Human Brain 

The human brain is the body's complex command center, con-trolling thoughts, senses, movement, and auto-matic funtions like breathing and heart rate, comprising the cerebrum, cere-bellum, and brainstem, protected by the skull and working via billions of interconnected nerve cells (neurons) to process and relay information throughout the nervous system. 

Key part & funtions

• Cerebrum: The largest part, divided into two hemispheres (left/right), responsible for higher functions like thingking, learning, memory, senses, and voluntary movement; its folded outer layar is the cerebral cortex. 

• Cerebellum: located at he back, it coordinates fine motor movements, posture, and balance.

• Brainstem: connects the cerebrum to the spinal cord, controlling essential automatic funtions like breathing, heart rate, sleep, and swallowing. 

                                             kidneys

The kidneys are two bean-shaped organs located below the ribs and an either side of spine. Their main function is to filter the blood and excerite waste and excwss water in the form of of urine. They also helps regulate blood pressure, control the production of red blood cells, and strengthen bones. 

Main functions of the kidney

• Waste removal: Filters harmful waste and excess water from blood to form urine.

• Blood pressure control: Makes harmons that helps control blood pressure.

• Hormone production: Produces hormone called erythropoitin of red blood cells.

• Strengthningbones: Helps convert vitamin D into its active form, which is essential for bone health.

• Maintaining balance: Maintains water mineral and acid-based balance in the body.

                                                             Heart 

The heart is a fist-sized muscular organ that pumps blood throughout the body throughout the body, delivering oxygen and nutrients to the tissues. It is located slightly to the left of the middle of the chest and is composed of four chambers (two atria and two ventricles). The heart is controlled by an electrical system and beats approximately 60-100 times a minute, increasing during physical activity. 

(some additional facts)

• The average adult heart weighs 280-340 grames (male) or 230-280 grames (female).

• An adult's heart pumps about 7,500 liters of blood a day. 

• At rest, an adult's heart beats approximately 60-100 times per minutes, while a newborn's heart may beat 90-190 times per minute. 

• lifestyle factors such as diet and exercise affect heart health.