Human Body Systems Flashcards: 11 Organ Systems, Organs & Functions
Study 105 cards on organization levels, 11 organ systems, representative organs, core functions, and homeostasis. This model counts integumentary separately and combines lymphatic/immune.
About this deck
Human Body Systems Flashcards: 11 Organ Systems, Organs & Functions
Build a practical overview of the human body before moving into regional anatomy. These 105 English flashcards start with cells, tissues, organs, organ systems, and homeostasis, then cover the main function and representative structures of each system.
The 11-system model
Anatomy resources do not all group the systems the same way. NCI SEER Training's introductory overview lists ten systems because it does not count the integumentary system separately. This deck uses a common introductory 11-system convention: integumentary; skeletal; muscular; nervous; endocrine; cardiovascular; lymphatic/immune; respiratory; digestive; urinary; and reproductive. It counts integumentary separately and combines lymphatic and immune functions.
What the cards practice
- Recall each system's main job.
- Connect representative organs and structures with their system or role.
- Use a limited set of bounded reverse prompts where producing the system or organ is genuinely useful.
- Explain a few clear homeostasis links, including movement, gas transport, fat absorption, temperature control, blood composition, sensation, and digestive propulsion.
The deck does not mechanically reverse every fact or treat shared organs as belonging exclusively to one system. The pancreas, gonads, diaphragm, skin, liver, and other cross-system structures are described by the role being reviewed.
Learning order
Organization levels come first. The cards then make repeated passes through all 11 systems: main functions before structures, and structures before selected reverse recall. Each system returns only after ten unrelated cards, so similar prompts do not cue one another. The final ten cards connect systems through homeostasis.
Scope
This is an introductory anatomy and physiology overview. It excludes diagnosis, treatment, clinical advice, detailed pathology, medical procedures, image-identification practice, exhaustive organ lists, and advanced pathway detail. It supports study but does not replace a full course, lab, or medical guidance.
Facts were checked primarily against the NCI SEER Training anatomy modules, with focused cross-checks from NIAMS on skin, NIAID on the immune system, and NIDDK overviews of digestion and the urinary tract.
The prompts, answers, sequence, metadata, and generated cover were independently created from common knowledge and original work. No competitor cards, textbook prose, source figures, logos, or third-party media were copied.
The Common knowledge · CC0 1.0 label applies to the original wording, organization, metadata, and cover to the extent applicable rights exist. It does not claim ownership of anatomical facts.
Source review date: August 31, 2026.
Cards in this deck
Card 1
Question
Why can two anatomy resources give different counts for the body's organ systems?
Answer
Classification conventions vary. This deck uses 11 systems by counting the integumentary system separately and combining lymphatic and immune functions.
Card 2
Question
What is the usual order of biological organization from simplest to most complex in the human body?
Answer
Cells → tissues → organs → organ systems → organism.
Card 3
Question
What is a cell in the body's organization hierarchy?
Answer
The basic living unit of the body.
Card 4
Question
What is a tissue?
Answer
A group of similar cells, together with their surrounding material, organized to perform a shared function.
Card 5
Question
What is an organ?
Answer
A structure made of multiple tissue types working together for one or more specific functions.
Card 6
Question
What is an organ system?
Answer
A group of organs and related structures that cooperate in major body functions.
Card 7
Question
What does homeostasis mean in introductory physiology?
Answer
Maintaining a relatively stable internal environment while conditions inside or outside the body change.
Card 8
Question
What is the integumentary system's main job?
Answer
It forms the body's outer barrier, limits water loss, helps regulate temperature, and provides sensation.
Card 9
Question
What are the skeletal system's main jobs?
Answer
Support and protect the body, provide levers for movement, store minerals, and house blood-forming marrow.
Card 10
Question
What is the muscular system's main job?
Answer
It produces body movement through muscle contraction and also supports posture, joint stability, and heat production.
Card 11
Question
What is the nervous system's main job?
Answer
It detects changes, integrates information, and coordinates rapid responses through sensory, processing, and motor activity.
Card 12
Question
What is the endocrine system's main job?
Answer
It uses hormones to regulate processes such as growth, metabolism, development, reproduction, and long-term homeostasis.
Card 13
Question
What is the cardiovascular system's main job?
Answer
It circulates blood to transport gases, nutrients, hormones, heat, cells, and wastes around the body.
Card 14
Question
What are the lymphatic/immune system's main jobs in this deck's combined model?
