Digestion And Excretion

Question 1

Excretion definition

Answer 1

The process by which metabolic wastes are eliminated

Question 2

Organs of excretion

Answer 2

Kidneys
Skin (sweat)
Lungs (waste gases)

Question 3

Kidneys function

Answer 3

-To excrete waste products
-Maintenance of volume and composition of extracellular fluid within narrow physiological limits

Question 4

Extracellular fluid

Answer 4

Blood(plasma)
Interstitial fluid

Question 5

Intracellular

Answer 5

Water 67% of the total body water

Question 6

How do the kidneys perform their function

Answer 6

-stabilising osmolality and volume of extracellular fluid

-Regulating the concentration of extracellular ions

-Removing metabolic wastes and foreign substances

-Maintaining acid base balance

Question 7

List anatomy of the kidney

Answer 7

-Renal capsule
*smooth transparent membrane

-Renal cortex
*outer payed containing functional kidney tissue

-Renal medulla
*inner layer contains tubular tissue

-Calyces
*minor collecting ducts that combine into the major
*Major

-Renal pelvis
*Expanded area of ureter

-Ureter

-Blood supply

Question 8

Definition of Digestion

Answer 8

The process by which food is broken down into molecules small enough to be absorbed by the body

Question 9

Components of the GI tract

Answer 9

Head
-teeth and salivary glands
Oesophagus
Stomach
-corpus, fundus, pylorus
Small intestine
-Duodenum, jejunum, ileum
Accessory organs
- liver/gall bladder
- Pancreas
Large intestine
- caecum, proximal/transverse/distal colon, rectum

Question 10

Definition of egestion

Answer 10

Undigested waste material that’s eliminated

Question 11

List salivary glands

Answer 11

-parotid = serous
-mandibular, Sublingual, buccal= mixed mucous and serous
-zygomatic = mucous (carnivores only)

Question 12

Simple stomach animal

Answer 12

-Mucous aid food passage
-PH neutral to allow action of amylase

Question 13

Complex stomach animals (ruminants)

Answer 13

-mainly serous to give optimum conditions for fermentation
-PH alkaline to buffer forestomach
-copious secretions

Question 14

Components of saliva

Answer 14

-Mucin
-Amylase (omnivore/horse/ruminant)
-Bicarbonate
-Phosphate (ruminants)
-Lysozyme
-Protein binding tannins (leaf and bud eaters)
-Urea (ruminants)

Question 15

Secretion of saliva in non ruminants

Answer 15

-isotonic with blood

-at low flow rates becomes hypotonic

-at high flow rates remains isotonic

Question 16

Secretion of saliva in ruminants

Answer 16

-secretion always isotonic
-low flow rates po4 dominates
-high flow rates HCO3 dominates

Question 17

Composition of fluid in the abdomen

Answer 17

-mucus
-enzymes for chemical breakdown of food
-ions and pH appropriate for digestive enzymes

Question 18

Enzymes that break down carbohydrates and where are they secreted

Answer 18

Amylase, disaccharidases
-saliva, Pancreas, intestinal mucosal surface

Question 19

Enzymes that break down proteins and where are they secreted

Answer 19

Pepsin, trypsin, peptidases
-glands of stomach, Pancreas, intestinal mucosal surface

Question 20

Enzymes that break down fats and where are they secreted

Answer 20

Lipase, phospholipase
-Pancreas, intestinal mucosal surface

Question 21

3 main functions of the kidney

Answer 21

Filtration
- Glomerulus

Reabsorption
- Tubules

Secretion
- Tubules

Question 22

Two main parts of the Nephron

Answer 22

• Glomerulus
  -Tubular System

Question 23

What does the Glomerulus consist of

Answer 23

• Afferent arteriole
  (bringing blood too)
• parallel capillaries with interconnections located within the bowman’s capsule
• Efferent arteriole
• peritubular capillaries
  (form a network to take away he products of reabsorbtion)

Question 24

What does the tubular tissue consist of

Answer 24

• Bowman’s space

-proximal tubule

-loop of henle

• distal tubule

-collecting duct