Human Anatomy Flashcards

What are the two major functional divisions of the respiratory system?

🎓 Conducting zone and respiratory zone
💬 Conducting zone moves air; respiratory zone does gas exchange

What structures are part of the conducting zone?

🎓 Nose, pharynx, larynx, trachea
💬 The air passageways before gas exchange

What structures belong to the respiratory zone?

🎓 Pleural cavity, lungs, alveoli
💬 These areas actually allow oxygen and CO₂ to swap

What are the functions of the conducting zone?

🎓 Conduction of air; filtration, warming, humidifying air; olfaction
💬 Prepares air for the lungs and helps you smell

What tissues and openings make up the external nose?

🎓 Fibrofatty tissue and external nares
💬 Soft tissue + nostrils = air intake

What structures contribute to the nasal septum?

🎓 Ethmoid bone and septal cartilage
💬 Separates left and right nasal cavities

What bones form the nasal conchae?

🎓 Superior & middle from ethmoid; inferior is its own bone
💬 They swirl and condition incoming air

What are nasal meatuses and where are they located?

🎓 Chambers located below each nasal concha
💬 Pathways under the swirl bones for airflow

What are the three anatomical divisions of the pharynx?

🎓 Nasopharynx, oropharynx, and laryngopharynx
💬 Upper (air), middle (air + food), lower (air + food)

What is the role of the nasopharynx in respiration?

🎓 Serves as a passageway for air
💬 Carries air from nose to throat

What is the pharyngeal tonsil in the nasopharynx and what is its function?

🎓It is Aggregated Lymphoid tissue that destroys inhaled pathogens with immune cells
💬 Helps fight airborne germs (shrinks in adults)

What structure connects the inner ear to the pharynx, and what is its function?

🎓 Eustachian tubes connect the inner ear cavity to the pharynx
💬 They equalize pressure between the ear and throat

What is the function of the uvula during swallowing?

🎓 Closes off the nasopharynx during swallowing
💬 Prevents food or liquid from going up into the nose

What is the function of the oropharynx?

🎓 Passageway for both air and food
💬 Middle throat that shares breathing and eating roles

What is the fauces?

🎓 The opening to the oral cavity into the oropharynx
💬 The gateway between the mouth and throat

What tonsils are found in the oropharynx and what do they do?

🎓 Palatine and lingual tonsils: aggregated lymphoid tissue that destroys inhaled/ingested pathogens with immune cells
💬 Immune tissue that guards what you breathe or swallow

What is the function of the laryngopharynx?

🎓 Passageway for air and food
💬 Directs air to the larynx and food to the esophagus

What is the role of the larynx?

🎓 Protects the airway during swallowing and is involved in sound production
💬 Keeps food out of lungs and helps make your voice

How many cartilages make up the larynx and how are they grouped?

🎓 9 total: 3 unpaired (thyroid, epiglottis, cricoid), 3 pairs (arytenoid, corniculate, cuneiform)
💬 3 big solo parts + 3 little matching pairs

What is the function of the thyroid cartilage and what feature is it known for?

🎓 Forms the anterior larynx; has the laryngeal prominence (“Adam’s apple”), which is more prominent in biological males due to testosterone and a sharper angle between left and right sides
💬 It makes the “Adam’s apple” — sharper angle = deeper voice (more common in males)

What is the role of the epiglottis?

🎓 Closes the glottis during swallowing
💬 Blocks the airway to stop choking

Where is the cricoid cartilage located and what is its shape?

🎓 Inferior to thyroid cartilage; forms a complete ring at the top of the trachea
💬 Ring base of the voice box; connects to windpipe

What are the three unpaired cartilages of the larynx and their roles?

🎓 Thyroid (anterior), epiglottis (superior – closes glottis when swallowing), cricoid (inferior – ring at trachea opening)
💬 Shield (thyroid), flap (epiglottis), ring (cricoid)

What are the three paired cartilages of the larynx and their role?

🎓 Arytenoid, corniculate, and cuneiform; they contribute to sound production
💬 These move the vocal cords so you can talk

What makes up the glottis?

🎓 True vocal cords + vestibular folds (false vocal cords) + the space between them
💬 Real vocal cords (white folds), backup folds (false), and the air gap

What is the difference between true and false vocal folds?