Answer
It returns excess tissue fluid to the blood, supports immune defense, and carries absorbed fats from the small intestine.
Card 15
Question
What is the respiratory system's main job?
Answer
It brings oxygen into contact with the blood and removes carbon dioxide through gas exchange.
Card 16
Question
What is the digestive system's main job?
Answer
It breaks food into absorbable components, absorbs nutrients and water, and eliminates material that was not digested.
Card 17
Question
What is the urinary system's main job?
Answer
It removes wastes in urine and regulates body-fluid volume, electrolytes, and acid-base balance.
Card 18
Question
What is the reproductive system's main job?
Answer
It produces gametes and reproductive hormones and provides structures that support fertilization and, in the female system, development before birth.
Card 19
Question
Which organ system includes the skin?
Answer
The integumentary system.
Card 20
Question
Which organ system includes bones?
Answer
The skeletal system.
Card 21
Question
In the conventional organ-system model, what structures make up the muscular system?
Answer
Primarily skeletal muscles and their associated tendons. Smooth and cardiac muscle tissue also drives movement inside other organ systems.
Card 22
Question
Which structures make up the central nervous system?
Answer
The brain and spinal cord.
Card 23
Question
How do endocrine glands release hormones?
Answer
They release hormones into the surrounding fluid and blood rather than through ducts to a surface.
Card 24
Question
What does the heart do in the cardiovascular system?
Answer
It pumps blood through the pulmonary and systemic circuits.
Card 25
Question
What is lymph?
Answer
Interstitial fluid after it enters lymphatic capillaries and begins moving through lymphatic vessels.
Card 26
Question
What route does inhaled air follow from the nose toward the gas-exchange surfaces?
Answer
Nasal cavity → pharynx → larynx → trachea → bronchi → smaller airways → alveoli.
Card 27
Question
What is the gastrointestinal tract?
Answer
A continuous muscular tube from the mouth to the anus that includes the esophagus, stomach, small intestine, and large intestine.
Card 28
Question
Which four structures form the urinary tract?
Answer
The kidneys, ureters, urinary bladder, and urethra.
Card 29
Question
What are the gonads, and what do they produce?
Answer
The ovaries and testes. They produce gametes and reproductive hormones.
Card 30
Question
Which skin layer is the outer protective barrier?
Answer
The epidermis.
Card 31
Question
What is cartilage's main role in the skeletal system?
Answer
It provides flexible support and smooth, low-friction surfaces at many joints.
Card 32
Question
What does a tendon connect?
Answer
Muscle to bone.
Card 33
Question
What structures make up the peripheral nervous system?
Answer
Nerves, ganglia, and sensory endings outside the brain and spinal cord.
Card 34
Question
What is the pituitary gland's broad endocrine role?
Answer
It releases hormones that regulate several other endocrine glands and body functions.
Card 35
Question
In what direction do arteries carry blood?
Answer
Away from the heart.
Card 36
Question
What do lymph nodes do?
Answer
They filter lymph and serve as meeting points where immune cells sample material and coordinate responses.
Card 37
Question
What are alveoli?
Answer
Tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged with the blood.
Card 38
Question
What is the esophagus's digestive role?
Answer
It transports swallowed material from the pharynx to the stomach.
Card 39
Question
What do the kidneys do?
Answer
They filter blood, remove wastes and excess substances into urine, and regulate water, electrolytes, and acid-base balance.
Card 40
Question
What do the ovaries produce?
Answer
Oocytes, commonly called egg cells, and hormones including estrogens and progesterone.
Card 41
Question
Which skin layer contains most skin blood vessels, sensory endings, hair follicles, and glands?
Answer
The dermis.
Card 42
Question
What does a ligament connect?
Answer
Bone to bone, helping stabilize a joint.
Card 43
Question
What makes skeletal muscle suited for moving the skeleton?
Answer
It contracts under voluntary control and pulls on bones through tendons.
Card 44
Question
What do sensory receptors contribute to the nervous system?
Answer
They detect changes inside or outside the body and convert them into signals the nervous system can process.
Card 45
Question
What is the thyroid gland's broad endocrine role?
Answer
It releases hormones that help regulate metabolic rate, growth, and development.
Card 46
Question
In what direction do veins carry blood?
Answer
Toward the heart.
Card 47
Question
What is the spleen's lymphatic/immune role?
Answer
It filters blood, removes aging blood cells, and supports immune responses to material carried in the bloodstream.
