Human Biology Exam #2

4.5-5.5 (acidic)

Skin pH

10-15%

Skin → percentage of total body mass

Skin

Largest organ of body

Every 28 days

How often are skin cells completely renewed?

Eyelids

Location of thinnest skin layer

Protection (mechanical trauma, pathogens, environment), sensation, thermoregulation, excretion (sweat), vitamin D

Functions of skin

Epidermis and dermis

Two layers of skin

Hypodermis

Layer of fat below skin (not technically a skin layer)

Stratum corneum → s. lucidum → s. granulosum → s. spinosum → s. basali (boy scouts grow lots-a corn)

Layers of epidermis

Blood vessels, sensory receptors (tactile and lamellated), dermal papillae (create fingerprints)

Parts of dermis

Differences in layers between thick/thin skin

Primary in skin pigmentation, protects cellular DNA, decreases vitamin D synthesis

Role of melanin

Carotene, hemoglobin

Secondary in skin pigmentation

Erythema

Influx of blood flow to superficial skin, turns red

Paylor

Decreased blood flow in skin, turns white

Cyanosis

Decreased oxygen in skin, turns blue

Jaundice

Elevated bilirubin in skin caused by liver damage breaking down blood cells, turns yellow

Parabens, talc, triclosan

Ingredients in make-up

Oxybenzone (hormone disruption), octinoxate (poisonous to marine life), octocrylene (absorbs into body)

Ingredients in sunscreen

Eccrine

Sweat glands that excrete sweat onto skin surface; the majority

Apocrine

Sweat glands that excrete via hair follicles

Cerumin (earwax)

Substance released by ceruminous gland

Sebaceous gland

Type of gland that releases oil

First degree burn

Sunburn

Second degree burn

Burn causing blisters

Third degree burn

Burn into hypodermis, tissue damage

18%

% burned on front of torso

18%

% burned on front and back of one leg

4.5%

% burned on back of one arm

4.5%

% burned on face

Botulism

A type of bacterium called Clostridium botulinum produces a toxin that attacks the nervous system; via food (honey), wound, in infants, or from Botox

Trouble swallowing, speaking, weakness in facial muscles, change in vision, difficulty breathing, paralysis

Symptoms of botulism

Natural immune defense, induced vomiting, antibiotics (wound only)

Treatment for botulism

Necrotizing fasciitis (flesh eating bacteria)

Severe bacterial infection in the tissue under skin (fascia) causing aches, fevers, chills, nausea, severe pain at infection site; also discoloration, swelling, worsening pain/fever, blisters

Necrotizing fasciitis

Infection with high prevalence for people with diabetes or weakened immune systems

Skin and mucous membranes that act as barriers to entry

First line of immune defense

Innate immunity (born with it)

Second line of immune defense

Adaptive immunity (individual, depends on what you’re exposed to)

Third line of immune defense

Lymphatic

The second and third lines of immune defense work with which other system?

Residence for immune cells (B cells, T cells, macrophages), trap pathogens for immune system with little “nets”, activate immune cells

Role of lymph organs

Responds to all pathogens in same way, quick response time (first 12 hours after exposure), phagocytes and NK cells

Explain innate/nonspecific immunity.

Phagocytes

Type of innate immunity that eats foreign and damaged cells

NK cells

Type of lymphocyte that detects abnormalities and destroys them

Redness (rubor), heat (calor), swelling (tumor), pain (dolor), loss of function

5 signs of inflammation

Respond to antigens, cell-mediated (T and B cells), has “memory”, must be exposed to specific antigen to develop this immunity; foundation of vaccines

Explain adaptive immunity.

T cells

Adaptive immune system cells that directly attack antigens

B cells

Adaptive immune system cells that are antibody-mediated

Live, attenuated

Vaccine that is a “weakened” version of the pathogen

Inactivated

Vaccine that has “dead” pathogen and requires boosters

Subunit

Vaccines that utilizes part of pathogen and requires boosters

mRNA

Vaccine that has strand of pathogen mRNA for cell absorption, which is then found to be “foreign”

Viral infection; spreads via bite or scratch; most common in bats, raccoons, skunks, and foxes; initially presents flu-like symptoms but within 2 weeks, anxiety, confusion, aggression, excess saliva, hallucinations; 3-10 days fatal post symptoms; body cannot fight on its own

Explain rabies.

Ingestion, secretion, propulsion, digestion, absorption, defecation

Functions of digestive system

Peristalsis

Circular propulsive motion of smooth muscle from top to bottom

Oral cavity → pharynx → esophagus → stomach → small intestine → large intestine

Path through digestive system

Mechanical breakdown of food, chemical breakdown of carbs

Function of oral cavity in digestive system

Propulsion to esophagus, location of epiglottis; voluntary and involuntary swallowing

Function of pharynx in digestive system

Contains gastric glands which secrete “gastric juice” (pH 1.5-3.5), smooth muscle contractions of mixing of food and acids

Function of stomach in digestive system

Duodenum, jejunum, and ileum

Sections of small intestine

Ileocecal valve

Prevents backflow from large intestine

Duodenum

Receives secretions from pancreas and gallbladder

Jejunum

Most active site in small intestine for chemical digestion and absorption

500

How many types of bacteria exist in the large intestine/colon?

Waste removal, maintain fluid and electrolyte balance, acid-base balance, and blood pressure, regulation of erythropoiesis (red blood cell production)

Function of the kidneys

Defined BMI > 30, chronic disease according to CDC

Obesity

High blood pressure, joint dysfunction/osteoarthritis, sleep apnea, diabetes, fatty liver, intertrigo (skin fold infections)

Effects of obesity

41%

Percentage of obesity in college students as of 2021

Excess calorie intake, usually caused by stress, social situations, BP meds, birth control

Causes of obesity

Malignant

An uncontained tumor

Benign

A contained tumor

Grow in the absence of signals for mitosis, ignore cease signals (refuse apoptosis), invade surroundings (normal cells stop), demand blood supply, develop mutations in chromosomes, numerous energy sources → rapid growth

Cancer cells (as compared to normal cells)

Carcinoma, affects epithelial cells (covers internal and external body surfaces)

Most common type of cancer and what it affects

Bone and soft tissue (muscle, fat, blood vessels, lymph vessels, tendons, ligaments)

Where do sarcomas form?

Create too many white blood cells, which crowd out normal blood cells → make it difficult for O2 distribution, bleeding regulation, and infection control

What problems are caused by leukemia?

Chemotherapy

Chemical (drug) treatments used to “kill” cancer cells, non-specific elimination of fast growing/multiplying cells

Hormone therapy

Slow growth of cancer cells that utilize hormones for growth; most often used for prostate and breast cancer

Hyperthermia

Heat cancer cells to >113 degrees F

Immunotherapy

Utilizes body’s immune system to fight cancer → block immune system suppression, remove/alter/replace T cells, lab designed antibodies

Photodynamic therapy

Uses light-activated drugs to kill cancer cells, stimulated via laser, only for superficial tumors

Radiation therapy

High dose radiation used to kill cancer via damage to DNA

Stem cell transplants

Used to replace blood stem cells following destruction from chemo/radiation (collect cells, replaced, and re-infused) → rebuild immune system

Hoxsey (herbal) and Gerson (diet, exercise)

Alternative cancer treatments