Bio 118 - Exam 1

What information can be obtained from a CBC and blood chemistries?

blood cell numbers and blood content

pluripotent

can be grown into any kind of tissue in the body

multipotent stem cells

can differentiate into tissue specific cells

induced pluripotent

pluripotent stem cells that are mature stem cells that are reprogrammed

homeostatic control systems

1. Stimulus

2. Receptor

3. control center

4. effector

5. Response

Keep the body balanced with negative feedback

What is physiology and how does it differ from anatomy?

Physiology is the study of how the body and its parts function, anatomy is just the study of structures.

levels of organization of the human body

1. chemical

2. cellular

3. tissue

4. organ

5. organ system

6. organism

What are emergent properties?

characteristics that appear only when smaller parts combine to form a whole system (heart cell vs pumping, brain vs consciousness)

How do social factors influence your physiology?

factors like environment and access to healthcare affect your physiology

Is race a genetic or social construct? What is the vitamin D-folate hypothesis?

Race is a social construct. vitamin D-folate hypothesis= UV light is needed for vitamin D production, but also degrades folate. ppl near equator have darker skin to protect from harm, people far from equator have lighter skin to get enough vitamin D

Why are B vitamins important in the human body?

without them brain cells would die, they reduce inflammation and help glucose metabolism

anion

negatively charged ion

Cation

positively charged ion

Compare ionic vs. covalent bonds in the context of physiology. Which type of bond readily dissociates (breaks apart) in water?

Ionic bonds: the transfer of electron(s) to another atom (break in water)

Covalent bonds: the sharing of electron(s) between two atoms (stronger)

Which ions are most important in the human body? What are their functions?

H+: pH regulation

Ca2+: membrane function, nerve impulses, muscle contraction, blood clotting

PO3-4: found in bones, teeth, nucleic acid, and high energy compounds

K+: proper membrane function, nerve impulses, muscle contraction

Na: blood volume, membrane function, nerve impulses, muscle contraction

Cl-: blood volume, membrane function, water absorption

Mg2+: cofactor for enzymes

I-: component of hormones in thyroid

What is the difference between sodium atom (Na) vs. sodium ion (Na+) or chlorine atom(Cl) vs. chloride ion (Cl-)

Na is neutral and has 11 protons and electrons; Na+ is positive and has 11 protons and 10 electrons

Cl is neutral and has 17 protons and 17 electrons; Cl- is negative and has 17 protons and 18 electrons

What is flux and why is this a useful concept for understanding physiology?

Flux: movement of a substance between compartments, a useful concept because of diffusion across membranes

What chemical properties & pH values define acids? define bases?

Acids: proton donators, sour, pH < 7

Bases: proton acceptors, bitter, pH of > 7

Why is 7.0 neutral? Compare the relative acidity of different pH values

7 is neutral because there is an equal level of acidity and basic

What is normal blood pH?

7.35 - 7.45

How does your body normally fix small deviations in pH? Be able to explain the specific roles of buffers, the respiratory system, and the urinary system

Buffers: The body normally uses buffers to regulate small deviations in pH, HCO3- binds to H+ to form H2CO3, which breaks down into CO2 and H2O

Respiratory system: has the ability to breathe out more CO2 which reduces the level of H+ in the bloodstream

Urinary system: can increase/decrease the level of acidity in urine to combat pH change

What are some common causes of acidosis?

Acidosis: diarrhea, metabolic acidosis, elevated CO2 due to asthma, emphysema

What is the bicarbonate buffer system? What causes carbonic acid to form in the blood?

CO₂ + H₂O ⇄ H₂CO₃; H₂CO₃ ⇌ HCO₃⁻ + H⁺

carbonic acid forms when there is a change from normal blood pH levels

Describe how ventilation can alter pH

someone is breathing too fast they’re exhaling a lot of carbon which causes their pH to increase, because of Le Chatelier's principle the body works to get it back to equilibrium and slows breathing or breaks down carbonic acid to lower the pH level

What is homeostasis? How can you use homeostasis models to understand acidosis?

body at equilibrium, he body is at homeostasis then a stimulus changes that and you enter acidosis, chemoreceptors pick up on this and signal it to the brain which sends a signal to the lungs which start breathing faster to release CO2 and increase the pH level

acidosis

main organs of the digestive system? (8)

