Chapter 10, Problem 21A

Summary Introduction

To replace:

The underlined words with correct vocabulary terminthe given sentence

Introduction:

Most of the species have diploid cells but some also have polyploidy cells. Such cells have one or more extra sets of chromosomes. For example there could be a triploid organism with 3n number of chromosomes. Polyploidy is rare in animals except in earthworms and goldfish. It is lethal in humans but is very common in flowering plants.

Answer to Problem 21A

Polyploidy has been used in agriculture to increase the size of flowers.

Explanation of Solution

Some common polyploidy plants are sugarcane ( 8n ), oats ( 6n ), and wheat ( 6n ). Commercial plants like strawberries and coffee are also polyploids. These plants have increased vigor and size. Having multiple sets of chromosomes affect the looks of a plant.

Plant geneticists develop new polyploidy species of plants that are more beneficial to humans. Such plants have larger and stronger, have better developed root system, and produce larger flowers and fruits. This feature of polyploidy is used by agriculture scientists to increase the size of flowers.

Hence, polyploidy is the correct word.