Glands secrete chemical messengers called hormones directly into the bloodstream. These chemicals regulate slower, long-term body processes including metabolic rate, physical growth cycles, and reproductive development. 4. Transport and Defense
Your kidneys act as filters, cleaning your blood and removing waste products. The Protective Shield: Skin Integumentary System The Human Body
[External Stimulus] ➔ [Nervous System (Fast Electrical Signals)] ➔ [Immediate Reaction] ➔ [Endocrine System (Slow Chemical Hormones)] ➔ [Long-Term Adaptation] The Nervous System Transport and Defense Your kidneys act as filters,
Attached to this framework are over 600 muscles, which make up about 40% of your body mass. Muscles work on a principle of antagonistic pairs: the biceps contracts to bend the elbow, while the triceps contracts to straighten it. But muscle is more than a motor. Shivering is simply your muscles contracting rapidly to generate heat. The biggest muscle (by mass) is the gluteus maximus; the hardest working is the heart; and the smallest is the stapedius in the middle ear, which stabilizes the tiny bone that transmits sound. But muscle is more than a motor
To help expand this article,g., the brain, the digestive tract) and how the body fights them The impact of aging and lifestyle choices on human biology Share public link
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