1.1 (test 1) Flashcards
What is artificial selection?
Artificial selection is the process of selective breeding of domesticated plants and animals with desirable traits.
Why wasn’t artificial selection always successful?
Sometimes parents chosen for their desired characteristics did not produce offspring with more or equally favorable qualities
What are two errors of selective breeding?
One parent contributes most to an offspring feature, which was often the male.
The concept of blended inheritance, where parental traits mix and forever change in the offspring.
What did Mendel experiment with?
Mendel experimented with pea flowers that have both sperm and egg-producing organs, making it easy to cross-fertilize or self-fertilize plants.
What is self-fertilization?
Self-fertilization occurs when both the egg and pollen (sperm) come from the same plant, often from the same flower.
What is cross-fertilization?
Cross-fertilization involves two plants. Mendel removed the stamens from one plant to prevent self-fertilization and brushed pollen from another plant onto the pistils of the first plant
What was an advantage of Mendel’s experiments?
Large numbers of individuals were obtained through a short growing season, allowing Mendel to observe clear inheritance patterns for traits like flower color and pea color
What did Mendel observe about traits?
Mendel observed direct traits like purple or white flowers, with no intermediates. This contrasts with continuous or discrete traits, like skin color or height, which have variations.
What specific traits did Mendel study in pea plants?
Mendel studied traits such as flower color (purple vs. white) and pea color (yellow vs. green).
What did Mendel observe inheritance of traits in pea plants?
Mendel saw clear inheritance patterns with distinct traits like purple or white flowers. There were no intermediate traits, only one or the other.
What are discrete or continuous traits?
Discrete traits, like Mendel’s flower color (purple or white), have clear options. Continuous traits, like human skin color or height, show variations in between extremes.
What is pure-breeding?
Pure-breeding occurs when plants self-pollinate and always produce offspring with the same traits as the parents, like white flowers only producing white flowers
What type of plants did pure-breeding plants produce?
Pure-breeding pea plants always produced offspring with the same traits as the parents when they self-pollinated. For example, a plant with white flowers always produced white flowers when self-pollinated.
What is meant by “antagonistic pairs” in Mendel’s experiments?
Antagonistic pairs are contrasting traits, such as purple and white flowers, where the plant can only have one of the two, not both
What are reciprocal crosses?
Reciprocal crosses are when Mendel reversed the traits of the male and female parents to control whether a trait came from the egg or sperm, proving equal contribution from both parents.
How did Mendel study pea plants?
Mendel crossed pea plants with different traits, like purple vs. white flowers. He observed how these traits showed up in the offspring, called hybrids. By tracking how traits were inherited, Mendel discovered patterns, like dominant and recessive traits.
What did Mendel’s mathematical approach involve?
Mendel studied how traits were passed down by working with large numbers of plants, analyzing the results mathematically to discover patterns of inheritance.
How did Mendel ensure his experiments were fair?
Mendel made sure that short plants were placed in the sunlight, not covered by tall plants, to ensure normal growth and fair, accurate results
