Bio Class 9

Question 1

Excretory Organs

Answer 1

Colon
- digests solid waste

Liver
- digests hydrophobic waste (waste not absorbed or dissolved in blood)

Kidney

• digests hydrophilic waste
• deals with urine production & excretion
• BP regulation, fluid osmotic balance, pH regulation, activation of vitamin D, stimulating RBC through producing erythropoiten, filtration

Question 2

Urinary Organs

Answer 2

Adrenal gland (found on top of kidneys)
Kidney (2)
Ureter
Bladder
Urethra

Question 3

Internal vs Extern urinary sphincter

Answer 3

Internal

• involuntary
• smooth muscles

External

• voluntary
• skeletal muscle (striated)

Question 4

Functional Unit of kidney

Answer 4

nephron

- has millions of nephrons

Question 5

If reabsorbing water, is a shallow or deep nephron better?

Answer 5

Deep because it will increase in osmolarity the deeper you go into medulla

Question 6

Renal pelvis

Answer 6

Urine is dumped

Question 7

Ureter

Answer 7

Connects the kidney to bladder

Question 8

Reabsorption vs secretion

Answer 8

Reabsorption
- nephron into blood

Secretion
- blood into nephron

Question 9

Filtration

Answer 9

moving substance across membrane using pressure

Question 10

Reabsorption

Answer 10

Moving substance from filtrate to blood

• glucose, water, amino acids are reabsorbed
• Na+, HCO3- are reabsorbed *
• K+, H+ are reabsorbed*
• depends on body’s need

Question 11

Secretion

Answer 11

Moving substance from blood to filtrate

• drugs, toxins, creatine
• Na+, HCO3- are secreted *
• K+, H+ are secreted*
• depends on body’s need

Question 12

If the body is acidic, what will it secrete? What will it absorb?

Answer 12

It will secrete H+ and absorb HCO3-

Question 13

Creatine

Answer 13

Waste product from muscle metabolism

- creatine formation and secretion is constant so you can use it to measure function of kidney

Question 14

What happens in the nephron?

Answer 14

1. Blood coming into glomerulus via afferent arteriole and exits via efferent arteriole
2. The blood plasma is filtered out and enters the capsule because of the pressure and is not called the filtrate
3. Enters proximal convulted tubule which is the main reabsorption and secretion site, relatively unregulated
4. Then enters descending loop of henle which is where water reabsorption occurs and it is impermeable to Na+; therefore osmolarity increases
5. Then enters ascending loop of henle which is where Na+ reabsorption occurs and is impermeable to water so osmolarity decreases
6. Then enters distal convulted tubule which is specialized reabsorption and secretion
   - 2 main hormones but mostly aldosterone (which increases Na+ reabsorption and k+ secretion)
7. Then exits through collecting duct where ADH/vasopressin reabsorbs water

Question 15

Relationship between:
urine & blood
volume and concentration

Answer 15

If urine volume increases, blood volume decreases BUT urine concentration decreases and blood concentration increases

Question 16

Renin angiotensin system

Answer 16

• Angiotensinogen is a zymogen that is inactive and produced by liver
• When BP is low, kidney will release renin which activated angiotensinogen to angiotensin I
• Then you have the lungs secreting angiotensin converting enzyme which will then cause angiotensin I to make angiotensin II
• as a result you will have vessel constriction (which means BP increases) AND increase in aldosterone release (Which means more Na+ in blood = increase in ADH to have more water = more blood volume = bp increases)

Question 17

Atrial natriuretic peptide/factor

Answer 17

Opposite of Renin angiotensin system

• High BP so atria is stretched
• RA then releases ANP
• As a result it inhibits Aldosterone release (so decreases BP) AND vessel dilation (so decreases BP) AND inhibits renin release (blocks the JGA so decreases BP)

