Place the five gene pool containers in different locations throughout the room.When finished, ask students to place the features into the prepared gene pool containers (boxes, envelopes, etc.) labeled “Leaves,” “Fruit,” “Flowers,” “Roots,” and “Stems.” Provide each pair of students with a copy of the Plant Features activity sheet to color and cut out.Discuss dominant and recessive in terms of genes and heredity.Are there ways of making certain one person will always dominate (win)? Discuss the outcomes that students observed.Instruct the students to play Rock, Paper Scissors ten times and record the outcome of each round on the chart.Divide students into pairs, and provide each pair with a copy of the Rock, Paper, Scissors Recording Chart.Explain that rock dominates scissors, scissors dominate paper, and paper dominates rock. Describe the game Rock, Paper, Scissors using the words dominant and recessive.Today they will be learning about these traits. Explain that in genetics that are some traits that are dominant over others.Allow students to guess and to offer their ideas using their prior knowledge. Ask students if they can think of a connection between these two words (dominant and recessive) and genetics.Role-play a few situations, such as lining up after recess or participating in class discussions. The receding person may play at the slide later when there is less competition (similar to recessive genes). Another person might recede by walking away and playing somewhere else. For instance, if two people wanted to climb up the ladder of a slide at the same time, one person might dominate the situation by yelling or pushing the other person out of the way. Discuss the difference between dominating a situation and receding from a situation and provide examples.Have students list words that are associated with the terms dominant (dominated, dominating, dominate, domain, dominance, predominant, dominator, etc.) and recessive (recessively, recede, recess, receded, receding, recessional, recession, etc.).Yellow-kernel corn is dominant over white-kernel corn.Tall sunflower plants are dominant over short sunflower plants.Short and tall corn plants are co-dominant and produce medium height corn plants.Red and white snapdragon flowers are co-dominant and produce pink flowers.Red cherry tomatoes are dominant over yellow cherry tomatoes.Green peas are dominant over yellow peas.
#RECESSIVE AND DOMINANT TRAITS SKIN#
Russet-colored potato skin is dominant over white potato skin.
In agriculture there are many examples of dominant, recessive, and co-dominant traits. Plant breeders use knowledge of dominant and recessive traits to create new varieties of crop plants and ornamental plants. In this case, the two variations of the gene are expressed in equal strength. Co-dominance occurs when the genes for a particular trait are equally strong. When two recessive genes are combined, the recessive characteristic is expressed in the offspring. When a dominant gene combines with a recessive gene, the dominant gene’s characteristics are expressed in the offspring. In the simplest cases, genes are either dominant or recessive. Each parent contributes one-half of the genes for each trait. When plants and animals reproduce sexually, the traits of their offspring are determined by a combination of genes from each parent.
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