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The pigment that gives skin its color and protects against UV rays?
Melanin
This type of muscle is voluntary and attached to bones.
Skeletal Muscle
Body system that functions by secreting hormones directly into the blood
Endocrine
The tube that is part of both the urinary system and reproductive system in males
Urethra
These blood cells fight infection and are part of the body's defense system.
Leukocytes (White blood cells)
The type of bone marrow that produces red blood cells.
The main communication cells of the nervous system.
Neurons
The esophagus belongs to this body system
Digestive system
Structures that act as small filters that trap and destroy bacteria and cancer cells, other debris.
The main gas exhaled as waste.
Carbon Dioxide
The part of the skeleton that includes the skull, spine, and rib cage.
Axial Skeleton
This muscular sheet separates the chest cavity from the abdominal cavity.
Diaphragm
Pharynx belongs to this body system
Respiratory
Oil and sweat glands belong to this system.
Integumentary
This hormone regulates blood sugar by lowering glucose levels.
Insulin
The cells that produce bone.
Osteoblasts
The gap between neurons where neurotransmitters are released.
A synapse
Ureter belongs to this body system.
Urinary
Most nutrient absorption happens in this part of the digestive tract.
Small intestine
The windpipe that carries air into the bronchi
Trachea
A dense strap of regular dense fibrous connective tissue
A tendon
Skeletal
These glands sit on top of the kidneys and produce adrenaline.
Adrenal Glands
This type of muscle is found only in the heart.
Cardiac Muscle