Question 18

pH regulation

Answer 18

Renal regulation of blood pH is slow so lungs regulate blood pH

Question 19

Juxtaglomerular apparatus

Answer 19

contact point between afferent arteriole & distal convuluted tubule

Afferent arteriole

• baroreceptors
• release of renin if BP is low

Distal convuluted tubule
- chemoreceptors

Question 20

Alimentary Canal

Answer 20

“GI tract”

- tube from mouth to anus

Question 21

Accessory Organs

Answer 21

• digestive role but not part of alimentary canal

- liver, gallbladder, pancrease

Question 22

Liver

Answer 22

produces bile & emulsifies fat

- bile itself does not digest the fat but it breaks the fat into pieces so that lipase can work on it more

Question 23

Gallbladder

Answer 23

Stores and concentrates bile made by liver
- if you don’t have gall bladder it’s okay, it’ll just make digestion harder in the beginning but bile duct will enlarge after

Question 24

Pancreas

Answer 24

Endocrine Role
- produces insulin and glucagon

Exocrine Role

• produces digestive enzymes
• produces bicarb (to neutralize food coming from stomach which is acidic)

Question 25

Digestive enzymes

Answer 25

Lipases - digests lipids/fat Amylase - digests carbohydrates, specifically starch Protease - digests amino acids/proteins Nuclease - digests nucleic acids

Question 26

Alimentary Canal Wall

Answer 26

Lumen (where food is) --> mucosa (epithelial tissue) --> submucosa (connective tissue) --> circular muscle tissue (contracts to decrease diameter of small intestine) --> longitudinal muscle tissue (contracts to shorten small intestine) --> serosa (connective tissue

Question 27

Mouth | - function, structure, exocrine, endocrine

Answer 27

Function - grinds & moistens food - mostly starch digestion, little bit lipid digestion Structure - Teeth - Tongue - Salivary glands (which produces saliva) Exocrine - saliva: mucus & water - lingual lipase: digests lipids - amylase: digests starch - lysozyme: antibacterial (breaks down bacteria cell wall) Endocrine NONE

Question 28

Esophogus | - function, structure, exocrine, endocrine

Answer 28

Function - tube from mouth to stomach Structure - Starts with skeletal then smooth muscle (skeletal because initiates swallowing which is voluntary) - Cardiac sphincter (prevents acid reflux between esophogus and stomach) Exocrine NONE Endocrine NONE

Question 29

Stomach | - function, structure, exocrine, endocrine

Answer 29

Function - store food, acid hydrolysis, grinding Structure 1. Gastric Gland - spread out on walls of stomach (chief cells, parietal cells, mucus cells 2. Pyloric Sphincter - between the stomach & SI; regulates entry of food into small intestine Exocrine - Chief cells release pepsinogen which as it climbs up gastric gland it comes into contact with HCl released by parietal cells - this activates pepsinogen to pepsin - to prevent work of pepsin on wall, mucus cells produce mucus because otherwise pepsin will digest stomach wall and cause bleeding and pain Endocrine G cells produce the hormone called gastrin - increases release of food from stomach to small intestine - stimulates gastric gland - trigger to shut it off is too much food in SI and if pH is acidic because don't want to release more acid into stomach

Question 30

Small intestine | - function, structure, exocrine, endocrine

Answer 30

Function - digestion & absorption Structure - Duodenum (5%), Jejunum (40%, Ileum (55%) - Increase in SA (plicae which have villi, each villus has microvilli which have brush boarders) Exocrine - Trypsinogen --> Trypsin in presence of enterokinase - brush boarder enzyme: disaccharidases & dipeptidases Endocrine - Enterogastrone: decreases release of food from stomach to small intestine (trigger is full small intestine) - secretin: increases bicarb release (trigger is if pH is acidic) - CCK: increases bile release (trigger is fat)

Question 31

Large intestine | - function, structure, exocrine, endocrine

Answer 31

Function - stores feces & water absorption Structure - bacteria & vit k relationship - Ileocecal valve: valve between ileum & cecum which is normally closed but opens and relaxes in presence of food in stomach - internal & external anal sphincters Exocrine NONE Endocrine NONE