Class interval should always be a whole number and yet in this case we have a decimal number. The solution to this problem is to round off to the nearest whole number. In this example, 2.8 gets rounded up to 3. So now our class width will be 3; meaning that we group the above data into groups of 3 as in the table below.
Skeletons come in a number of forms, each suited for a particular set of lifestyles and environments. Skeletons can be rigid, semirigid, or soft. They can also be external or internal. Vertebrates have internal skeletons, called bony skeletons, which consist mainly of calcified bone tissue. Most invertebrates, such as insects, spiders, and crustaceans, have outer skeletons called exoskeletons.
Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals.Bone tissue is a type of dense connective tissue. Bones have a complex internal and external structure making them lightweight, yet strong and hard.One of the types of tissue that makes up bone is mineralized osseous tissue. This tissue gives bone rigidity and a honeycomb-like three-dimensional internal structure.Other types of tissue found in bones include marrow, endosteum, periosteum, nerves, blood vessels and cartilage.The skeleton is an animalâs internal support frame.ther animals possess a skeleton on the outside of their body called an exoskeleton. Vertebrates. Vertebrates are animals that possess a vertebral column or âbackboneâ. This, along with the rest of the animalâs skeleton, comprises a support frame for the body and helps to protect vital organs.