🎓 True vocal cords: white, membranous, connected to muscles; false cords: mucous membrane folds
💬 True cords make sound; false cords don’t

What causes differences in voice between individuals?

🎓 Differences in vocal cord size (larger cords = deeper voice)
💬 Bigger cords = deeper sound

What are the tracheal cartilages made of and how are they arranged?

🎓 16–20 C-shaped rings of hyaline cartilage connected by dense connective tissue; trachealis muscle closes off the back
💬 Stiff rings in front, muscle band in back

What is the function of the trachealis muscle?

🎓 Closes the posterior side of the trachea and allows flexibility
💬 Lets you swallow without choking on your trachea

What are the branches of the bronchial tree from largest to smallest?

🎓 Primary → Secondary → Segmental bronchi → Bronchioles
💬 Big → medium → small tubes → tiny tubes

What are bronchioles and what makes them different from bronchi?

🎓 Bronchioles are the smallest airways at less than 1mm wide, do some gas exchange, and lack cartilage
💬 Tiny airways with no rings

What is the carina and what is its function?

🎓 The point where the trachea splits into bronchi; has nerve tissue that triggers coughing
💬 Split point of the windpipe — cough sensor lives here

What is the main function of the respiratory zone?

🎓 Gas exchange
💬 Where oxygen and carbon dioxide swap

How do the lungs differ between the right and left sides?

🎓 Right: shorter, wider, 3 lobes; Left: smaller, 2 lobes, cardiac notch
💬 Right = 3 lobes, shorter = liver is under it, wider = doesn’t have a cardiac notch
Left = 2 lobes + heart dent, holds less air = because of cardiac notch

What is the pleural cavity and what does it contain?

🎓 The pleural cavity is a thin fluid filled space between the visceral and parietal pleura, that contains the lungs
💬 Space around the lungs filled with slippery fluid

What is the pleura and what are its two layers?

🎓 A serous membrane with visceral pleura (on lung) and parietal pleura (lining cavity)
💬 Lung wrapper: inner = lung, outer = rib ca

What secretes the pleural fluid and what is it’s function?

🎓 Secreted by mesothelium to reduce friction
💬 Slippery lube for smooth breathing

What are terminal bronchioles and respiratory bronchioles?

🎓 Terminal: last conducting branch; Respiratory: start of gas exchange
💬 Terminal = end of air tunnel; Respiratory = start of gas swap

What are alveoli and what is their structure?

🎓 Tiny sacs made of simple squamous epithelium; main site of gas exchange
💬 Thin-walled air sacs where oxygen enters blood

What makes up the respiratory membrane?

🎓 Alveolar membrane + capillary membrane = respiratory membrane
💬 Air sac wall + blood vessel wall = gas swap barrier

How do gases move across the respiratory membrane?

🎓 Gases move by simple diffusion across the respiratory membrane
💬 Oxygen and CO₂ slide through the walls without help

What are the organs of the alimentary canal?

🎓 Mouth, esophagus, stomach, intestines
💬 The main food tube from start to finish

What are the accessory digestive organs?

🎓 Liver, pancreas, gall bladder
💬 Organs that help digest food by adding enzymes or bile

What are the five main functions of the digestive system?

🎓 Ingestion, digestion (mechanical & chemical), absorption, transportation, defecation
💬 Eat, break down, absorb, move, and eliminate food

How is the digestive system divided?

🎓 Divided by function and development into:

• Alimentary canal: forms the gastrointestinal tract

• Accessory organs: help break down food
  💬 Main tube vs. helper organs

What organs make up the gastrointestinal (GI) tract?

🎓 Mouth, esophagus, stomach, small intestine, large intestine
💬 The organs food physically travels through

How long is the alimentary canal?

🎓 Approximately 25 feet during life
💬 It’s like a 25-foot-long food tunnel

What separates the inside and outside of the body in digestion?

🎓 The interior surface is the true body interior; nutrients must cross the exterior surface (the GI tract lining) to enter the body
💬 Your gut is technically outside your body until nutrients are absorbed in

What are the three main layers of the alimentary canal?

🎓 Mucosa (inner), submucosa (middle), muscularis (outer)
💬 Inner lining, support tissue, and muscle layer

What is the epithelium of the mucosa and its function?

🎓 Inner part of mucosa in direct contact with food; contains goblet cells that secrete mucus; has a short lifespan and rapid turnover
💬 It touches food, makes mucus, and replaces itself quickly

What is the lamina propria and its role?

