Chapter 4: Water Flashcards
Water
- explain structure
Polar nature gives it a v shape; positive hydrogen atoms and negative oxygen atoms
Describe the water content of the human body
- 60-70% of the body is water by weight
intracellular: 2/3 - A cell’s cytoplasm is 80% water; water in cytoplasm accounts for the majority of the body’s water
extracellular: 1/3 - blood, around joints, lining tissues around lungs, lymph, between cells
fill in the blank: blood is ___ water
90%
Explain how water is exchanged between the extracellular space and the blood (2)
- Osmosis: movement of water across semi permeable membranes to even out concentration differences
- blood pressure: force pushes water out of blood and into the extracellular space
List the functions of water (6)
- structure
- solvent
- hydrolysis
- defence from infection
- protection from injury
- temperature regulation
Explain how water provides structure
- Gives cells 3 dimensional shape to function properly with water pressure
- Synovial fluid in sacs between joints promote joint structure and allow bones to glide by each other more fluidly
- Fluid in eye gives it structure
Explain how water serves as a solvent
- Dissolves polar substances allowing them to be more easily transported around body through a medium into passageways (digestive tract or blood vessels)
- Compatible reactants dissolved in water have an increased chance of them colliding and undergoing a chemical reaction
Explain water’s role in hydrolysis
- Process of splitting larger molecules into smaller ones using water
- Example: maltose → 2 glucose molecules
Explain water’s role in defence from infection (2)
- Infectious agents are moved to the lymph where immune cells act on them
- Mucus traps and gathers pathogens for removal
Explain water’s role in injury protection
- Reduces the friction and damage from movement or trauma
- Water in synovial fluid prevents bones from scraping against each other
- Mucus protects tissues from injuries
- Cerebrospinal fluid protects brain from various forces
Explain water’s role in temperature regulation
- Internal temperature for proper function: 37degC
- Body opens blood vessels near skin to allow blood to shunt heat from the body’s core to the skins surface . This triggers the sweat response. Also contributes to the observable redness of our skin when exercising
- Sweating: released water on skins surface cools our bodies and skin as it evaporates
What are ways we lose water (3) and gain water (3)
lose: urine, feces, evaporation
gain: beverages, foods, metabolic processes (hydrolysis)
What 2 mechanisms come to play when blood volume decreases
- Thirst increases
- Kidneys gatekeep what stays in blood and is excreted in urine
(High blood volume → excess water is excreted in kidneys)
(Low blood volume + pressure → kidneys decrease urine production)
Dehydration
- symptoms
- what does chronic dehydration put you at risk for?
- symptoms: increased thirst, dry mouth, headaches, fatigue, dizziness, irritability, dark urine
- kidney disease, seizures, hypovolemic shock
Water intoxication
- what
- hyponatremia
- symptoms
- Content of water in body is too high with respect to the level of electrolytes
- Occurs when you consume too much water too fast or when you lose alot of water from sweating, diarrhea or vomiting and only replace it with more water (need electrolytes!)
- Hyponatremia: too much water in relation to sodium in the body
- Symptoms: headache, confusion, personality changes, irritability, drowsiness, malfunction of the CNS, increased risk for seizures, brain damage, coma, death
Fill in the blank: Water loss of _____ of body weight can lead to death
10-20%
List some diuretics
- water pills
- caffeine
- alcohol
Explain how water pills are a diuretic and when they’re prescribed
- Aka water pills; prescribed for high blood pressure, kidney stones, tissue swelling
- Promote sodium excretion and therefore water excretion
Caffeine
- effects
- diuretic effect risk
- benefits
- Promotes alertness, reduce fatigue and drowsiness
- Diuretic side effect of caffeine may increase risk for miscarriage and kidney problems
- Contains antioxidant and anti-inflammatory properties
- Meta analysis review found that coffee probably reduced to decreased risk of cardiovascular disease, parkinson’s disease, type 2 diabetes, and some cancers
Alcohol
- risks
- benefits
- kcal/g
- Risks: increases risk of liver cirrhosis, liver cancers, digestive cancers, confusion, dementia
- Drinking alcohol impairs the absorption of several micronutrients
- Light to moderate consumption of alcohol may reduce risk of cardiovascular disease
- Provides 7kcal/g
Factors that affect level of intoxication
- How much consumed
- How quickly the alcohol is absorbed (fizzy drinks and empty stomachs)
- Size of the individual
- Gender
- Genetic factors
- Type of alcohol consumed
- Menstruation cycle
How is alcohol metabolized? list the pathway
- 90% of alcohol is metabolized and eliminated at the liver; enzymes at play: alcohol dehydrogenase and aldehyde dehydrogenase
- see google doc
Hangovers
- symptoms
- how
- Symptoms: vomiting, tiredness, decreased attention, decreased concentration, stomach pain, disturbed sleep
- Presence of congeners, acetaldehyde buildup, and the direct effect of alcohol are likely the cause of hangover symptoms
- congeners (substance added during fermentation process)
What are some water recommendations (3)
- AI
- Adequate intake (AI): women 2.7L/day and men 3.7L/day
- Look for signs of dehydration: thirst, headache, dark yellow urine
- Replenish water and electrolytes when excessive water is lost through sweating, vomiting, and/or diarrhea
Describe the western and indigenous lens on water
Western lens - Important natural resource - Commodity - Used for industry, agriculture - Used by humans as a nutrient Indigenous lens - Tied to our existence - Part of who we are - Has a life of its own - Mother life’s blood
What happened with the Whanganui River
140 year long lobbying effort resulted in the New Zealand river given the same legal rights as humans
How is Canada decolonizing water?
- Aim: create a community based water governance system led by indigenous individuals and rooted in Indigenous law
- Example: indigenous led collection of water samples along the Yukon River
