The Human Muscles. 8th Grade lesson

Hey guys. Here is the new lesson on Muscles. Enjoy!

Vocabulary:

within

cardiac

circulatory system

follicle

vessel

striation

branched

to contract

pacemaker

spindle

The Human Muscles

Learning Outcomes

Content: to be able to recall different types of muscle;

to be able to explain the function and structure of skeletal, cardiac muscle, and smooth muscle

Language: to be able to describe the function of each category of muscle

1 (pair work). Which element is important in contraction of muscle? Can you think of other things affecting your muscles?

1. sodium (Na+) 2. calcium (Ca++) 3. potassium (K+)

2 (individual work). True or False. Correct the false sentences. Use the text below.

A___There can be four types of muscles.

B___Walls of small intestine mainly made of a smooth muscle.

C___Pacemaker cells are found only in the heart.

D___Striated muscles work using two types of proteins: actin and myosin.

E___Skeletal and smooth muscle cells have one nucleus.

3 (individual work). Answer the questions.

1. What are functions of skeletal muscles?
2. What are differences between cardiac and smooth muscles organisation?

4 (team work). Discuss your answers.

Muscle is the tissue in human that allows active movement of the body or materials within the body. There are three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle. Most of the body’s skeletal muscle produces movement by acting on the skeleton. Cardiac muscle is found in the wall of the heart and pumps blood through the circulatory system. Smooth muscle is found in the skin, where it is associated with hair follicles; it is also found in the walls of internal organs, blood vessels.

Skeletal muscles maintain posture, stabilise bones and joints, control internal movement, and create heat. Skeletal muscle fibers are long and cells have many nucleuses. Muscle fibers are made of myofibrils. The striations are created by the organisation of actin and myosin resulting in the banding pattern of myofibrils.

Cardiac muscle is striated muscle that is present only in the heart. Cardiac muscle fibers have a single nucleus, are branched, and joined to one another by intercalated discs to hold the fibers together when the heart contracts. Contraction in each cardiac muscle fiber is triggered by Ca++ ions in a similar manner as skeletal muscle. Pacemaker cells stimulate the sudden contraction of cardiac muscle as a functional unit.

Smooth muscle is found throughout the body around different organs and tracts. Smooth muscle cells have a single nucleus, and are spindle-shaped. Smooth muscle can be stimulated by pacemaker cells, by the autonomic nervous system, by hormones, suddenly, or by stretching.

5 (individual work). This is the key vocabulary for the Muscles video. Use a dictionary to match the words with their translation.

to propel

to blink

thump

bundle

cilia

complementary

buccinator

to spread

6 (individual work). Answer questions after watching the Muscles video (https://goo.gl/gCc2qy)

A. Describe the functional difference between fast and slow twitch muscles.

B. What benefits does the muscular system provide, other than just helping you to move?

And watch THIS ONE at home