Key concepts in plant genetics

Intriguing genetics questions about all plants

What is a plant?

Any of various photosynthetic, eukaryotic, multicellular organisms of the kingdom Plantae
characteristically producing embryos, containing chloroplasts, having cellulose cell walls,
and lacking the power of locomotion.- 1

The kingdom Plantae includes organisms that range in size from a tiny moss to a giant tree.
Despite this enormous variation, all plants are multicellular and eukaryotic (i.e., each cell
possesses a membrane-bound nucleus that contains the chromosomes). They generally
possess pigments (chlorophylls a and b and carotenoids), which play a central role in
converting the… 2


Plants are a major group of life forms and include familiar organisms such as trees, herbs,
bushes, grasses, vines, ferns, mosses, and green algae. About 350,000 species of plants,
defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently.
As of 2004, some 287,655 species had been identified, of which 258,650 are flowering
and 15,000 bryophytes (see table below). Green plants, sometimes called metaphytes,
obtain most of their energy from sunlight via a process called photosynthesis
. 3


What is a gene?

The basic unit in inheritance. There is no general agreement as to the exact usage of the term,
since several criteria that have been used for its definition have been shown not to be equivalent. 4

For any single trait

How many genes determine the trait?

Mendelian vs. quantitative inheritance

Where are these genes located?

Which genome(s)?

Nuclear genome

Which chromosome(s)?

What are the linkage relationships amongst these genes?

 

Considering trait combinations

Pleiotropy

Linkage

For all traits: How direct a relationship is there between genotype and phenotype?

Penetrance

Regulation

Transcription

initiation; transcript processing, transport

Translation

initiation, modification, transport


Epigenetics

Nova Science Now - Epigenetics

 

Genotype x environment interaction

 

Botanical and ethnobotanical considerations - Perspectives from Wambui

 

Genetics considerations - Perspectives from Dolores

 

Biotechnology - Perspectives from Sagar

 

 Plant profiles prepared by TA's:


Reading: Chapter 1

Featured plant genetics resource: Morex barley BAC clone sequence - NCBI DQ249273

Useful Links:

DNA Learning Center - from Cold Spring Harbor
Genetic Sciences Learning Center
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Kimball's Biology Pages
University of Nebraska Molecular Biology course resources