with 7 chromosomes. In the electrophoresis, since it is haploid, each chromosome appears as a distinct band. Therefore, you would see 7 distinct DNA bands for Neurospora.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Diploid Organisms
In biological terms, diploid organisms are creatures that have two sets of chromosomes in their cells. This means that each type of chromosome is present in pairs, which is denoted as "2n."
For example, in peas (Pisum sativum), the diploid number is 14 (2n = 14), which indicates that they possess 7 pairs of chromosomes.
The presence of pairs allows for genetic diversity because each parent contributes one chromosome per pair, influencing traits and characteristics.
  • Each homologous pair in diploids can be different due to variations inherited from the parent's gametes, which helps in genetic variation.
  • Diploid states are common in many plants and animals, playing a crucial role in sexual reproduction by allowing for the mixing of genetic material from two parents.
Haploid Organisms
Haploid organisms have just one set of chromosomes in their cells, denoted by "n." As a result, they may be less genetically variable within an individual compared to diploid organisms.
For instance, in the fungus Neurospora, which is used often in genetics research, the haploid number is 7 (n = 7).
Without homologous pairs, haploids exhibit less complexity in chromosome structure but are still essential for processes like sexual reproduction.
  • Haploid cells are vital in the formation of gametes (sperm and eggs) where a single set of chromosomes is crucial so that upon fertilization, the offspring can restore the diploid state.
  • Many algae, fungi, and some plants spend a predominant part of their lifecycle in a haploid state, alternating to diploid during reproduction.
Pulsed Field Electrophoresis
Pulsed field electrophoresis is a sophisticated laboratory technique used for separating very large DNA molecules. Standard electrophoresis can't effectively separate large DNA fragments, but this method can, by varying the direction and strength of the electric field.
This process is particularly useful in observing the number of distinct DNA bands that represent different chromosomes in an organism.
  • In diploid organisms like peas, each homologous pair of chromosomes may result in one visible band per pair, leading to 7 distinct bands.
  • With haploid organisms, like Neurospora, having no pairs, each chromosome forms a separate band, resulting again in 7 distinct bands.
  • The technique's ability to toggle the electric field direction helps create a clearer separation based on size, allowing accurate analysis of large genomes.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Human cells normally have 46 chromosomes. For each of the following stages, state the number of nuclear DNA molecules present in a human cell: a. Metaphase of mitosis b. Metaphase I of meiosis c. Telophase of mitosis d. Telophase I of meiosis e. Telophase II of meiosis

A rare recessive allele inherited in a Mendelian manner causes the disease cystic fibrosis. A phenotypically normal man whose father had cystic fibrosis marries a phenotypically normal woman from outside the family, and the couple consider having a child. a. Draw the pedigree as far as described. b. If the frequency in the population of heterozygotes for cystic fibrosis is 1 in \(50,\) what is the chance that the couple's first child will have cystic fibrosis? c. If the first child does have cystic fibrosis, what is the probability that the second child will be normal?

In corn, the allele \(s\) causes sugary endosperm, whereas S causes starchy. What endosperm genotypes result from each of the following crosses? a. \(s / s\) female \(\times S / S\) male b. \(S /\) S female \(\times s /\) s male c. \(S / s\) female \(\times S / s\) male

Make up mnemonics for remembering the five stages of prophase I of meiosis and the four stages of mitosis.

A man's grandfather has galactosemia, a rare autosomal recessive disease caused by the inability to process galactose, leading to muscle, nerve, and kidney malfunction. The man married a woman whose sister had galactosemia. The woman is now pregnant with their first child. a. Draw the pedigree as described. b. What is the probability that this child will have galactosemia? c. If the first child does have galactosemia, what is the probability that a second child will have it?
See all solutions

Recommended explanations on Biology Textbooks

Biological Processes

Read Explanation

Bioenergetics

Read Explanation

Substance Exchange

Read Explanation

Biological Organisms

Read Explanation

Chemistry of Life

Read Explanation

Cell Communication

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.