10.3.1 Hunger 2

Question 1

When the blood glucose level starts to fall, the ____ converts some of its glycogen back to glucose. In this way blood glucose levels stay fairly steady for most people most of the time.

Answer 1

liver

Question 2

To pancreatic hormones, insulin and ____, regulate the flow of glucose.

Answer 2

glucagon

Question 3

____ enables glucose to into the cells, except for brain cells, where glucose does not need insulin to enter. When insulin levels are high, glucose enters cells easily.

Answer 3

Insulin

Question 4

When someone is getting ready for a ____, insulin levels rise, letting some of the blood glucose into the cells in preparation for the rush of additional glucose about enter the blood.

Answer 4

meal

Question 5

Insulin continues to increase during and after a meal. In general, high levels of insulin ____ appetite, because insulin enables so much glucose to into the cell. When much glucose is already entering the cells, you don’t need to eat more.

Answer 5

decrease

Question 6

As time passes after a meal, the blood glucose level falls. Therefore, insulin levels drop, glucose injures the cells more slowly, and ____ increases.

Answer 6

hunger

Question 7

____ stimulates the liver to convert some of it stored glycogen into glucose to replenish low supplies in the blood.

Answer 7

Glucagon

Question 8

If the insulin level stays constantly ____, the body continues moving blood glucose into the cells, including the liver cells and the fat cells, long after a meal.

Answer 8

high

Question 9

Before too long, ____ ____ drops, because glucose is leaving the blood without any new glucose entering. In this case, despite the high insulin level, hunger increases.

Answer 9

blood glucose

Question 10

If the insulin level remains low, as in people with ____, blood glucose levels may be three or more times the normal level, but little of it enters the cells.

Answer 10

diabetes

Question 11

People and animals with diabetes eat more food than normal because their cells are starving, but they excrete most of the glucose, and they ____ ____.

Answer 11

lose weight

Question 12

Note that either prolonged high or prolonged low insulin levels ____ ____, but for different reasons and with different effects on body weight.

Answer 12

increased eating

Question 13

If you consistently eat either a little more or less than necessary, eventually, you would be much too heavy or much to thin. The body needs to compensate for day-to-day mistakes by some sort of long-term regulation. It does so by monitoring ___ ____.

Answer 13

fat supplies

Question 14

____ signals your brain about your fat reserves, providing a long-term indicator of whether you have been overeating or undereating. Each meal also releases leptin, so the amount of circulating leptin indicates something about short-term nutrition as well.

Answer 14

Leptin

Question 15

If you have enough fat supplies, you can afford to devote energy to your immune system. If you have no fat, you are starving and you have to ____ ____ whenever you can.

Answer 15

conserve energy

Question 16

Researchers soon discovered that almost all ____ people already produce plenty of leptin. The problem is that they have become less sensitive to it.

Answer 16

overweight

Question 17

Leptin sensitivity declines during ____ and in animals preparing for hibernation.

Answer 17

pregnancy

Question 18

Unfortunately, leptin sensitivity also declines as a result of ____.

Answer 18

obesity

Question 19

When consistent overeating leads to obesity, it damages the ____ ____ (a cell constituent) in the neurons of the hypothalamus, setting in motion a series of outcomes that lead to decreased leptin sensitivity.

Answer 19

endoplasmic reticulum

Question 20

So far, the only way to undo that effect is ____ ____, which increases production of certain chemicals of the immune system. Those chemicals help repair the endoplasmic reticulum.

Answer 20

physical exercise

Question 21

____ depends on the contents of your stomach and intestines, the availability of glucose to the cells, and your body’s fat supplies, as well as your health and body temperature.

Answer 21

Hunger

Question 22

The key brain areas in hunger include several nuclei of the ____.

Answer 22

hypothalamus

Question 23

Many kinds of information impinge onto two kinds of cells in the arcuate nucleus of the hypothalamus, which is regarded as the master area for ____ of ____. Axons extend from the arcuate nucleus to other areas of the hypothalamus

Answer 23

control of appetite

Question 24

The ____ ____ of the hypothalamus has one set of neurons sensitive to hunger signals and a second set sensitive to satiety signals.

Answer 24

arcuate nucleus

Question 25

The hunger-sensitive cells receive input from the ____ ____, and you have surely noticed that good-tasting foods stimulate your hunger. Another input to the hunger-sensitive cells comes from axons releasing the neurotransmitter ghrelin.

Answer 25

taste pathway

Question 26

The stomach releases ____ during a period of food deprivation, where it triggers stomach contractions. Ghrelin also acts on the hypothalamus to decreased appetite and acts on the hippocampus to enhance learning.

Answer 26

ghrelin

Question 27

Where is the digestive system secretes several hormones that signal satiety, ghrelin is the only known ____ ____.

Answer 27

hunger hormone

Question 28

____ has become a serious problem in more and more countries. Simultaneously, other people suffer from ____, in which they refuse to eat enough to survive, or ____, in which they alternate between eating too much and eating too little.

Answer 28

Obesity : anorexia : bulimia