Lab 8: Animal Biology: Excretory and Digestive Systems Flashcards
Briefly summarise the function of the following organ: mouth
mechanical digestion, starts the break down of starch
Briefly summarise the function of the following organ: esophagus
passageway for bolus that connects to the stomach
Briefly summarise the function of the following organ: stomach
breaks down food mechanically and chemically
Briefly summarise the function of the following organ: small intestine
absorbs the bulk of nutrients
Briefly summarise the function of the following organ: large intestine
absorbs water and other small nutrients
Briefly summarise the function of the following organ: rectum
temporarily stores feces
Briefly summarise the function of the following organ: anus
exit source for waste
Briefly summarise the molecules the following organ secretes/ releases: pancreas
secretes enzymes and sodium bicarbonate to neutralize chyme
Briefly summarise the molecules the following organ secretes/ releases: liver
secretes bile
Briefly summarise the molecules the following organ secretes/ releases: salivary glands
secretes salivary amylase which breaksdown starch
Briefly summarise the molecules the following organ secretes/ releases: gall bladder
secretes excess bile
name the 3 tubes that connect to each kidney
- ureter
- renal artery
- renal vein
Describe the following for the ureter:
- what the tube contains
- which organs these contents came from
- which organ these contents are going to next
- urine
- kidneys
- urinary bladder
Describe the following for the renal artery:
- what the tube contains
- which organs these contents came from
- which organ these contents are going to next
- oxygenated blood
- abdominal aorta
- kidney tissue
Describe the following for the renal vein:
- what the tube contains
- which organs these contents came from
- which organ these contents are going to next
- deoxygenated blood
- kidney
- inferior vena cava
How does the excretory system help you maintain homeostasis when you’re dehydrated? Why is your urine darker coloured when you are thirsty?
the kidneys regulate water levels in urine depending on the needs of the body. When we intake less water we are in shortage of water and less will exit in urine. If we are intake more water than necessary at the time, we will be in a surplus and more will exit in the urine. This is why sometimes urine becomes darker because it gets very concentrated when we are dehydrated.
Explain what happened to the other 158.5 litres of fluid that entered the nephron as glomerular filtrate?
Kidneys regulate water levels by conserving water if you’re dehydrated or diluting urine to expel water if necessary
1.5 litres is still a large volume of fluid for a human being to lose every day. Explain how we replenish this water that we lost from our bodies.
we intake fluid (drinking water!)
water is absorbed by the large intestine
Explain why there is no protein in the glomerular filtrate or the urine
kidneys filter what goes into the urine and proteins are too big to pass through this filter. their molecules are too big
Explain why glucose concentrations are 120mg/100mL in the blood entering and exiting the glomerulus and the glomerular filtrate but absent in the urine.
the kidneys absorb all the glucose and return it to the blood stream
explain why urea concentrations are 30mg/100ml in the blood entering and exiting the glomerulus and in the glomerular filtrate but are 2000mg/100ml in the urine
- urea is a byproduct of the breakdown of nitrogen containing compounds and considered waste in the body. it exits through our urine
Explain the differences in concentration between the arterial blood entering the glomerulus and venous blood exiting the kidney for each solute in table B2. See google doc for table
- proteins: kidneys produce hormones (some are proteins); therefore more leave than enter. proteins cant leave through urine or glomerular filtrate because it is too large
- glucose: kidneys maintain homeostasis by increasing or decreasing the amount of water in urine. the fluid maintenance allows blood glucose levels to maintain consistent
- urea: levels of urea maintained by kidneys which filter it out of body
list in sequential order the enzymes involved with digesting starch into simple sugars. for each enzyme (3) name the oran that produces it and the locations where it is active in digesting food.
- salivary amylase: found in the mouth; produced by salivary glands
- maltase: found in the duodenum; produced by pancreas
- pancreatic amylase: found in the small intestine; produced by pancreas
list in sequential order the enzymes involved with digesting protein into amino acids. for each enzyme, name the organ that produces it, and the locations where it is active in digesting food (3)
- pepsin: found in stomach; produced by stomach glands
- trypsin: small intestine; produced by pancreas
- peptidases: found in small intestine; produced by small intestine
list in sequential order the enzymes involved with digesting DNA/RNA into nitrogenous bases sugars and phosphates. for each enzyme name the organ that produces it, and the locations where it is active in digesting food (2)
- nuclease: active in small intestine; produced by pancreas
2. nucleosidase: active in small intestine; produced by small intestine
list in sequential order the enzymes involved with digesting fats into fatty acids and glycerol. for each enzyme name the organ that produces it, and the locations where it is active in digesting food (2)
- lingual lipase: active in the mouth; produced by salivary glands
- pancreatic lipase: active in duodenum; produced by pancreas
give at least 2 reasons why more than 1 enzyme is necessary for digesting most types of biological molecules
- the breakdown of food is complex, requires multiple steps and multiple enzymes (catabolic pathway)
- depending on the biological molecule; more than 1 enzyme may be necessary if the digestion needs to happen fast
define: excretion
process by which the body removes nitrogenous waste products, deactivated drugs, toxins, and excess solutes from the body
define: homeostasis
state of steady internal, physical, and chemical conditions maintained by living systems
define: osmoregulation
process by which the body balances the intake and loss of water and solutes
define: water intoxication
consuming too much water and losing too many salts through sweating
Explain the 4 functional steps of nephrons
- see google doc
State the enzymes produced in the salivary glands and what their function is (2)
- salivary amylase: breaks apart carbs releasing sugars in the mouth
- lingual lipase: breaks bonds in fats releasing fatty acids and monoglycerides in mouth and stomach
State the enzymes produced in the stomach and what their function is (1)
- pepsin: break peptide bonds between certain amino acids in proteins releasing polypeptides
State the enzymes produce din the pancreas and what their function is (7)
- carboxypeptidase and chymotrypsin and elastase: breaks peptide bonds in polypeptides releasing amino acids in the small intestine
- nucleases: break apart nucleic acids in the small intestine releasing nucleotides
- pancreatic amylase: break apart carbohydrates in the small intestine releasing sugars
- pancreatic lipase: break bonds in fats releasing fatty acids and monoglycerides in small
intestines - trypsin: break specific peptide bonds in polypeptides releasing amino acids in small intestine
State the structures food passes through in the human body (7)
- mouth
- esophagus
- stomach
- small intestine
- cecum
- large intestine
- anus
Trace the path of a single molecule of hemoglobin
coming in through the renal artery.
- renal artery, cortex, medulla, renal vein
In which region of the kidney is
blood filtered to form filtrate?
- renal corpuscle (located in the cortex)
Which region of the kidney has a high osmolarity (i.e., concentration of solutes) that
draws water out of the nephron through osmosis? Which two solutes are primarily
responsible for creating this osmolarity gradient?
- interstitial fluid in the medulla
- Na+ and Cl-
Name the microscopic tubes that “collect’ urine from many nephrons and deliver this
urine into the renal pelvis
- renal calyces
