Jawless fish are typically classified as which blood type?

Jawless fish are typically classified as which blood type?

• A. Warm-blooded
• B. Cold-blooded
• C. Endothermic
• D. Homeothermic

Answer: (B)

Jawless fish rely on the surrounding water to set their body temperature because they do not generate enough metabolic heat to stay warm on demand. This lack of internal heat production places them in the cold-blooded category, also called ectothermic. Warm-blooded or endothermic animals produce metabolic heat and maintain a relatively constant internal temperature, which jawless fish do not do. Homeothermic animals keep a steady body temperature as well, another trait these fish don’t exhibit. So cold-blooded best describes jawless fish like lampreys and hagfish.

Jawless fish rely on the surrounding water to set their body temperature because they do not generate enough metabolic heat to stay warm on demand. This lack of internal heat production places them in the cold-blooded category, also called ectothermic. Warm-blooded or endothermic animals produce metabolic heat and maintain a relatively constant internal temperature, which jawless fish do not do. Homeothermic animals keep a steady body temperature as well, another trait these fish don’t exhibit. So cold-blooded best describes jawless fish like lampreys and hagfish.