BIOL 205 EXAM 4

redlining

• form of institutional racism

• Great Depression (1920s) → FDR’s New Deal aimed to get poorer/ disadvantaged Americans homes

• National Housing Act (1934) → low-interest loans

  • banks decided who got home loans (usually wealthy/white)

    • home ownership/loans often denied to families of color

• four colors determining who lived where

  • green (business), blue (suburbs/white collar families), yellow (declining area/working class), red (hazardous areas, low-class white families, black/brown people)

• Alta Dena → not as redlined (generational wealth, high black ownership)

environmental racism

• fracking: type of drilling extracting oil/natural gases w/ high pressure water

• minority groups disproportionately burdened with environmental hazards (e.g. toxic waste, garbage dumps, water/air pollution, etc.)

  • NAACP → 39% of people living near coal plants are POC

  • cancer/illness rates higher in polluted areas

• factories/power plants/freeways near low-income communities of color

• more COVID deaths (3x higher death rates) and other sicknesses

  • higher asthma rates, lead poisoning, lung cancer, etc.

• Wilmington, CA (13 mi from campus) → highly centralized industrialization

  • 89% of families are POC according to U.S. Census

respiratory system (primary function and location)

• respiratory system

  • primary function → exchange of gases (b/c of cellular respiration)

  • location → upper (face/neck) vs. lower (chest cavity)

what is included in the upper respiratory tract?

• nasal cavity

• pharynx

• larynx

nasal cavity

• nares (nostrils) with hair and septum

• mucus and four sinuses

  • maxillary (cheeks), frontal (forehead), ethmoid (between eyes), sphenoid (behind eyes)

• nasolacrimal duct and Eustachian tube

• cilia keep beating after death

what is included in the pharynx (throat)?

• food/air tubes

• tonsils

• three subparts → nasopharynx (nose), oropharynx (mouth), laryngopharynx (larynx)

• larynx

how does a sore throat happen?

mucosal folds get swollen and don’t flap

what is included in the lower respiratory tract?

• trachea

• bronchial tree

• lungs

trachea (“windpipe”)

• c-shaped cartilaginous rings anterior to esophagus

  • coughing → smooth muscle contracts and causes trachea to narrow (ex. thumb over water hose)

bronchial tree

• R/L 1° bronchus → 2°/3° bronchi (trachea splits) → bronchioles

  • thinner walls

  • less cartilage

  • more smooth muscle

lungs

• three lobes on right lung (RT); two lobes on left lung (LT)

• pleura: thin layer of tissue covering lungs/lining interior wall of chest cavity

• COVERED in capillaries (network); allows gas exchange

surfactant

• decreases surface tension made by lungs

  • keeps alveoli (air sacs at ends of bronchioles) from collapsing

• reduces cohesion of water (prevents hydrogen bonding)

  • premature children don’t have surfactants yet

breathing

• inspiration (inhalation)

• expiration (exhalation)

inspiration vs. expiration

• inspiration (inhalation)

  • active work

  • diaphragm contracts/flattens

  • lowers thoracic pressure → forces us to inhale (air rushes in)

  • NO SUCKING; uses ATP instead

• expiration (exhalation)

  • thorax contracts → ribs down/in (elastic recoil)

  • diaphragm relaxes/rises (surfactant)

  • NO ATP

forced inhalation/exhalation

• uses muscles of back/neck/chest

• reason why coughing/laughing hurts

volume vs. capacity

• volume: actual measurement

• capacity: adding volumes together

tidal volume (TV)

• volume of air inhaled/exhaled while breathing normally or at rest

  • *you can’t breathe out all air!

inspiratory reserve volume (IRV) vs. expiratory reserve volume (ERV)

• IRV: extra air you can inhale while breathing normally or at rest

• ERV: extra air you can exhale while breathing normally or at rest

vital capacity (VC)

maximum amount of air you can exhale after maximum inhalation

calculating vital capacity

vital capacity (VC) = expiratory reserve volume (ERV) + tidal volume (TV) + inspiratory reserve volume (IRV)

residual volume (RV)

air remaining in lungs after maximum/forceful expiration (~1-1.5 liters)

total lung capacity (TLC)

maximum volume of air lungs can hold after a full/deep breath (~6 liters)

calculating total lung capacity

total lung capacity (TLC) = vital capacity (VC) + residual volume (RV)

internal respiration/gas exchange vs. external respiration/gas exchange

• internal respiration happens in tissues

  • blood capillaries w/ tissue cells

  • diffusion (O₂ exits blood and CO₂ enters blood)

  • O₂ w/ out hemoglobin = deoxyhemoglobin (dark red blood)

• external respiration happens in lungs

  • air in alveoli w/ blood in capillaries

  • diffusion (O₂ enters blood and CO₂ exits blood)

  • O₂ + hemoglobin = oxyhemoglobin (bright red blood)

relationship between O₂ and CO₂ in lungs/tissue

• O₂ in air inhaled > tissue in lungs

• CO₂ in tissue > oxygen in environment

chemical control

• chemoreceptors (medulla, carotid bodies, aortic bodies)

