6th-Chapter 2: Lesson 2.1 Supporting and Moving the Body

Last updated 4 months ago
6 questions
15
Draggable itemCorresponding Item
muscular system
collection of organs that work together
joint
body system that covers and protects the entire body
integumentary system
outermost layer of the skin
hypodermis
middle layer of the skin, which contains hair follicles
dermis
innermost layer of the skin, which contains fat, blood vessels, and nerve endings; attaches to underlying bone and muscle
ligaments
body system made up of 206 bones that provides structure, shape, and protection to the body
skeletal system
location in the body where two or more bones meet and are held together
tendons
strong bands of tissue that hold together bones at joints to allow movement
epidermis
body system that helps the body move and aids other body systems
body system
structures made of tough tissue that connect muscle to bone
Required
15

Organization of the Body

The _______ is organized into _______ , _______ , _______ , and body systems (Figure 2.1). _______ are the basic unit of life. All living things, including the human body, are made of cells.

In the body, cells are organized as tissues. A _______ is a collection of similar cells that do a certain job for the body. For example, _______ is made of muscle cells. Muscle tissue can contract and shorten, enabling muscles to move.

Some tissues form glands. A _______ is a group of cells that produce and release substances into the body. For example, the _______ glands in the mouth release saliva. This liquid breaks down food so that it can be swallowed.
Tissues work together to form organs. An _______ is a collection of tissues that perform a specific job. For example, the stomach is an organ. Its job is to store and _______ . The stomach is made of several kinds of tissue, which include the following:
  • muscle
  • _______ tissue
  • _______ tissue
_______ work with other organs. A collection of organs that works together is a _______ . This chapter reviews most of the major body systems.

Each body system performs a set of important functions and makes up the human organism. Like the dimensions of health, body systems work very closely together. For example, the _______ and _______ systems work together so you can walk and run and move your arms. The respiratory and circulatory systems work closely together to bring air into the body and move it through the blood. Taking care of each system enables the others to work effectively.
Required
25

Integumentary System

The _______ system is one of three systems that support and move the body. The integumentary system includes the _______ , _______ , and _______ . It covers and protects the entire body and may be the most familiar body system. You see the integumentary system as you look at another person and when you look in the mirror. It is the only body system completely exposed to the world outside the body.


Skin

The _______ is the largest organ in the human body (Figure 2.2). If spread flat, the skin would cover _______ square feet, about the size of a bedsheet. Skin protects the body and does a surprising number of important jobs. Taking care of the skin ensures it can do these jobs. Some of the tasks the skin performs include the following:
  • keep out _______ that could infect the body
  • remove some waste and make _______ D to build strong bones
  • house nerve endings that allow people to _______ , touch, and pressure
The skin houses various nerves, pores, _______ , veins, and hair follicles. These items are housed within the three main layers of the skin: the epidermis, the dermis, and the hypodermis, as you saw in Figure 2.2.

The outermost layer of the skin is the epidermis. The epidermis, which consists of _______ of its own, is the thinnest layer of the skin. The main function of the _______ is to protect the body from infection by stopping foreign substances from entering into the body.

The middle layer of the skin is the _______ . This layer contains two proteins, collagen and elastin. These proteins provide support to the skin and give skin the ability to stretch and return to its normal shape. With age, the body creates less of these proteins, which leads to the appearance of wrinkles and sagging skin.

The innermost layer of the skin is the _______ . This layer consists of fat, _______ , and nerve endings. It also connects the skin to the bone and muscle underneath. Additional functions of each layer of skin are listed in Figure 2.3.

Hair and Nails

Hair and nails are made by cells in the skin. Both _______ are made of the protein keratin. Hair grows on all skin surfaces except the palms, soles, lips, nipples, and some areas of the genitals. Each hair grows from a specialized cell called a hair follicle. Hair, like the skin, helps _______ the body. For example, eyelashes and eyebrows shield the eyes. Nose hair prevents dust and particles from entering the airways. Head hair helps regulate temperature and protects the head from _______ .

_______ protect the ends of fingers and toes. They grow on the upper sides of fingers and toes near the ends. As they grow, the older _______ are pushed out, making the nails longer.
Required
15

Skeletal System

The _______ system is the body system made up of _______ that provides structure, shape, and protection to the body (Figure 2.4). For example, you can stand upright because of your sturdy and _______ backbone. You can walk because your _______ are strong and movable. The ribs protect the heart, lungs, and other internal organs. The _______ and _______ protect the brain and spinal cord. Bones also make movement possible when they are attached to muscles.

Bone Tissue

_______ develop, grow, and change throughout life. They are made of minerals, _______ , and living cells. Bone hardness comes from the minerals calcium and phosphate. Bone flexibility comes from the protein _______ . To envision bone tissue, think of a gelatin dessert with marbles in it. The marbles represent the hard _______ . The firm, flexible gelatin represents collagen. Together, the gelatin and marbles have hardness and flexibility, like bones.

Bones can grow and change because they contain living _______ . Some bone cells can make more bones. Other cells dissolve bones. Weight-bearing physical activities, such as _______ and lifting weights, put stress on bones. That stress pushes bone-making cells to make more bone tissue.
Required
15

Bone Structure

Bones come in many _______ and sizes (Figure 2.5). For example, bones of the arms and legs are long. Bones of the skull, _______ , and backbone are flat or have an irregular shape. Most bones have a dense outer tissue. Inside that dense tissue is a softer, _______ bone tissue. This spongy tissue contains cells that can make blood cells. The long bones of the arms and legs also have a hollow space filled with fat.

The ends of some bones are covered with _______ , which is not as hard as bone. The cartilage slowly turns into bone tissue until it is all used up, causing growth. This growth stops at different ages in different people. Some people stop _______ in their mid-teens. Others continue growing into their mid-twenties.

The _______ joint and other moving joints are kept moist by a special fluid. This _______ reduces the amount of friction between moving bones. It also cushions the bones that meet in the joint. In a _______ that moves, cartilage covers the bones’ surfaces. This tissue absorbs shock in the joint and protects the ends of the bones.
Required
15

Muscular System

The _______ system helps the body move and plays important parts in other body systems (Figure 2.6). For example, the skeletal and muscular systems work together to move the body. A _______ muscular system can help you achieve tasks and prevent injury.

Muscles are made of _______ tissue that can shorten and stretch. Muscle that is attached to a bone can make the bone move.

Muscles are _______ to bones by tendons made of tough tissues. Like muscles, tendons can shorten or lengthen. Muscles, bones, and tendons work closely together.

Muscle Tissue

Muscles are built from bundles of muscle cells. Different muscle cell arrangements create different types of muscle. Following are the three types of muscle tissue:
  • _______ are attached to bones and can be controlled. For example, you can choose to move your legs to walk or move them faster to run.
  • _______ cannot be controlled. These muscles do very important work without you realizing it. For example, the smooth muscles in your intestines digest food.
  • _______ is found in the heart. This muscle pumps blood through the body.

Muscle Pairs

Muscles can contract (become shorter and tighter) and relax. Most skeletal muscles contract to move the bones of the body. When muscles relax, body parts return to an original state. Throughout the body, most skeletal muscles work in pairs to move certain body parts. Some examples of muscle pairs include the following:
  • The _______ contracts to bend the arm at the elbow. The triceps muscle contracts to straighten the arm at the elbow (Figure 2.7).
  • The _______ contracts to bend the leg at the knee. The quadricep muscle contracts to extend the leg at the knee.
  • The _______ contracts to bend the leg at the hip. The gluteus maximus muscle contracts to extend the leg at the hip.