🎓 Middle sub-layer of mucosa made of loose connective tissue; contains blood and lymph vessels, and lymphocyte clusters for immune support
💬 It holds the plumbing and immune cells

What is the muscularis mucosae and what does it do?

🎓 Outermost layer of the mucosa; thin smooth muscle layer that causes folding in the stomach and small intestine
💬 It helps fold the lining to increase surface area

What is the mucosa?

🎓 The innermost layer of the alimentary canal, consisting of epithelium, lamina propria, and muscularis mucosae
💬 It’s the inside lining that touches food, absorbs nutrients, and makes mucus

What is the submucosa?

🎓 A middle layer of dense connective tissue containing blood vessels, lymph vessels, nerves, and glands
💬 It connects and supports the layers above and below, and carries vessels and nerves

What is the muscularis?

🎓 The outer layer of the GI tract wall, made of smooth muscle (except for skeletal in parts of the esophagus), responsible for mechanical digestion and propulsion
💬 Muscle layer that crushes and moves food along the tract

What is the submucosa layer made of?

🎓 Dense connective tissue
💬 Tough support tissue under the lining

What is the function of the submucosa?

🎓 Binds the mucosa to the muscularis layer
💬 It connects the inner lining to the muscle layer

What structures are found in the submucosa?

🎓 Blood vessels, lymph vessels, submucosal nerve plexus, and digestive glands
💬 It carries blood, lymph, nerves, and glands

What type of muscle is found in the muscularis layer?

🎓 Typically two layers of smooth muscle: circular (inner) and longitudinal (outer)
💬 Two muscle layers that squeeze and push food

How is the muscularis layer modified in the esophagus?

🎓 It contains skeletal muscle instead of smooth muscle
💬 Top part uses voluntary muscle to start swallowing

What muscle modification is found in the stomach?

🎓 It has a third muscle layer: the oblique layer
💬 Extra layer for stronger churning

What is different about the muscularis layer in the large intestine?

🎓 Longitudinal muscle is organized into bands
💬 Outer muscle is bundled into strips

What are the main functions of the muscularis layer?

🎓 Mechanical digestion, mixing/churning food for chemical digestion, and propelling food forward
💬 It crushes and moves the food along

What is the peritoneum?

🎓 A serous membrane made of squamous epithelium and connective tissue that secretes serous fluid
💬 A slippery lining for your abdominal cavity

What are the two layers of the peritoneum?

🎓 Visceral peritoneum (lines organs) and parietal peritoneum (lines the body wall)
💬 Inner layer touches organs; outer layer touches the wall

What do folds of the peritoneum contain?

🎓 Abdominal organs (e.g., stomach and intestines), blood vessels, lymph vessels, and nerves
💬 They hold organs and carry pipes and wires (vessels & nerves)

What are the six major activities of the digestive system?

🎓 Ingestion, propulsion, mechanical digestion, chemical digestion, absorption, defecation
💬 Eat, move, crush, dissolve, absorb, eliminate

What is ingestion?

🎓 The entry of food into the alimentary canal
💬 Putting food in your mouth

What is propulsion and what types are involved?

🎓 Movement of food through the canal:

• Voluntary: swallowing

• Involuntary: peristalsis (smooth muscle waves)
  💬 Swallowing + squeezing waves that push food down

What is mechanical digestion and what are two examples?

🎓 Mechanical digestion breaks food into smaller pieces to aid chemical digestion.

• Mastication (chewing)

• Segmentation (localized contractions in small intestine to mix/subdivide food)
  💬 Physically breaking food down by chewing and mixing

What is chemical digestion?

🎓 The process where digestive secretions break complex molecules into smaller chemical building blocks
💬 Using enzymes to break food into basic parts like sugars and amino acids

What is absorption in digestion?

🎓 The movement of nutrients from the GI tract into the body (blood or lymph)
💬 When nutrients get pulled into your body from the gut

What is defecation?

🎓 The elimination of undigested material from the alimentary canal
💬 Getting rid of waste through the rectum

What are the labia and their features?

🎓 The lips — outer covering transitions to mucous membrane inside the mouth; thin keratin layer and highly vascular, giving a red color
💬 Lips are red because they’re thin and full of blood vessels

What is the oral cavity and what does it include?