Mouth, esophagus, stomach, liver, gallbladder, pancreas, small intestine, large intestine

Mouth function

break up food particles

pharynx function

swallows

salivary glands function

saliva moistens and lubricates food, amylase digests polysaccharides

esophagus function

transports food

stomach function

stores and churns food, pepsin digests protein, HCI activates enzymes, breaks up food, kills germs, limited absorption

liver function

breaks down and builds up many biological molecules, stores vitamins and iron, destroys old blood cells, destroys poisons, produces bile

gallbladder function

stores and concentrates bile

pancreas function

hormones regulate blood glucose levels, bicarbonates neutralize stomach acid, secretes enzymes: protease, lipase, and amylase

amylase

breaks down carbs

lipase

breaks down lipids

protease

breaks down protein

small intestine function

completes digestion, absorbs nutrients, peptidase digests protein, sucrases digest sugars, amylases digest polysaccharides

large intestine function

reabsorbs some water and ions, forms and stores feces

rectum

stores and expels feces

Explain the difference between mechanical & chemical breakdown of food by the digestive system.

Mechanical breakdown of food is the physical breakdown of foo like chewing. chemical breakdown is the actual breakdown of the bonds in the food

Explain the roles of smooth muscle tissue in the movement of food through the digestive system as well as mechanical breakdown of food.

smooth muscle contracts in a coordinated way to propel food through the digestive system, it contracts in the stomach to mush food into smaller pieces

secretion

body producing and releasing substances to break down food

Compare the roles of bile (salts) from the liver, and pancreatic enzymes in digestion. Why are these introduced into the first part of the small intestine?

Bile aids with mechanical digestion, enzymes aid with chemical digestion. They are introduced in the first part of the small intestine so everything can be digested before it has to be absorbed

Which health conditions are associated with pancreatitis and what are its effects?

Associated health conditions: diabetes, obesity, smoking

Effects: inflamed pancreas, diarrhea

What are the main differences between a non-alcoholic fatty liver, non-alcoholic steatohepatitis, and cirrhosis?

NAFL: just fat build up, reversible

NAS: fat build up, inflammation, dying hepatocytes, reverse possible in early stages

Cirrhosis: scar tissue replaces healthy, irreversible

How does a bolus of food differ from chyme

a bolus is the physical ball of food you swallow, chyme is the juice mix of broken down food being churned in your stomach

How does peristalsis through the esophagus differ from propulsion, grinding, and retropulsion in the stomach?

Peristalsis: circular muscles constrict esophagus behind food, longitudinal muscles contract pushes food forward

Propulsion:peristaltic waves move the fundus toward the pylorus

Grinding: most vigorous peristalsis occurs close to pylorus, acts as a pump that delivers small amounts of chyme to duodenum

Retropulsion: peristaltic wave closes pyloric valve, forces most of contents back into stomach

Which characteristics of the small intestine help with absorption of nutrients?

the circular folds slow chyme movement, the villi and microvilli

How do secretions from other digestive organs affect digestion in the small intestine?

secretions from other organs like enzymes from the pancreas help the small intestine neutralize stomach acid, and digest food

What are the three main macromolecules in food?

Carbs, lipids, proteins

How can metabolism be explained using a mass balance model?

everything that is put into your body needs to be broken down and stored (metabolism) or excreted

Glycogenolysis

Glycogen is converted to glucose through a catabolic process, when blood sugar is low

What is the chemical structure of carbohydrates?

CH2O ring shape, two hydrogen for every carbon and oxygen

What are the effects of eating a lot of cellulose and why does it cause these effects?

Causes a lot of poop because the body cannot break it down into glucose, so it must be passed

What is the difference between lactose and lactase? Which type of carbohydrate is lactose and what needs to happen in the body before it can be absorbed?

Lactose is milk sugar and lactase is the enzyme that breaks it down. Lactose is a disaccharide, so it needs to be broken down into simple sugars before it can be absorbed.

What is lactase persistence and what led to human variation in this trait? What are some health equity issues related to lactase persistence?

Lactase persistence is the ability to continue digesting lactose as you age. This happens because people live in places with high dairy cow percentages. Lack of calcium leads to osteoporosis.

