Why is corn good for studying genetics?
Corn is the ideal organism for introducing students to Mendelian genetics. Corn kernels express numerous phenotypes that are easy to recognize. The phenotypes typically used involve the color or shape of the kernel.
Which two traits are we going to observe in the corn ears?
In addition to kernel color, you will be observing kernel texture. The genes that control these two traits are found on separate chromosomes. The corn kernels observed may exhibit either a smooth or wrinkled phenotype.
What are the genetics of corn?
The colours of the corn kernels are inherited from the ‘parent’ plants. The corn kernels exhibit a large quantity of easy to recognise phenotypes through the colour and form. Purple corn results from a dominant allele, whereas yellow corn is produced by a recessive allele of the same gene.
Is smooth corn dominant or recessive?
This detail from an ear of corn illustrates the outcome of a dihybrid cross of parent plants that were heterozygous for kernel color and kernel form. P (purple) and S (smooth) are dominant alleles, and p (yellow) and s (wrinkled) are recessive alleles.
Why is maize a good model organism?
Invaluable as a food source, maize permeated Mexican culture and religion. Its domestication eventually led to its adoption as a model organism, aided in large part by its large chromosomes, ease of pollination and growing agricultural importance.
What color are the kernels on the parent ears of corn?
Student Sheet – Plant Heredity In corn, purple kernel (seed) color is dominant to yellow kernel color. Each kernel on the cob represents one of the offspring of the parents. By studying the kernels on an ear of corn, you can determine the genetic makeup and the appearance of the parents.
What are the dominant traits in the corn that we will be looking at in lab?
In this lab, we are going to look at two traits: kernel color and kernel texture. In corn, the dominant gene R determines the presence of colored aleurone.
Which genetic cross most likely produced your ear of corn?
dihybrid cross
Your Tentative Hypothesis: This ear of corn was produced by a dihybrid cross (PpSs x PpSs) involving two pairs of heterozygous genes resulting in a theoretical (expected) ratio of 9:3:3:1….
| Dominant Genes | Recessive Genes |
|---|---|
| P = Purple | p = Yellow |
| S = Smooth | s = Shrunken |
How many genes does corn have?
32,000 genes
The corn genome is a hodgepodge of some 32,000 genes crammed into just 10 chromosomes. In comparison, humans have 20,000 genes dispersed among 23 chromosomes. The $29.5 million maize sequencing project began in 2005 and is funded by the National Science Foundation and the U.S. departments of agriculture and energy.
How many gene pairs were responsible for the endosperm type and endosperm color in corn?
four genes
Summary of the four genes, Pr1, R1, C1 and Y1, influencing kernel color.
What determines seed shape in corn kernels?
Kernel size (small medium or large) and shape (round or flat) is determined primarily by the position of the kernels on the ear. Seed size and shape can also vary by hybrid and weather conditions during seed production, including temperature and rainfall.
What is the history of maize?
Maize (/meɪz/ MAYZ; Zea mays subsp. mays, from Spanish: maíz after Taino: mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago.