Introduction to anatomy & physiology: Homeostasis

Question 1

Homeostasis

Answer 1

To maintain dynamic equilibrium in the body controlled by the endocrine and nervous system of mammals. It is dynamic because it is constantly adjusting to the changes that the body’s systems encounter. It is equilibrium because of the bodies functions are kept within specific ranges.

Question 2

Extrinsic regulation

Answer 2

Control systems (the endocrine and nervous system) exist outside of the organs they control, that is, this system can overrise intrinsic systems.

Question 3

Intrinsic regulation

Answer 3

Inherent in an organ, that is, the organ is capable of maintaining homeostasis within itself.

Question 4

Describe the goal of homeostasis

Answer 4

The goal homeostasis is the maintenance of equilibrium around a point of value called a set point through all physiological systems working together to preserve a stable internal environment. While there are normal fluctuations from this set point the body systems will usually attempt to go back to this point.

Question 5

Describe the homeostatic process

Answer 5

A change in the internal external environment is called a stimulus and is detected by a receptor (sensitive to certain environmental change) with the response of the system being to adjust the deviation parameter towards the set point by the effector (responds to commands from the control centre) after receiving the processes and information sent by the control centre (receives and processes information and sends commands).

Question 6

Thermoreceptors

Answer 6

Located in dermis of the skin, skeletal, muscle, liver and hypothalamus and are temperature sensitive.

Question 7

Mechanoreceptors

Answer 7

Sensitive to compression, stretching, and twisting. These include tactile, baroreceptors (respond to change), and proprioceptors (detect changes in pressure).

Question 8

Chemoreceptors

Answer 8

Sensitive to changes in chemical concentration and important for monitoring the pH of the body.

Question 9

Effector

Answer 9

The effector a is a muscle that contracts or relaxes or gland that secretes.

Question 10

Negative feedback loop

Answer 10

Any homeostatic process that changes the direction of the stimulus, that is, it either increases or decreases the stimulus however the stimulus is not allowed to continue as it did before the receptor sensed it.

Question 11

Describe the process of negative feedback mechanism

Answer 11

Disruption to homeostasis occurs, the receptor will detect this change, send information to the command centre, and coordinate a response with the effector to bring about this response.

Question 12

Positive feedback loop

Answer 12

Maintains the direction of the stimulus possibly accelerating it, that is, the directions maintained not changed.

Question 13

Describe the process of the positive feedback mechanism

Answer 13

Disruption to homeostasis occurs, the receptors will detect change, send information to command centre, and the effector will exacerbate away from normal until desired outcome is achieved.

Question 14

Alternation

Answer 14

The possibility to adjust a system set point which happens when the feedback loop works to maintain a new setting and the body no longer recognises the elevation as abnormal and makes no attempt to return it to the lower set point which results in a maintenance of an elevated setpoint which can have harmful effects on the body.

Question 15

Acclimatisation

Answer 15

When changes can be made in a group of body organ systems in order to maintain a set point in another system.

Question 16

Thermoregulation

Answer 16

Is the term given to the body’s ability to maintain a constant body temperature.

Question 17

Ectotherms and homeotherm

Answer 17

Animals that do not control their body temperature are dubbed ectotherms while an animal that maintains a constant body temperature in the face of environmental changes is called a homeotherm.

Question 18

Endotherms

Answer 18

Animals that rely on internal sources for body temperature, but which can exhibit extremes in temperature.

Question 19

List the heat loss mechanisms

Answer 19

Radiation, convection, evaporation, and conduction.

Question 20

Radiation

Answer 20

The emission of electromagnetic heat waves.

Question 21

Convection

Answer 21

Convection currents of air remove heat from the surface of dry skin as the air passes over it.

Question 22

Evaporation

Answer 22

Heat can be removed with liquid from a surface during evaporation which occurs when a mammal sweats.

Question 23

Conduction

Answer 23

Heat will be conducted from one surface to another during direct contact with the surface is.

Question 24

List the heat retention mechanisms

Answer 24

Vasoconstriction, counter-concurrent adoption, and metabolic heat.

Question 25

Vasoconstriction

Answer 25

Reduces blood flow in powerful blood vessels, forcing blood toward the core and the vital organs found there, and conserving heat.

Question 26

Counter-concurrent adaption

Answer 26

Adoption to the circulatory system that enabled them to transfer heat from arteries to veins, warming blood returning to the heart. This prevents cold venous blood for cooling the heart and other internal organs.

Question 27

Metabolic heat

Answer 27

When muscles are contracted, most of the energy from the ATP Houston muscle actions is wasting energy that translates into heat. Severe cold elicits A shivering reflex that generates heat for the body come on additionally many species also have a type of adipose tissue that called brown fat that specialises in generating heat.

Question 28

List the heat gain mechanisms

Answer 28

Shivering thermogenesis and non shivering thermogenesis.

Question 29

Shivering thermogenesis

Answer 29

Increasing muscle tone uses energy, thereby this involuntary muscular activity that augments metabolic heat production.

Question 30

Non shivering thermogenesis

Answer 30

The release of hormones increased metabolic activity, that is, adrenaline and the thyroid hormones increase basal metabolic rate, and activity in the liver and skeletal muscles (adrenaline) promoted glycogen breakdown generating heat.