Compare the 3-dimensional structures of glycogen, cellulose & starch. What do those structures tell you about the storage function of each type of carbohydrate? Which complex carbohydrate is most rapidly catabolized by enzymes? Explain why.

Glycogen is heavily branched for easy access to breakdown for glucose. Starch has amylose that's unbranched and amylopectin that is branched, fewer branches but still access to break down. Cellulose is linear we cannot break it down. glycogen is most rapidly catabolized because it has the most branches.

explain why cell membranes are selectively permeable and which substances can cross the membrane most easily

Cell membranes are made up of a phospholipid bilayer. This bilayer is made of fats, anything that’s hydrophilic can’t pass. Hydrophobic and small, uncharged polar molecules can easily get through.

polar covalent bonds

polar covalent bonds are when electrons are shared unevenly, charged, often with oxygen and nitrogen, (hydrophilic)

How can you tell whether a cellular transport mechanism involves active or passive transport? Which forms of passive transport use carrier proteins?

It involves active transport if it requires ATP (usually from low to high concentration)

Carrier proteins are used during facilitated diffusion

After enzymes from the intestine and pancreas break down carbohydrates, where do they go and how do they get there? Which type of cellular transport is used to transport glucose from high concentrations to low concentrations?

Carbohydrates are broken down by lactase and others and use facilitated diffusion to enter the cell, they become monosaccharides and undergo facilitated diffusion again to leave the cell and enter the blood stream. Passive transport

Where is insulin produced and how does it affect glucose transport?

produced in the pancreas, it must bind to a receptor protein before glucose can enter a cell

Type 1 diabetes

Patients have no insulin being produced

Type II diabetes

Patients have desensitization to insulin

How do incretin hormones affect insulin release and appetite?

They increase the amount of insulin produced and repress appetite

How and where are proteins broken down? What is produced by this breakdown and how arethese substances transported into the blood?

Proteins are broken down in the stomach by pepsin and in the small intestine by enzymes. They are broken down into polypeptides and enter the cell through facilitated diffusion and cotransport, broken down into monomers called amino acids

How and where are lipids broken down? How are chemical and mechanical digestion used to break lipids into fatty acids and monoglycerides? Where do they go after they are broken down?

Lipids are broken down in the small intestine, they are emulsified by bile salts and then broken down by enzymes. They go into the lymphatic system when they are broken down and are called lacteals

What do pancreatic beta cells do?

detect glucose levels and release insulin

What does the pancreas release into the small intestine?

bicarbonate and enzymes

How do lipids enter cells?

They go straight through (simple diffusion)

Ions

charged particles

Electrolyte

ions that dissociate in water

What are are some common causes of alkalosis?

Alkalosis: vomiting, breathing too quickly, panic attack, fever

Digestion function

breakdown of food

absorption function

uptake of nutrients and other things into the blood

How can the liver contribute to glycogenolysis and glycogenesis?

Liver breaks down glycogen to glucose to increase blood glucose (glycogenolysis) OR liver converts glucose to glycogen when blood sugar is high (glycogenesis)

Glycogenesis

anabolic process converting glucose back into glycogen for storage when blood sugar is high

Non-polar covalent bonds

non-polar covalent bonds are when electrons spend equal time near each nucleus, both nuclei have the same charge (hydrophobic)

pH

concentration of hydrogen

stem cells

cells that are undifferentiated (don’t have a specific job/function), are used to replace worn out cells when they die

relationship between pH and H

inverse relationship pH high= H is low (vice versa). Acidic is on the left scale (low pH and high H) and basic is on the right (high pH and low H) A before B

symptoms of acidosis

inhibits brain, muscle fatigue, coma (diarrhea, metabolic acidosis, elevated CO2 due to asthma)

symptoms of alkalosis

excites brain, muscle twitch, convulsions (vomiting, breathing too quickly, fever)

normal urine pH

4.5-8

buffers of pH

carbonic acid, protein buffers, phosphate buffers, hemoglobin

synthesis reaction

forming larger molecule

decomposition reaction

breaking down larger molecule

exchange reaction

simultaneous synthesis and decomposition reactions because molecule parts switch around