Muscular System

Muscle and Bone Movement

Muscular System

• There 630 active muscles in your body.• Muscles are bundles of cells and fibers.• Muscles tighten up, and then they relax.

Muscles

• Relax and contract to move bones

• Your muscles are all over your body

3 Types of Muscle:

1. Smooth Muscle

• cause your pupils to contract in the sunlight, visceral organs to contract.

• Is an Involuntary Muscle (moves without thought). Unstraited

Smooth

muscle fiber

Nucleus

Smooth Muscle

• One type of tissue, smooth muscle, is found in the walls of your internal organs and blood vessels

Smooth Muscle

• The most common function of smooth muscle is to squeeze, exerting pressure on the space inside the tube or organ it surrounds in order to move material through it. Large and Small

Intestine

2. Cardiac Muscle

• pumps heart.• Involuntary

Muscle and Straited

Cardiac muscle fiber

Striation

Nucleus

Cardiac Muscle

• Cardiac muscle is found only in the heart and is adapted to generate and conduct electrical impulses necessary for its rhythmic contraction.

Heart

30 sec muscle movement

Fact

• Our heart beats between 60 to 80 beats every minute, without having a break.

3. Skeletal Muscle

• move body. • Voluntary Muscle

and Straited

Skeletalmuscle fiber

Nucleus

Striation

• Muscles work in pairs. One contracts while another relaxes.

5 Structures of Muscle Tissue

Muscle car – Renault 2006

1. Filaments

• There are two types:• A. Thin - made of the protein actin.• B. Thick - made of the protein

myosin.

Muscle Filament

2. Sacromere

• a unit of thick and thin filaments.

3. Myofibril

• tiny cylindrical structures that makeup muscle fibers.

4. Bundle

• group of muscle cells are covered by sheath of connective tissue.

5. Muscle fibers

• have more than one nucleus to help relay messages faster. Triggered by nerve impulses.

• Remember muscle blocks from Chordates.

Trivia:

• Another word for sneezing is "sternutation."

Muscle

Doctors and misc Information

Types of Doctors / Medicine

• 1. Cardiology - heart• 2. Oncology - cancer• 3. Pediatrics - children• 4. Geriatrics - Aging• 5. Dermatology - skin• 6. Obstetrics - childbirth• 7. Orthopedics - bone

What does muscle strength depend on?

Answer

Muscle strength depends on the thickness of the muscle fibers and on how many of them contract at one time.

Question 1

Study the diagram. What part of the skin is number two referring to?

D. sweat pore

C. muscle

A. hair follicle

1 4 2

3 B. vein

Question 2

The answer is A, hair follicle.

1 4 2

3

What becomes the primary source of ATP production for your muscles during heavy exercise?

D. lactic acid fermentation

C. myosin

B. muscle contraction

A. cellular respiration

Question 3

The answer is D, lactic acid fermentation.

Blood Lactic Acid Levels During Exercise

Blo

od

lacti

c

acid

Work rate

Shift toward anaerobic process

What type of joint is used when you kick a soccer ball?

D. gliding

C. pivot

B. hinge

A. ball and socket

Question 4

The answer is B. Hinge joints are found in your knees and toes, both of which you use when you kick a soccer ball.

Hinge

What type of burn results in damage to the dermis and epidermis as well as blistering and scaring?

D. fourth-degree

C. third-degree

B. second-degree

A. first-degree

Question 5

The answer is B. Second degree burns can cause damage to the dermis and epidermis, but skin function is not lost.

What are newly formed bone cells called?

D. spongy bone

C. compact bone

B. osteoblasts

A. osteocytes

Question 6

The answer is A, osteocytes.

CapillaryOsteon systems

VeinArterySpongy bone

When does bone begin to replace cartilage in a human embryo?

D. at the 9th week

C. at birth

B. at the 12th week

A. during the last trimester

Question 7

The answer is D. Blood vessels penetrate the membrane covering the cartilage and stimulate its cells to become potential bone cells.