Studies of Identical Twins Have

question 63

Multiple Choice

Studies of identical twins have

• A)proved conclusively the importance of biological factors in human development.
• B)proved conclusively the importance of environmental factors in human development.
• C)proved conclusively that human development is a result of the interaction between environmental and biological factors.
• D)been based on extremely small samples and should be viewed as preliminary analyses at best.

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Definitions:

Improving Food Crops

The scientific and agricultural practice of modifying plant species to enhance their yield, nutritional value, and resistance to pests and diseases.

Plant Cells

Eukaryotic cells that are part of a plant, characterized by a cell wall, chloroplasts for photosynthesis, and a large central vacuole.

Stoma

Tiny openings or pores found on the surface of leaves and stems that allow for gas exchange between the plant and its environment.

Guard Cells

Specialized cells in the epidermis of leaves, stems, and other organs that regulate gas exchange and water loss by controlling the opening and closing of stomata.