Regulations of systems

Question 1

acute hypothermia

Answer 1

occurs when a person is suddenly exposed to extreme cold

Question 2

antidiuretic hormone

Answer 2

hormone produced by neurosecretory cells in the hypothalamus; increases reabsorption of water into the blood from distal tubules and collecting ducts of nephrons in the kidney

Question 3

aquaporins

Answer 3

protein channels in the plasma membrane that allow the rapid flow of water into and out of cells

Question 4

autonomic nervous system

Answer 4

the part of the peripheral nervous system associated with involuntary control of bodily functions

Question 5

basal metabolic rate

Answer 5

the minimum amount of heat generated in the body by metabolic processes

Question 6

central nervous system

Answer 6

the part of the nervous system composed of the brain and spinal cord

Question 7

core body temperature

Answer 7

temperature of internal cells of the body; in humans, core temperature is around 37 °C

Question 8

ectothermic

Answer 8

organism whose body temperature is governed by external sources of heat

Question 9

endocrine system

Answer 9

system of ductless glands that produce hormones and release them directly into the bloodstream

Question 10

endothermic

Answer 10

organism whose body heat is generated from internal metabolic sources

Question 11

exhaustion hypothermia

Answer 11

occurs when a person is exposed to a cold environment and cannot generate sufficient metabolic heat to maintain their core body temperature due to exhaustion or lack of food

Question 12

feedback loop

Answer 12

a process in which the response (output) in a stimulus–response action affects the stimulus (input), either increasing or decreasing it

Question 13

glucagon

Answer 13

hormone produced by alpha cells of the pancreas that acts on liver cells resulting in increased release of glucose from the liver cells into the bloodstream

Question 14

gluconeogenesis

Answer 14

cellular production of glucose using non-carbohydrate precursors; occurs mainly in liver cells

Question 14

glycogen

Answer 14

a polysaccharide storage carbohydrate built from glucose; found mainly in liver and muscle tissue

Question 15

heat exhaustion

Answer 15

an increase in core body temperature; symptoms include poor coordination, slower pulse and excessive sweating; may develop into heat stroke

Question 16

heart stroke

Answer 16

a critical and life-threatening condition where brain function is affected; symptoms include high core body temperature in excess of 40 °C, slurred speech, hallucinations and multiple organ damage

Question 17

homeostasis

Answer 17

condition of a relatively stable internal environment maintained within narrow limits

Question 18

hyperglycaemia

Answer 18

a condition where glucose levels in the blood rise above normal

Question 19

hyperthermia

Answer 19

condition in which core body temperature exceeds the upper end of the normal range without any change in the temperature set point

Question 20

hyperthyroidism

Answer 20

condition in which there is an overabundance in thyroid hormone production

Question 21

hypoglycaemia

Answer 21

glucose levels in the blood drop below normal

Question 22

hypothalamus

Answer 22

tiny region of the brain below the thalamus that controls various essential functions, including those associated with the autonomic nervous system

Question 23

hypothermia

Answer 23

condition in which an individual has an extremely low body temperature and is at risk of death

Question 24

hypothyroidism

Answer 24

condition in which there is a deficiency in thyroid hormone production

Question 25

insulin

Answer 25

hormone produced by beta cells of the pancreas that acts to increase the uptake of glucose from the blood by body cells

Question 26

ketones

Answer 26

acid; breakdown product of fat metabolism

Question 26

negative feedback

Answer 26

a regulatory mechanism in which a stimulus results in a response that is opposite in direction to that of the stimulus

Question 27

osmoregulation

Answer 27

process by which the volume of body fluids and their solutes concentrations are controlled

Question 28

oxytocin

Answer 28

a hormone that induces labour and milk release from mammary glands in females

Question 29

pancreases

Answer 29

organ that secretes digestive enzymes into the duodenum and hormones into the bloodstream

Question 30

panting

Answer 30

an increase in breathing rate that acts to reduce body temperature through evaporation

Question 31

peripheral nervous system

Answer 31

the part of the nervous system containing nerves that connect to the central nervous system

Question 32

peripheral surface temperature

Answer 32

temperature of cells on the outside of the body; may be many degrees cooler than core temperature

Question 33

pituitary gland

Answer 33

endocrine gland attached to the hypothalamus; influences the production of thyroxin by the thyroid

Question 34

positive feedback

Answer 34

a process in which the response to a stimulus causes an amplification of the initial change, increasing its level further away from the starting value

Question 34

set point

Answer 34

midpoint of a narrow range of values around which a physiological variable fluctuates in a healthy person

Question 34

shunt vessels

Answer 34

direct connections between arterioles and venules that bypass capillary beds

Question 34

somatic nervous system

Answer 34

the part of the peripheral nervous system associated with voluntary control of movement

Question 35

stimulus-response model

Answer 35

a representation of an action that starts with a stimulus and ends with the response to that stimulus

Question 36

thermograph

Answer 36

an instrument that shows the surface temperature or heat signature of an object

Question 37

thermoregulation

Answer 37

the maintenance of core body temperature

Question 38

thyroid gland

Answer 38

endocrine gland located on the ventral surface of the trachea

Question 39

thyroxine

Answer 39

hormone produced by the thyroid gland that acts to increase the rate of cell metabolism

Question 41

type 1 diabetes

Answer 41

a condition that results when the homeostatic mechanisms that regulate blood glucose levels fail when insulin production fails, characterised by a blood glucose level that is higher than normal

Question 42

vasoconstriction

Answer 42

narrowing of the diameter of blood vessels

Question 43

vasodilation

Answer 43

widening of blood vessels to increase blood flow