Homeostatis and Hypothalamus 1

Question 1

What are Maslow’s Hierarchy of needs?

Answer 1

1. Physiological (food, water)- maintain homeostasis and stay alive
2. Safety needs ( shelter, survival)
3. Social needs( love, friendship, approval)
4. Esteem needs (feelings of self worth)
5. Self-actulization ( becoming our ideal self)

Question 2

What is the drive reduction Theory?

Answer 2

Behaviors are motivated by the drive to maintain biological homeostasis. When a biological need arises, we feel an internal tension.

Question 3

What is an example of the drive reduction theory?

Answer 3

We eat when we are hungry and find warmth when we are cold.

Question 4

What are the other types of drives?

Answer 4

Survival: hunger, thirst, warmth
Reproduction: Sex, Affection
Social: Affiliation, Approval, Self-Esteem

Question 5

What are the functions of the hypothalamus?

Answer 5

Regulate the body’s homeostasis, regulate autonomic and endocrine systems. It is connected to the pituitary and pineal gland.

Question 6

What drives does the hypothalamus regulate?

Answer 6

Hunger, Thirst, Sleep
Body temp, blood presuure
Sexual desire
Reward motivation
Stress Responses
Basal Metabolism
Set point

Question 7

What does the hypothalamus trigger when energy stores are low?

Answer 7

Triggers release of the hormone ghrelin which motivates eating behavior.

Question 8

What does the hypothalamus trigger when energy stores are high?

Answer 8

Triggers realize of the hormone leptin which reduces appetite.

Question 9

What is basal metabolism?

Answer 9

how the body uses and burns calories by default.

Question 10

What is set point?

Answer 10

Body’s naturally preferred weight. Genetic differences can impact basal metabolism and set point (body shape, distribution of fat cells).

Question 11

What does the hypothalamus regulate in terms of sexual desires for both men and women?

Answer 11

GnRh- Gonadotropin releasing hormone.

Question 12

What are the other sex hormones that are regulated?

Answer 12

Testosterone, estrogen, progesterone. “Bonding” hormones like oxytocin as well.

Question 13

What hormone increases sexual desire in both men and women?

Answer 13

Testosterone.

Question 14

What was the difference found in gay and straight men?

Answer 14

Difference in hypothalamic areas.

Question 15

Stress is a deviation from…

Answer 15

Homeostatis
- metabolic priorities shift
-physical and mental energy redirected

Question 16

What systems does stress effect in the body?

Answer 16

Affects most systems in the body
- nervous system
- musculoskeletal system
- cardiovascular system
-gastrintestinal system
-endocrine system
-reproductive system
-immune system

Question 17

What does stress mentally impact?

Answer 17

it impacts attention, perception, memories, emotions

Question 18

What are homeostatic systems maintained or changed by?

Answer 18

Maintained or Changed by “control loop”.

Question 19

What do Control Loops involve?

Answer 19

1)Measurement
-sensors, receptors
-ex. Receptors that detect body temperature
2)Comparison
-Set points, goal states
-ex. temperature higher or lower than set point (98.6)
3)Adjustment
-Effectors- muscles, glands, internal organs
-ex. sweat to cool the body, shiver to warm the body

Question 20

What is a negative feedback loop?

Answer 20

Used to maintain system at a set point. Output inhibits more output.

Question 21

What is a positive feedback loop?

Answer 21

Used to amplify or accelerate system output. Output of the system increases more output.

Question 22

What is a feed-forward System?

Answer 22

Used to change a set point in preparation for future demands. Inputs from additional sensors or control systems to predict future needs. May link several negative/positive feedback loops together. Can dynamically adjust response without lag or delay.

Question 23

Examples of Negative Feed Back Loop?

Answer 23

Thermostat: Temp too low->increase heat–>temp goes up–>heat turns off.
When there is enough hormone, stop making the hormone.
Regulation of Blood Pressure

Question 24

What are negative feedback loops used to maintain?

Answer 24

Used to maintain set-points.

Question 25

What are negative feedback widely used in?

Answer 25

basal metabolism, blood pressure, and body temp.

Question 26

What is the con of a negative feedback loop?

Answer 26

There is a delay in response. Sensors detect a deviation from the set point, then effect a response, and the response takes time to restore the set point.

Question 27

What is blood pressure monitored by?

Answer 27

Baroreceptors.( sensitive to stretching of blood vessels and heart chambers.

Question 28

What is blood pressure regulated by?

Answer 28

Changes in cardiac output (heart pumping) and changes in vasoconstriction (blood vessels)

Question 29

What do baroreceptors do when the blood pressure is too high?

Answer 29

Baroreceptors fire more–> cardiac output decreases and blood vessels dilate–>blood pressure decreases.

Question 30

What do baroreceptors do when the blood pressure is too low?

Answer 30

Barorecpetors fire less–>cardiac output increases and blood vessels constrict–>blood pressure increases.

Question 31

What are examples of positive feed back loop?

Answer 31

Blood Clotting/Wound Healing : platelets release clotting factors that attaract more platelets.
Lactation: Breastfeeding increases milk production. Milk supple increases with more breastfeeding.
Childbirth: Oxytocin causes contractions causes the release of oxytocin, increasing the strength of the contractions.

Question 32

When does a positive feedback loop end?

Answer 32

When it reaches a goal state and that triggers the negative feedback to stop it. For example, the baby is born, wound is healed. Turn off positive feedback loop.

Question 33

What are examples of feed-forward system?

Answer 33

Heart rate and blood pressure increase before excercise
Saliva and gastric acid production before food is eaten
Increase energy/alterness during the day, decrease at night (For sleep)