Lesson Plan - Get It!
Where do your muscle cells get the power they need to help you grow and move? Those tiny cells show how working together can accomplish more than by working individually!
Do you "feel the burn" after exercising?
That sensation is occurring in your muscle cells! You have muscles spread throughout your body, working to help you move, breathe, and grow. As discussed in another of our lessons, found under Additional Resources in the right-hand sidebar, there are three types of muscle tissue in your body: skeletal, cardiac, and smooth. Each type has a specific function to carry out in the body.
Before continuing, if you missed or need to review the four previous lessons in our Human Body Cells series, access them under Related Lessons in the right-hand sidebar.
- Skeletal muscles are found attached to the skeletal system and assist the body with movement. These specialized cells are long and thin with multiple nuclei. These many nuclei help the cell carry out the process of contraction and release, based on directions from the brain. Skeletal muscle cells have stripes on the outer membrane to assist with the contraction of the muscle. These cells look like thin fibers bundled together.
- Smooth muscle cells are much shorter than skeletal muscles and only contain one nucleus. These cells carry out involuntary functions, such as moving nutrients through the digestive system using contraction and relaxation.
- Cardiac muscle cells are found in the heart. These cells have a single nucleus and membrane strips to help contract during heart beats. They are long and branched together, creating a network of muscle cells.
All of these types of muscles help your body function daily. Muscle cells rely on an organelle called the "mitochondria." Mitochondria is considered the energy provider in animal cells because it converts food and sugar into cellular energy.
Adenosine triphosphate molecules are used to power cell processes, like cell transport. Muscle cells have many more mitochondria than other body cells because they are constantly converting sugar into energy for movement and muscle contractions.
- Have you ever felt fatigued or weak after having eaten less food?
This sensation occurs because your body is not providing enough energy to your muscles and body cells to function.
- Have your muscles felt sore the day after heavy exercise?
This is a chemical reaction that occurs in your muscle cells when there is a buildup of lactic acid. This molecule is produced during the process of changing food into energy during cell respiration. Muscle cells require oxygen to carry out respiration, and when the body can't supply muscle cells with enough oxygen, lactic acid builds up. It can cause painful cramps and aches the following day!
Your muscle cells are different from other cells in your body because they constantly utilize mitochondria to convert food into quick energy. The three types may differ in number of nuclei and cell structure, but they are all part of the muscular system that allows you to play and run!
- How might a reduction in mitochondria impact the function of muscle cells?
- Which type of muscle cell do you think has the most mitochondria?
Continue on to the Got It? section to exercise your intellectual muscles with in-depth research!