Nicotiana tabacum is presumed to be an allotetraploid originating from a cross between N. sylvestris (the S genome) and N. tomentosa (the T genome). Each of the two parental species (2n = 24) contributed 12 chromosomes (S & T), which then doubled to form the 24 pairs of chromosomes observed in N. tabacum. a) Diagram the entire cross starting with the original parents until the formation of N. tabacum. Distinguish between chromosomes of N. sylvestris and N. tomentosa and give the chromosome number of all individuals in the cross. Include gametes in your crosses. b) A monosomic N. tabacum is crossed with N. sylvestris and produces offspring, some with 36 chromosomes and some with 35 chromosomes. Using cytological examination at meiosis, the 35-chromosome types show 11 bivalents and 13 univalents. Is this plant monosomic in the S or T genome? Show why it cannot be the other genome as part of your solutions

Human Anatomy & Physiology (11th Edition)
11th Edition
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:Elaine N. Marieb, Katja N. Hoehn
Chapter1: The Human Body: An Orientation
Section: Chapter Questions
Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...
icon
Related questions
Question
Nicotiana tabacum is presumed to be an allotetraploid originating from a cross between N. sylvestris
(the S genome) and N. tomentosa (the T genome). Each of the two parental species (2n = 24)
contributed 12 chromosomes (S & T), which then doubled to form the 24 pairs of chromosomes
observed in N. tabacum.
a) Diagram the entire cross starting with the original parents until the formation of N. tabacum.
Distinguish between chromosomes of N. sylvestris and N. tomentosa and give the chromosome
number of all individuals in the cross. Include gametes in your crosses.
b) A monosomic N. tabacum is crossed with N. sylvestris and produces offspring, some with 36
chromosomes and some with 35 chromosomes. Using cytological examination at meiosis, the
35-chromosome types show 11 bivalents and 13 univalents. Is this plant monosomic in the S or
T genome? Show why it cannot be the other genome as part of your solutions
Transcribed Image Text:Nicotiana tabacum is presumed to be an allotetraploid originating from a cross between N. sylvestris (the S genome) and N. tomentosa (the T genome). Each of the two parental species (2n = 24) contributed 12 chromosomes (S & T), which then doubled to form the 24 pairs of chromosomes observed in N. tabacum. a) Diagram the entire cross starting with the original parents until the formation of N. tabacum. Distinguish between chromosomes of N. sylvestris and N. tomentosa and give the chromosome number of all individuals in the cross. Include gametes in your crosses. b) A monosomic N. tabacum is crossed with N. sylvestris and produces offspring, some with 36 chromosomes and some with 35 chromosomes. Using cytological examination at meiosis, the 35-chromosome types show 11 bivalents and 13 univalents. Is this plant monosomic in the S or T genome? Show why it cannot be the other genome as part of your solutions
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Similar questions
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:
9780134580999
Author:
Elaine N. Marieb, Katja N. Hoehn
Publisher:
PEARSON
Biology 2e
Biology 2e
Biology
ISBN:
9781947172517
Author:
Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:
OpenStax
Anatomy & Physiology
Anatomy & Physiology
Biology
ISBN:
9781259398629
Author:
McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:
Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:
9780815344322
Author:
Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:
W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:
9781260159363
Author:
Martin, Terry R., Prentice-craver, Cynthia
Publisher:
McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Inquiry Into Life (16th Edition)
Biology
ISBN:
9781260231700
Author:
Sylvia S. Mader, Michael Windelspecht
Publisher:
McGraw Hill Education