Breaks down food mechanically and chemically.

Absorbs nutrients (like carbohydrates, proteins, fats, vitamins, and minerals) from food.

The digestive system interacts with the circulatory system by absorbing nutrients from digested food into the bloodstream. Nutrients are transported via blood vessels to various tissues and organs for energy, growth, and repair.

Transports oxygen, nutrients, hormones, and waste products throughout the body.

Facilitates gas exchange (oxygen and carbon dioxide) in the lungs.

Regulates body temperature and pH balance.

The circulatory system interacts with the respiratory system by transporting oxygen from the lungs to body tissues and removing carbon dioxide produced by cells. This exchange occurs via the blood vessels, ensuring oxygenation and cellular respiration.

Facilitates the intake of oxygen and removal of carbon dioxide through breathing.

Exchange of gases occurs in the alveoli of the lungs.

The respiratory system interacts with the endocrine system by regulating the levels of carbon dioxide in the blood. Elevated CO2 levels can trigger hormonal responses to regulate breathing rates and maintain proper blood pH levels.

Regulates bodily functions using hormones secreted by glands like the thyroid, adrenal, and pituitary.

Controls metabolism, growth, and development.

Maintains homeostasis by influencing various functions such as reproduction, response to stress, and energy levels.

The endocrine system interacts with the nervous system through the hypothalamus and pituitary gland. The hypothalamus sends signals to the pituitary gland, which then releases hormones that regulate other endocrine glands, coordinating responses to stress and regulating various bodily functions.

Provides support, structure, and movement through bones, muscles, tendons, and ligaments.

Protects vital organs and allows for bodily movement.

The musculoskeletal system interacts with the endocrine system through hormones like calcitonin and parathyroid hormone, which regulate calcium levels in bones. Hormonal imbalances can affect bone density and growth.

Controls and coordinates bodily functions and responses to stimuli through the brain, spinal cord, and nerves.

Enables sensory perception, cognition, and voluntary and involuntary actions.

The nervous system interacts with the immune system through neural pathways that regulate immune responses. Stress responses regulated by the nervous system can influence immune function, impacting susceptibility to infections or inflammatory conditions.

Defends the body against pathogens, infections, and foreign substances.

Recognizes and eliminates abnormal cells, including cancer cells.

Comprised of various cells, tissues, and organs working together to provide immunity.

The immune system interacts with the reproductive system during pregnancy to ensure immunological tolerance of the fetus. The immune system adjusts to not reject the developing fetus, balancing protection against pathogens while allowing for fetal development.

Responsible for the production of gametes (sperm in males, eggs in females) for reproduction.

Facilitates fertilization, pregnancy, and childbirth.

Produces hormones regulating reproductive processes.

The reproductive system interacts with the immune system to establish immune tolerance during pregnancy. The immune system must adapt to the presence of the fetus without considering it a threat. This interaction involves hormonal changes that modulate the immune response, preventing rejection of the developing fetus.