Question

4. IS THE METHOD OF LOCOMOTION USED BY EACH SPECIES REFLECTED IN THE INTERNAL ANATOMY? EXTERNAL ANATOMY? GIVE EXAMPLES (6PTS) DOGFISH TURTLE MINK INTERNAL EXTERNAL 5. ALL SPECIES DISSECTED HAVE A FOUR CHAMBERED HEART. WHAT ARE THE CHAMBERS FOR EACH SPECIES? SPECIFIC MODIFICATIONS? WHAT DOES THE MORPHOLOGY FOUND IN THE HEART REFLECT? (7PTS-4 FOR STRUCTURES/3 FOR EXPLANATION MINK DOGFISH TURTLE 6. HOW DO THE REPRODUCTIVE STRUCTURES OF THE MINK AND DOGFISH COMPARE? HOW DOES THIS REFLECT THEIR TYPE OF REPRODUCTION? (3PTS) Mink

Please answer in full answers please.

Answer 1

1. Dogfish (Squalus acanthias)

Internal Anatomy:- Large quantity of oil is stored in the liver that provides buoyancy. As oil is less dense than water, storing oil decreases the overall density of the fish and helps in providing the uplift force. Also, relatively light skeleton is present in sharks that help to float and less amount of energy is required in swimming.

External Anatomy:- Fins and tail are the major organs contributing to locomotion in dogfish. In sweeping motion, caudal fin is moved from side to side. Forward thrust is provided by the large upper lobe of the caudal fin. Well developed lower caudal fin lobe provides greater thrust for high-speed swimming. Pectoral fin is used to change direction.

2. Turtle (Testudines)

Internal anatomy:- Lung ventilation affected by locomotion. Abdominal muscles, skeletal elements, and lungs have a relationship in locomotion.

External anatomy:- Pelvic fin is used to propulse through the water and pectoral flippers for maneuvering. When swimming, pectoral flippers are moved in a clapping motion underneath the body. For terrestrial motion, sea turtles either have diagonally opposite limbs moving together or contra-lateral limbs that move together.

Mink (Neovision vision):-

The primary means of locomotion is swimming.

Internal Anatomy:- Can undergo bradycardia to conserve oxygen while diving.

External Anatomy:- Streamlined body, ability to remain submerged for long periods, propulsion through large plantar surface. The undulating movement of trunk helps in moving forward while swimming.