Endo 5

Question 1

IC and EC Ca ions are essential for several normal biochemical processes

Answer 1

neuromusclar excitation 
blood coagulation
hormone secretion
enzyme activity
ferilization

Question 2

The three major hormones involved in the regulation of Ca and phosphate metabolism

Answer 2

Calcitonin-thyroid galnd
parathyroid hormone- parathyroid gland
vit D3- kindeys

Question 3

PTH action in homeostasis

Answer 3

peptide produced by the parathyroid gland
increases serum Ca mainly by promoting osteoclast activity
secretion of PTH largely determined by serum Ca2t concentration
-decreases in serum Ca and decreased Ca binding to sensitive receptor leads to promotion of PTH secretion

Question 4

is PTH stored

Answer 4

NO secreted continuously

Question 5

What the the following effects have on PTH secretion
hypocalcemia
hypercalcemia
vit D3

Answer 5

hypocalcemia- increases PTH secretion
hypercalcemia- decreases PTH secretion
vitamin D3- decrease PTH secretion

Question 6

Calcitonins effect on Ca homeostasis

Answer 6

peptide produced by thyroid C cells
secreted in response to hypercalcemia, short acting
vitamin D3 inhibits calcitonin secretion
CT lowers serum Ca by inhibiting osteoclast activity

Question 7

Calciferols (vit D)

Answer 7

• enhance absorbance of Ca by the gut and reabsorption of these ions by nephron
• Both PTH and calcitonin increase vitamin D3 synthesis

Question 8

When hormones help increase bone mineralization and growth

Answer 8

GH and IGF-1, thyroid hormones

Question 9

Which hormones oppose PTH actions by slowing turnover of bone

Answer 9

estrogens and androgens

Question 10

Hyperparathyroidism

Answer 10

• hypercalcaemia
• increased bone resorption
• mineralization of soft tissues
• incrased tirst and urination (ca blocks ADH effects)

Question 11

Hypoparathyroidism

Answer 11

hypocalcaemia
muscular weakness, ataxia
cardiac arrhythmias

Question 12

major causes of hyper and hypoparathyroidism

Answer 12

hyper
-primary- hyperplasia, adenoma, genetic
-secondary- kindey failure, vitamin D def
Hypo
-surgery and injuries to the neck
-autoimmune disease
-di-george syndrome
-low Mg levels

Question 13

Rickets

Answer 13

malnutrition resulting in severe calcium and vit D deficiency that occur in young animals
leads to moth malformations, enlarged and weakened joints, costochondral swellings, soft skull

Question 14

Ostemalacia

Answer 14

results of Vit D deficiency and low dietary Ca in older individuals

Question 15

Milk fever

Answer 15

• occurs in dairy cows during periparturient period
• 3-10% of dairy cows may be affected
• may occur in beef cattle
• eclampisa usually affects medium sized dogs with large litters, approx 3-4 weeks after whelping