Chapter 2, The Genetic Basis of Plant Development Video Solutions, Plant Growth and Development

Problem 1

See Figs. 2.2 to 2.4 in answering both this question and Question 2. Acetabularia mediterranea and $A$. crenulata are different species belonging to the same genus. What are the morphological differences between them? How can you account for these differences and how do these differences come about?

Jennifer Stoner

Numerade Educator

03:03

Problem 2

When you graft an $A$. mediterranea rhizoid to an $A$. crenulata stalk, the graft will heal and the organism will regenerate a new cap. The first cap regenerated is intermediate in its morphology. Why?

Catherine M.

Numerade Educator

11:10

Problem 3

You have crossed a tall strain of peas that have terminal flowers with a strain having axial flowers and short stature. Both strains are true breeding when they are self-fertilized. What are the phenotypic characteristics of the F1 generation resulting from this cross? What are the genotypic and phenotypic characteristics of the F2 progeny obtained by self-fertilizing the $\mathrm{F} 1$ plants?

Khalida Dawar

Numerade Educator

04:42

Problem 4

Pea seeds that are homozygous $r r$ differ from those homozygous $R R$ in starch content, lipid content, and amount of legumin storage protein. Which of these is considered to be the primary effect of the gene and which is a pleiotropic effect? How does the genetic difference between these two plants bring this primary effect about? How can you account for these pleiotropic effects?

Khalida Dawar

Numerade Educator

09:10

Problem 5

What is the ratio of pigmented to colorless kernels in the ear of maize shown in Fig. 2.13A? How can you account for this ratio? In answering this question, you should remember that the pigmented aleurone phenotype is dominant over the colorless aleurone and that the aleurone is part of the endosperm, which is formed as a result of the fusion of two maternal nuclei with one male nucleus.

Khalida Dawar

Numerade Educator

09:10

Problem 6

How many different pigmented phenotypes can you detect in the kernels on the ear shown in Fig. 2.13B? How can you account for these differences when each kernel differs by only one allele?

Khalida Dawar

Numerade Educator

01:32

Problem 7

What is a homeotic gene? How is a homeotic gene different from a regulatory gene, such as those that regulate the anthocyanin biosynthetic pathway?

Hasnat Umar

Numerade Educator

01:42

Problem 8

Explain how differential growth could turn a spherical structure into a banana. Would this differential growth occur by cell division or cell enlargement?

Donald Albin

Numerade Educator