Card 48
Question
What is the trachea's respiratory role?
Answer
It conducts air from the larynx toward the bronchi and helps keep the airway open.
Card 49
Question
What is the stomach's main digestive role?
Answer
It stores and mixes food while beginning substantial chemical digestion of proteins.
Card 50
Question
What do the ureters do?
Answer
They carry urine from the kidneys to the urinary bladder.
Card 51
Question
What do the testes produce?
Answer
Sperm cells and hormones, especially testosterone.
Card 52
Question
How do sweat glands help regulate body temperature?
Answer
They release sweat; evaporation from the skin removes heat.
Card 53
Question
What is red bone marrow's main role?
Answer
It produces blood cells, including red blood cells, many white blood cells, and platelets.
105 cards
Human Body Systems Flashcards: 11 Organ Systems, Organs & Functions
Study this deck for freeFlashcards opens so you can start studying.
Card 54
Question
What does smooth muscle do in the walls of hollow organs and blood vessels?
Answer
Its involuntary contractions move contents through organs or adjust a vessel's diameter.
Card 55
Question
What is a neuron's basic job?
Answer
To receive, process, and transmit information using electrical and chemical signals.
Card 56
Question
What is the broad endocrine role of the parathyroid glands?
Answer
They release parathyroid hormone, a key regulator of calcium levels in the blood.
Card 57
Question
What is the main job of capillaries?
Answer
They provide thin-walled exchange sites between blood and surrounding tissues.
Card 58
Question
What is the thymus's immune role?
Answer
It is where T lymphocytes mature.
Card 59
Question
What do the bronchi do?
Answer
They carry air from the trachea into the lungs and branch into progressively smaller airways.
Card 60
Question
What is the small intestine's main digestive role?
Answer
It completes most chemical digestion and is the main site where nutrients are absorbed.
Card 61
Question
What is the urinary bladder's main role?
Answer
It stores urine until urination.
Card 62
Question
What do the uterine tubes do?
Answer
They transport an oocyte from an ovary toward the uterus and are the usual site of fertilization.
Card 63
Question
What roles do hair and hair follicles serve in the integumentary system?
Answer
They contribute to protection and sensation; follicles also help renew skin after minor injury.
Card 64
Question
How do the axial and appendicular skeletons differ?
Answer
The axial skeleton forms the body's central axis; the appendicular skeleton includes the limbs and the girdles that attach them.
Card 65
Question
Where is cardiac muscle found?
Answer
In the wall of the heart, where it contracts involuntarily to pump blood.
Card 66
Question
Why can the nervous system coordinate rapid responses?
Answer
It sends fast electrical signals along neurons and uses chemical signals across synapses.
Card 67
Question
What is the broad endocrine role of the adrenal glands?
Answer
They release hormones involved in stress responses, metabolism, salt balance, and blood-pressure regulation.
Card 68
Question
Why is blood considered part of the cardiovascular system?
Answer
It is the circulating transport tissue moved through the heart and blood vessels.
Card 69
Question
What immune role do the tonsils serve?
Answer
They sample material entering through the mouth and nose and help start immune responses.
Card 70
Question
How does the diaphragm support the respiratory system?
Answer
Its contraction enlarges the thoracic cavity, drawing air into the lungs. It is skeletal muscle working in ventilation.
Card 71
Question
What is the large intestine's main digestive role?
Answer
It absorbs water and electrolytes and compacts the remaining material into feces.
Card 72
Question
What does the urethra do?
Answer
It carries urine from the bladder to the outside of the body.
Card 73
Question
What is the uterus's main reproductive role?
Answer
It receives an implanted embryo and supports development before birth.
Card 74
Question
What do nails contribute to the integumentary system?
Answer
They protect the tips of fingers and toes and provide a firm counter-surface for fine grasping.
Card 75
Question
Which skeletal structures protect the brain, spinal cord, heart, and lungs?
Answer
The skull protects the brain, vertebrae protect the spinal cord, and the rib cage helps protect the heart and lungs.
Card 76
Question
How does skeletal muscle contribute to posture and body temperature?
Answer
Ongoing small contractions stabilize posture, while muscle activity releases heat.
Card 77
Question
How do the central and peripheral nervous systems differ?
Answer
The central nervous system is the brain and spinal cord; the peripheral system connects them with the rest of the body.
Card 78
Question
What do the pancreatic islets contribute to the endocrine system?
