MUSCLES

Question 1

What do the muscles throughout the body do? At the simplest level, muscles allow us to move. Muscles allow for movement such as walking, and they also facilitate bodily processes such as respiration and digestion.

Question 2

The body contains three types of muscle tissue:

Answer 2

CARDIAC MUSCLE
SKELETAL MUSCLE
SMOOTH MUSCLE

Question 3

• forms skeletal muscles, which attach to bones and sometimes the skin and control Iccomotion and any other movement that can be consciously controlled. Because it can be con- trolled intentionally, skeletal muscle is also called voluntary muscle.
• When viewed under a microscope, skeletal muscle tissue has a striped or striated appearance.

-This appearance results from the arrangement of the proteins inside the cell that are responsible for contraction. The cells of skeletal muscle are long and tapered and have multiple nuclei on the periphery of each.

Answer 3

SKELETAL MUSCLE TISSUE

Question 4

Upper Body

Answer 4

 Cranium
 Clavical
 Sternum
 Scapula
 Ribs
 Vertebral
 Column

Question 5

Bones of the leg

Answer 5

 Femur
 Patella
 Fibula
 Tibia

Question 6

Bones of the foot

Answer 6

 Tarsals
 Metatarsals
 Phalanges

Question 7

enable movement and facilitate vital bodily functions.

Answer 7

MUSCLES

Question 8

voluntary and attached to bones for movement

Answer 8

SKELETAL MUSCLE

Question 9

which is involuntary and found in organs like the intestines and blood vessels

Answer 9

SMOOTH MUSCLE

Question 10

which is involuntary and exclusive to the heart.

Answer 10

CARDIAC MUSCLE

Question 11

Skeletal muscle fibers contain myofibrils made of actin and myosin proteins, which interact to produce contractions using ATP. In animals, structural body plans vary, such as the frog (a vertebrate with limbs for jumping), the cockroach (an insect with an exoskeleton), and the starfish (a radial invertebrate with tube feet). Anatomical terms help describe body structures, including symmetry (bilateral, radial, asymmetrical), directional terms (anterior, posterior, dorsal, ventral), and body planes (sagittal, frontal, transverse), which provide a framework for studying animal anatomy.

Question 12

It is an involuntary, non-striated muscle.

Consists of thick and thin filaments that are not arranged into sarcomeres giving it a non-striated pattern.

Answer 12

Smooth muscle

Question 13

occurs in the walls of hollow organs such as the intestines, stomach, and urinary bladder, and around passages such as in the respiratory tract and blood vessels.

Answer 13

SMOOTH MUSCLE

Question 14

Smooth muscle cells have a single nucleus and characterized by ______

Answer 14

spindle-shaped cells.

Question 15

• control how your eyes focus.

Answer 15

Eyes

Question 16

• regulating blood flow and pressure

Answer 16

Blood Vessels

Question 17

• regulating airway caliber and airflow, impacting breathing and ventilation.

Answer 17

Respiratory Tract

Question 18

• facilitates digestion and nutrient absorption.

Answer 18

Alimentary Canal

Question 19

• contractions during labor that efface and dilate the cervix and deliver the fetus.

Answer 19

Uterus

Question 20

• urine storage and voiding.

Answer 20

Urinary Bladder

Question 21

is a type of muscle tissue that forms the heart. It contains cardiac muscle cells, which perform highly coordinated actions that keep the heart pumping and blood circulating throughout the body.

Answer 21

CARDIAC MUSCLE TISSUE OR MYOCARDIUM

Question 22

are rectangular, branching cells that typically contain only one centrally-located nucleus. They are located in the walls of the heart.

It contracts and releases involuntarily and keeps the heart pumping blood around the body. Cardiac muscle cannot be consciously controlled and is called involuntary muscle.

Answer 22

Cardiomyocytes

Question 23

SKELETAL MUSCLE FIBER STRUCTURE

Each skeletal muscle fiber is a muscle cell.

Key Components:
 Myofibrils - long, cylindrical structures within muscle fibers.

 Sarcolemma - plasma membrane that connects to myofibrils.

 Striations - caused by alternating bands of actin (thin) and myosin (thick) filaments.

 Myofilaments:
-Thick Filaments - made of myosin.
-Thin Filaments - made of actin.

Question 24

SKELETAL MUSCLE FIBER FUNCTION

Sarcomere - functional unit of muscle contraction.

Contraction Process:
 Nerve signal triggers contraction.

 Sliding Filament Theory: Myosin heads bind to actin, pull, release, and repeat.

 Filaments do not shorten, but sarcomere contracts.

 ATP is required for myosin movement and muscle contraction.

 Muscle contraction occurs when multiple sarcomeres work
together.

Question 25

STRUCTURAL PLAN OF THE ANIMAL BODY The animal’s body is different from that of a plant’s body. It has provisions for locomotion (in most) and for food-getting. The frog belongs to Class Amphibia.  Three regions: head, trunk (without any neck) and appendages.  The adult has no tails but it has two pairs of limbs: the forelimbs and the hindlimbs.  Female frogs usually have a blunt snout and a smaller body than the males.  Only male frogs croak and, therefore, are the only ones with vocal sacs.

Question 26

The cockroach is a member of Class Insecta.  Three regions: head, thorax, and abdomen.  Lacks internal skeleton (endoskeleton), but has waxy chitinous exoskeleton for protection from mechanical injury.

Question 27

The starfish, also known as sea star, is a member of Class Asteroidea. - Has five or more arms radiating from a central disk depending on the species. - The undersurfaces bear the tube feet which function for locomotion, feeding and gas exchange. - The body of the starfish is composed mainly of calcium carbonate, known as the ossicles, that forms the endoskeleton which is covered by a thin epidermis. This endoskeleton takes on different forms, such as spines and granules.

Question 28

ANATOMICAL TERMINOLOGIES IN THE BODY PLANS Symmetry  Asymmetrical: Any animal or part of an animal that cannot be divided into two or more equal parts.

Question 29

Body or part divisible by one median into equivalent left and right halves, such that one is a mirror image of the other. Example: Sea turtle Butterfly Drosophila (fruit fly) Shark Lobsters Human

Answer 29

Bilateral

Question 30

Arrangement wherein equivalent parts are arranged around a common central axis. Ex: Starfish

Answer 30

Radial