Question

Species and Breed Differences
- Different plant species grow at different rates even in identical conditions.
- Large cattle breeds grow _________________ than small breeds due to their _________________.

Seed Varieties
Different varieties of tomato or corn seeds grow at _________________ speeds.

Genetic Limits
Even with perfect conditions, an organism cannot grow beyond its _________________ potential.

Discussion Prompt
If two plants of different varieties receive the same water, sunlight, and soil, why might they still grow at different rates?

____________________________________________________________________________

____________________________________________________________________________

Environmental and Genetic Factors Working Together

Match each example to whether environment or genetics had the bigger effect:

Example 1: Drought decreases plant growth. Without water, even genetically strong plants cannot reach full size.

Effect: _________________ had the bigger effect.

Example 2: Fertilizer increases plant growth. Added nutrients help plants grow faster and larger.

Effect: _________________ had the bigger effect.

Example 3: Plant seed varieties grow differently. In identical conditions, different varieties still show different growth rates.

Effect: _________________ had the bigger effect.

Answer 1

Species and Breed Differences
- Different plant species grow at different rates even in identical conditions.
- Large cattle breeds grow faster than small breeds due to their genetics for larger mature size.

Seed Varieties
Different varieties of tomato or corn seeds grow at different speeds.

Genetic Limits
Even with perfect conditions, an organism cannot grow beyond its genetic potential.

Discussion Prompt
If two plants of different varieties receive the same water, sunlight, and soil, they might still grow at different rates because each variety has different genes that control growth rate, size, and how they use energy and nutrients. Varieties can differ in root structure, hormone levels, disease resistance, and the timing of developmental stages, so one variety may allocate resources to faster shoot growth while another invests more in roots or fruit. Seed quality or maternal effects can also cause differences even under identical external conditions.

Environmental and Genetic Factors Working Together

Example 1: Drought decreases plant growth. Without water, even genetically strong plants cannot reach full size.
Effect: Environment had the bigger effect.

Example 2: Fertilizer increases plant growth. Added nutrients help plants grow faster and larger.
Effect: Environment had the bigger effect.

Example 3: Plant seed varieties grow differently. In identical conditions, different varieties still show different growth rates.
Effect: Genetics had the bigger effect.