Answer
They release hormones, including insulin and glucagon, that help regulate blood glucose.
Card 79
Question
How do pulmonary and systemic circulation differ?
Answer
Pulmonary circulation moves blood between the heart and lungs; systemic circulation moves it between the heart and the rest of the body.
Card 80
Question
What do intestinal lacteals absorb?
Answer
Dietary fats and fat-soluble vitamins from the small intestine into the lymphatic circulation.
Card 81
Question
What is external respiration?
Answer
The exchange of oxygen and carbon dioxide between air in the lungs and blood in pulmonary capillaries.
Card 82
Question
Which major accessory organs add secretions to the digestive tract?
Answer
The salivary glands, liver, gallbladder, and pancreas.
Card 83
Question
How do the kidneys help keep body fluids stable?
Answer
They adjust how much water, electrolytes, acids, and bases leave the body in urine.
Card 84
Question
What is the epididymis's reproductive role?
Answer
It is the coiled duct where sperm mature and are stored before entering the ductus deferens.
Card 85
Question
Which organ system includes hair, nails, sweat glands, and oil glands?
Answer
The integumentary system.
Card 86
Question
Which organ system stores most of the body's calcium?
Answer
The skeletal system, mainly in the mineral matrix of bone.
Card 87
Question
Which organ system produces most visible body movement through contraction?
Answer
The muscular system, working with the skeleton and nervous system.
Card 88
Question
Which organ system coordinates rapid sensory and motor responses?
Answer
The nervous system.
Card 89
Question
Which organs have both reproductive and endocrine roles?
Answer
The ovaries and testes: they produce gametes for the reproductive system and hormones for endocrine signaling.
Card 90
Question
Which organ system consists of the heart, blood, and a closed network of vessels?
Answer
The cardiovascular system.
Card 91
Question
Which organ system returns excess interstitial fluid to the blood and includes lymph nodes?
Answer
The lymphatic/immune system.
Card 92
Question
Which organ system removes carbon dioxide and thereby helps regulate blood pH?
Answer
The respiratory system.
Card 93
Question
Why are the liver, gallbladder, and pancreas called accessory digestive organs?
Answer
Food does not pass through them, but their secretions support digestion in the gastrointestinal tract.
Card 94
Question
Which urinary organ stores urine before it leaves the body?
Answer
The urinary bladder.
Card 95
Question
Which reproductive organ supports an implanted embryo and fetal development?
Answer
The uterus.
Card 96
Question
How do the skeletal and muscular systems work together to produce movement?
Answer
Skeletal muscles contract and pull on bones, which act as levers across joints.
Card 97
Question
How do the respiratory and cardiovascular systems cooperate in gas transport?
Answer
The respiratory system exchanges gases in the lungs; the cardiovascular system carries oxygen to tissues and returns carbon dioxide to the lungs.
Card 98
Question
How do the nervous and endocrine systems differ in body control?
Answer
The nervous system usually sends fast, targeted signals; the endocrine system sends hormones through the blood for generally slower, longer-lasting effects.
Card 99
Question
How do the digestive and lymphatic systems cooperate in fat absorption?
Answer
Lacteals in small-intestinal villi absorb dietary fats and carry them into the lymphatic circulation.
Card 100
Question
How do the integumentary and muscular systems help regulate body temperature?
Answer
Skin promotes heat loss through sweating and blood-flow changes, while muscle contraction produces heat.
Card 101
Question
How does the urinary system support cardiovascular homeostasis?
Answer
By adjusting water and electrolyte excretion, the kidneys help regulate blood volume, composition, and pressure.
Card 102
Question
How do the endocrine and reproductive systems cooperate?
Answer
Hormones regulate reproductive development and function, while the gonads produce both gametes and hormones.
Card 103
Question
How do the skeletal and lymphatic/immune systems connect through bone marrow?
Answer
Red bone marrow produces blood cells, including white blood cells that take part in immune defense.
Card 104
Question
How do the integumentary and nervous systems cooperate in sensation?
Answer
Receptors in the skin detect touch, temperature, pressure, and potentially harmful stimuli, then sensory nerves carry those signals toward the central nervous system.
Card 105
Question
How do the muscular and digestive systems cooperate to move food?
Answer
Smooth muscle in the digestive tract produces coordinated contractions that propel and mix its contents.
105 cards
Human Body Systems Flashcards: 11 Organ Systems, Organs & Functions
Flashcards opens so you can start studying.