Cephalonchordates are endotherm or ectotherm

Answer 1

An ectotherm, from the Greek εκτός (ektós) "outside" and θερμός (thermós) "hot", refers to organisms that control body temperature through external means. For example, many reptiles regulate their body temperature by basking in the sun. The opposite of ectothermy is endothermy, where heat is primarily generated as a result of internal metabolic processes.

Many ectotherms are also poikilotherms, meaning their temperature varies over a wider range than homeotherms.

Ectotherms are animals that warm their bodies by absorbing heat from their surroundings. In most ectotherms, the body temperature fluctuates with changes in the surrounding temperature; these ectotherms are called poikilothems. The body temperature of snakes, for example, cools in cold weather and warms up in hot weather. However, most marine fishes and invertebrates live in water that stays at constant temperature. Their body temperature, therefore, does not change, and these ectotherms are therefore considered homeotherms.

Answer 2

Ectotherm

Answer 3

ectothermic