Human Body Systems

1. Human Body Systems

2. Human Body Organization The Human Body is composed of Organ Systems are composed of Organs are composed of Tissues are composed of Cells

3. Circulatory System Major Structures • heart, blood vessels, blood, lymph nodes and vessels, lymph , blood cells Functions • transports nutrients, wastes, hormones, and gases Interactions with other systems • Nervous system : • The brain regulates heart rate and blood pressure. • Excretory • Cleans the blood • Respiratory system • Gas exchange in the lungs • Carbon dioxide and Oxygen

4. Cells of the Circulatory System • Red Blood Cells carry oxygen and carbon dioxide. • White Blood Cells attack and destroy germs in the body. • Platelets are bits of a blood cell that help stop bleeding. • Plasma is the liquid part of the blood. It includes salts, waste, nutrients, water, CO2 & O2

5. Digestive System Major Structures • mouth, throat, esophagus, stomach, liver, pancreas, small and large intestines Functions • extracts and absorbs nutrients from food; removes wastes; maintains water and chemical balances Interactions with other systems • Integumentary system • vitamin D activated in skin helps the absorption of calcium from digestive tract. • Reproduction system, • Adequate nutrients, including fats, are essential for conception and normal development. • Sequence of food pathway through system • Mouth, esophagus, stomach, small intestine and large intestine.

6. Food processing starts with ingestion (eating). • Teeth- mechanical digestion by masticating (chewing) food. 2. Upon entering esophagus, peristalsis (wave-like contractions) of smooth muscle carries the bolus (food ball) toward the stomach. 3. From the esophagus, bolus passes through a sphincter (muscular ring) into the stomach.

7. 7. Parts of the colon absorb water and minerals from undigested food and compact the remaining material into feces. 4. In the stomach, food undergoes chemical and mechanical digestion. • 5. Gallbladder contains Bile from liver that emulsifies (breaks into small particles) lipids (fats), which helps mechanical digestion of fats. • 6. Tiny villi (finger-like projections) cover walls of small intestine. This increased surface area causes more efficient food absorption

8. Digestive System What Benefits Do Gut Bacteria Provide? • Bacteria produce enzymes that digest polysaccharides in plant cell walls. Plants contribute to fiber in our diet for a healthy colon, but the enzymes released by good bacteria let us get the most nutrition from vegetables • Some digestive system bacteria make vitamin K and B group vitamins – (difficult to get from food) Humans can’t make these. Bacteria help maintain an optimum pH and stimulate the immune system. Gut bacteria breakdown drugs, hormones and cancer-causing environmental substances • Bacteria in the human gut are beneficial to their host, and enjoy a safe environment . The relationship is an example of mutualism.

9. Endocrine System Major Structures • hypothalamus, pituitary, pineal, pancreas, thyroid, parathyroid, adrenal, testes, and ovaries Functions • regulates body temperature, metabolism, development, and reproduction; maintains homeostasis; regulates other organ systems Interactions with other systems • Nervous system and circulatory system

10. Excretory System Major Structures • kidneys, urinary bladder, ureters, urethra, skin, lungs; Nephron- filtration unit of kidney Functions • removes wastes from blood; regulates concentration of body fluids Interactions • Circulatory system • Endocrine system

11. Immune System Major Structures • white blood cells, lymph nodes and vessels, skin, spleen Functions • defends against pathogens and diseases Interactions • Circulatory- delivers WBC’s where needed • Skeletal- makes WBC’s in red bone marrow

12. Cells of the immune system

13. What happens: • B cells recognize pathogens by the proteins (antigens) on their surface. • Helper T cells activate the B cells. • B cells divide to make plasma and memory B cells. • Plasma B cells produce antibodies that attach to the pathogen marking it for destruction. • Macrophages see the antibodies and eat pathogen cells • Memory cells are stored in the lymph nodes. They give a rapid immune response the next time the pathogen attacks.

14. Integumentary System Major Structures • skin, nails, hair, fat, nerves and blood vessels Functions • protects against injury, infection, production of Vitamin D, and fluid loss; helps regulate body temperature • Interactions with other systems • Immune system • First line of defense against infection • Nervous system • Complex network of nerves in skin send and receive impulses to and from brain, creating sense of touch. • Sense heat, cold, pain, pressure & touch

15. Cells of the Integumentary • Melanocyte- makes pigment (melanin) • Langerhans' cell- frontline defense for the immune system in skin • Adipose (fat) cells- provide insulation from heat and cold

16. Muscular System Major Structures • skeletal, smooth, and cardiac muscle tissues Functions • moves limbs and trunk; moves substances through body; provides structure and support Interactions with other systems • Skeletal system - provide skeletal movement • Digestive system- controls entrances and exits of digestive tract • Endocrine system- shiver to produce heat • Nervous system – helps sense of balance, pressure • Respiratory system- makes diaphragm contract & relax • Cardiovascular system – heart pumps to provide circulation

17. Types of Muscle Cells Cardiac Muscle cells - are branched and striped Skeletal Muscle cells - are striped and have many nuclei Smooth muscles- are pointed at both ends

18. Nervous System Major Structures • brain, spinal cord, nerves, sense organs Functions • regulates behavior; maintains homeostasis; regulates other organ systems; controls sensory and motor functions

19. Nerve Cells • Sensory (or afferent) neurons: send information from sensory receptors (e.g., in skin, eyes, nose, tongue, ears) TOWARD central nervous system. • Motor (or efferent) neurons: send information AWAY from central nervous system to muscles or glands. • Interneurons: send information between sensory neurons and motor neurons. Most interneurons are located in the central nervous system.

20. Reproductive System Major Structures • ovaries, fallopian tubes, uterus, and breasts (in females); testes and penis (in males) Functions • The male and female gonads (testes and ovaries) produce sex cells (ova and sperm) and the hormones necessary for the proper development, maintenance, and production of gametes and offspring

21. Egg Sperm Gametes of the Reproduction system

22. Respiratory System Major Structures • Nose, mouth, voice box (larynx), trachea, bronchi, lungs, alveoli (air sacs) Functions • moves air into and out of lungs; controls gas exchange between blood and lungs Interactions: • Circulatory system • Nervous system

23. Pathway: nose->pharynx->larynx-> trachea->bronchi-> Lungs-> bronchioles ->alveoli

24. Skeletal System Major Structures • Bones, joints and Bone marrow Functions • protects and supports body and organs; interacts with skeletal muscles; produces red blood cells, white blood cells, and platelets Interactions with other systems • Nervous System • Bones provide calcium needed for proper functioning of nerve cells • Circulatory system • Skeletal system protects internal organs and produces blood cells.

25. Cells of the Skeletal System Cells in the Bone that work with the Circulatory System