🎓 Also called the buccal cavity, it includes the space inside the mouth, bordered by the lips, cheeks, palate, and tongue
💬 The inside of your mouth where food first enters and chewing starts

Why are lips so sensitive?

🎓 A large portion of the cerebral cortex is dedicated to processing input from them
💬 The brain gives lips high-touch sensitivity

What makes up the palate and what are its parts?

🎓 The palate separates the oral and nasal cavities:

• Hard palate = bone

• Soft palate = mostly skeletal muscle
  💬 Roof of mouth: front part is hard, back part is soft and movable

What are the functions of the tongue?

🎓 Ingestion, mechanical and chemical digestion, sensation, swallowing, and vocalization
💬 The tongue helps with eating, tasting, swallowing, and talking

What divides the tongue into left and right halves?

🎓 A medial septum
💬 Line down the middle that splits it evenly

What is the lingual frenulum?

🎓 A ligament that attaches the tongue to the floor of the mouth
💬 The string under your tongue

What are the major functions of saliva?

🎓 Moistens mouth/teeth, lubricates food, begins chemical digestion (via salivary amylase), and has antimicrobial activity
💬 Saliva softens food, starts breaking down carbs, and kills germs

What is saliva mostly made of?

🎓 ~99% water, plus ions, enzymes, and waste products
💬 Almost entirely water with some helpful extras

What are the three major salivary glands and their ducts?

🎓

• Submandibular glands (floor of mouth → submandibular ducts)

• Sublingual glands (under tongue → lesser sublingual ducts)

• Parotid glands (near ears → parotid ducts by upper molars)
  
  💬 Three sets of glands that release saliva through different ducts

What is the function of teeth in digestion?

🎓 Teeth are used for mechanical digestion
💬 They break food into smaller pieces by chewing

What are the two main parts of a tooth?

🎓

• Crown: above the gumline

• Root: embedded in alveolar processes of maxilla/mandible
  💬 Top = crown (visible); bottom = root (inside jaw)

What structure inside the both the Crown and Root contains connective tissue, blood vessels, and nerves?

🎓 Pulp cavity
💬 The soft tissue center that keeps the tooth alive

What is the root canal?

🎓 The portion of the pulp cavity that extends into the root
💬 The tunnel in the root holding nerves and vessels

What hard tissue forms the bulk of the tooth beneath the enamel and cementum?

🎓 Dentin
💬 The strong, bone-like material under the surface layers

What is cementum?

🎓 A very hard tissue that covers the root of the tooth
💬 Protective coating on the tooth’s root

What is enamel?

🎓 The hardest substance in the body; covers the crown
💬 Super tough outer shell of the visible tooth

What causes cavities and tooth decay?

🎓 Cavities are caused by acid released by colonies of sugar-eating bacteria. The acid chemically erodes the enamel, leading to holes (cavities) in the teeth.
💬 Bacteria eat sugars → make acid → acid dissolves enamel → hole forms (cavity)

What is plaque?

🎓 A sticky, colorless film made by and containing bacteria
💬 Bacterial layer that sticks to teeth and causes decay

What are incisors and their function?

🎓 8 total (4 top, 4 bottom); sharp-edged teeth used for cutting and biting
💬 Front teeth that slice food

What are cuspids (canines) and their function?

🎓 4 total (2 top, 2 bottom); pointed teeth used for tearing and piercing
💬 Fang-like teeth for ripping food

What are premolars (bicuspids) and their function?

🎓 8 total (4 top, 4 bottom); flat and rounded for chewing
💬 Between canines and molars — grind and crush

What are molars and their function?

🎓 12 total (6 top, 6 bottom); multi-cusped and used for chewing
💬 Big back teeth that mash food

What are wisdom teeth and when do they erupt?

🎓 The last molars to erupt, usually in early adulthood
💬 Extra chewing teeth from when jaws were larger

How many deciduous (baby) teeth do humans have and when do they appear?

🎓 20 teeth; appear around 6 months, replaced between 6–12 years
💬 You get 20 baby teeth that fall out in childhood

How are deciduous teeth distributed by type?

🎓 8 incisors, 4 cuspids, 0 premolars, 8 molars
💬 Baby teeth don’t have premolars

How many permanent teeth do adults have and what types?

🎓 32 teeth: 8 incisors, 4 cuspids, 8 premolars, 12 molars
💬 32 total adult teeth, with all 4 types present