Stickleback Pelvic Development and Genetics

The video tutorial explores the three-spine stickleback fish, focusing on their unique spines and evolutionary adaptations. It discusses the differences between marine and freshwater sticklebacks, their habitats, and the genetic factors influencing their pelvic spine development. The video also covers the role of the pitx1 gene in spine growth and presents scientific experiments on crossbreeding sticklebacks to study phenotypic variations.

What is the primary habitat of the marine three-spine stickleback?

• Deep ocean trenches

• Freshwater lakes

• Inland coastal waters

• Tropical rivers

Why did freshwater sticklebacks evolve smaller pelvic spines?

• To conserve energy

• To attract mates

• To avoid predators in lakes

• To swim faster

What is the function of the pelvis in vertebrates?

• To connect the spine and legs

• To regulate body temperature

• To enhance sensory perception

• To aid in digestion

Which vertebrate has a pelvis adapted for climbing?

• Human

• Chimpanzee

• Mouse

• Fish

What are the building blocks of DNA?

• Proteins

• Lipids

• Adenine, Thymine, Cytosine, Guanine

• Carbohydrates

What role does the PITX1 gene play in sticklebacks?

• Controls fin size

• Instructs pelvic development

• Regulates growth rate

• Determines skin color

What was the result of crossbreeding marine and freshwater sticklebacks?

• Fish with different scale patterns

• Fish with larger fins

• Fish with medium pelvic structures

• Fish with no pelvic spines

What did scientists observe about the pelvic structures in crossbred sticklebacks?

• Symmetrical pelvic structures

• Asymmetrical pelvic structures

• No change in pelvic structures

• Increased spine length

How did the crossbreeding experiment help scientists?

• It revealed new fish species

• It helped study gene regulation

• It improved fish survival rates

• It increased fish population

What analogy is used to describe the crossbreeding experiment?

• Cooking a recipe

• Mixing colors

• Solving a riddle

• Building a puzzle