What is a vertebrate? (Keeping conditions stable ( the body temperature of…
What is a vertebrate?
Keeping conditions stable
the body temperature of most fishes, amphibians and reptiles is close to the temperature of their environment. In contrast, birds and mammals have a stable body temperature that is often warmer than their environment.
An endotherm is an animal whose body regulate its own temperature by controlling the internal heat produces. An endotherms body temperature usually does not change much even when the temperature of its environment changes. Birds and mammals are endotherms. Endotherms also have other adaptations, such as sweat glands, and fur or feathers for maintaining their body temperature. Because endotherms can keep their body temperature stable, they can live in a greater variety of environments than ectotherms can.
fishes, amphibians and reptiles are ectotherms. An ectotherm is an animal whose body does not produce much internal heat. It's body temperature changes depending on the temperature of its environment. Ectotherms are sometimes called cold-blooded. This term is misleading because their blood is often quite warm.
Characteristics of vertebrates
Most chordates are vertebrates. A vertebra is a backbone that is a part of an internal skeleton. This endoskeleton supports the body and allows it to move.
The backbone of a vertebra is part of its endoskeleton. This endoskeleton protects the internal organs of the body helps give the body shape and gives muscles of placed attached. In addition to the backbone, a vertebrate endoskeleton includes the skull and ribs. The skull protects the brain. The ribs attach to the vertebrae and protect the heart, lungs, and other internal organs. Many vertebrae Also have arm and leg bones Adapted for movement. An endoskeleton doesn't need to be replaced as the animal grows. Vertebrates can grow bigger than animals with exoskeletons or no skeletons at all.
A vertebrates backbone runs down the center of its back. A backbone is formed by many similar Bones called vertebrae. The vertebrae are lined up in a row like beads on a string. Joints or movable connections between the vertebrae, give the spine flexibility. Each vertebra has a hole in it that allows the spinal cord to pass through it. The spinal cord fits into the vertebrae like fingers fit into rings.
Characteristics of chordates
Most chordates are vertebrates. But a few chordates are invertebrates. At some point in their lives, chordates will have a notochord, a nerve cord that runs down their back and slits in their throat area.
Slits in the throat area
At some point in their lives chordates have slits in their throat area called pharyngeal slits, or gill slits. Some chordates including fishes keep these slits as a part of their gills for their entire lives. But in many vertebrates, including humans, pharyngeal slits disappear before birth.
nerve cord in back
in addition to having a notochord all chordates have a nerve cord that runs down their back. Your spinal cord is such a nerve cord. The nerve cord is the connection between the brain and the nerves on which messages travel back and forth. Many other groups of animals have nerve cord but their nerve cords do not run down their backs.
the phylum name chordate comes from the notochord, a flexible Rod that supports a chordates back. Some chordates have notochords all their lives. In contrast, in vertebrates, part of all of the notochord is replaced by a backbone