• low (regulated) pH increases rate/depth of breathing

  • CO₂ + H₂O → carbonic acid → H+ and bircarbonate

control of ventilation

• normally unconscious/automatic

  • ex. yawning, burping, hiccups, sneezing

• can be overridden

lung cancer

• cancer starting in lungs

• coughing (blood), weight loss, shortness of breath, chest pains

• 85% due to smoking + ~5% second hand

  • other ~10% from pollutions/genetics/fires

• not dying from lung cancer itself

  • cilia lost → secretions become infected = pneumonia or lung abscess

• metastasis (cancer from primary tumor has spread to other sites)

pneumonia

• viral/bacterial infection of lungs

  • bronchi and alveoli fill w/ thick fluid/inflammatory cells

• high fever, chills, headache, chest pain

• RFs: cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), asthma, diabetes, heart failure, smoking, flu, etc.

• may be opportunistic if immunocompromised

  • disease caused by bacteria not usually harmful in healthy individuals but more severe for those with weakened immune systems

• medication for symptoms, antibiotic of bacterial, etc.

cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD)

• CF: inability to make cilia (which cannot clear bacteria/debris from airways)

• COPD: lung disease restricting airflow (usually caused by smoking)

asthma

• long-term inflammatory disease of airways in lungs

• bronchi and bronchioles affected

  • genetic (autoimmune/persistent) and environmental (triggered)

• wheezing, shortness of breath, sometimes cough w/ mucus production

• not curable, but treatable

bronchitis

• inflammation of bronchi

• coughing up mucus, wheezing, shortness of breath, chest discomfort

• chronic vs. acute (chest cold)

  • usually caused by smoking or virus

  • chronic obstructive pulmonary disease (COPD)

laryngitis

• inflammation of larynx

• hoarseness or loss of voice

  • less common → sore throat, difficulty swallowing, etc.

• infectious (URI) vs. non-infectious (yelling)

  • URI = upper respiratory infection

• rest to recover!

rhinovirus

• “common cold”

• sore throat, runny/congested nose, sneezing/cough, muscle aches, fatigue, malaise, headache, etc. (NO FEVER)

• seasonal (happens in fall/winter)

  • thrives in 89° F (coldest parts of body → hands/feet/ears)

• mouth and nose → symptoms within ~20 hrs

  • lytic (kills host cell)

influenza

• “the flu”

• fever (aches/pains), runny nose, sore throat, muscle pains, headache, coughing, tiredness

  • bedridden for a few days

  • fluid and bleeding

• can get it from pigs/horses/birds

• mouth and nose → ~2 day incubation period

• seasonal vaccine b/c virus evolves so quickly (lytic)

what are the main differences between the cold and the flu?

• fever present in flu but not cold

  • generally more severe symptoms

gastrointestinal (GI) tract

• extends from mouth to anus (~20 ft of intestines)

• also called alimentary canal

• lumen: “hole”

  • ex. GI tract = stack of donuts, lumen = hole in donut

cell division

• fertilized egg undergoes mitosis and becomes a zygote (1+ cell)

• multiplies until it becomes a ball of cells (morula)

  • blastula (hollow ball of cells)

protosome vs. deuterostome

• protosome: organism’s mouth made first (anus made second)

• deuterostome: organism’s mouth made second (anus made first)

primary function of digestive system

• process food → macros

  • humans can’t make their own food

food processing

• ingestion (food intake)

• digestion → chemical (enzymes) and mechanical (teeth/tongue)

• absorption

• elimination

digestive tract

• four (muscular) layers

• digestive system (smooth) muscles move slow/controlled

  • longitudinal and circular layers of SM help move food around

primary function of mouth

mechanical/chemical digestion

bolus

chewed food mixed w/ saliva

accessory organs of digestive system

• teeth → 20 deciduous (baby) teeth and 32 adult teeth

• three salivary glands

  • parotid SG, sublingual SG, submandibular SG

  • amylase: enzyme in saliva cutting starch into sugars

• tongue: food manipulator

  • sense of taste/smell interconnected (food particles enter nasal cavity)

    • hard palate (behind upper teeth)

    • soft palate (back of mouth)

    • uvula: connective tissue assisting in swallowing/speech

swallowing

• act of passing something from mouth to pharynx into esophagus

  • voluntary for normal/working nervous system

peristalsis

• rhythmic contracting/relaxing of GI tract muscle

  • moves food (involuntary)

    • pharynx protected by epiglottis

    • esophagus protected by sphincters

      • ~7 seconds for bolus to pass down esophagus

epiglottis

protective cartilaginous flap preventing food from entering airways

sphincter

muscle controlling flow of substances (food/waste/bile/blood) through body

stomach

• “j” shaped pouch

• three extra muscular (oblique) layers

  • churns food/acids/digestive juices

• controlled slow emptying (1 tsp at a time)

  • empties in ~2-6 hours

chyme

• food + stomach acid

primary function of stomach

chemical/mechanical digestion

secondary function of stomach

food storage and protein digestion

tertiary function of stomach

• absorption (emergency response)

  • some H₂O and medicine

  • alcohol/caffeine can pass (stomach soluble)