Homeostasis

Question 1

What is a sensor?

Answer 1

detects difference in the system

Question 2

What is a integrator(co coordinator)?

Answer 2

part that detects and manages the response

Question 3

What is a feedback loop?

Answer 3

any system in which part of an output of the system is connected back into one of its inputs

Question 4

What is a negative feedback loop?

Answer 4

a change in a given direction cause change in the opposite direction; restoring the original condition

Question 5

What is an effector(regulator)?

Answer 5

part that effects a change

Question 6

What is a positive feedback loop?

Answer 6

a system which is designed to amplify a small effect (i.e ripening fruit)

Question 7

What is an endotherm?

Answer 7

using physiological mechanism to create thermal energy

Question 8

What is a ectotherm?

Answer 8

using their environment to harness thermal energy

Question 9

What happens when the body temperature is too high?

Answer 9

Carotid artery (sensor) senses the blood temperature and sends a signal to the hypothalamus (integrator) and that switches on a hormone that simulates cooling
Skin vessels dilute, so more blood flows through the skin to lose heat (effector)
sweat glands initiate sweating and cools down the skin (effector)
Body temp decreases (result)

Question 10

What happens when the body temperature is too low?

Answer 10

Carotid artery (sensor) senses when the blood temp is too low and signals the hypothalamus (integrator) to switch on the heating
this causes blood vessels to contract to preserve heat (effector)
skeletal muscles contract and cause shivering to create thermal energy (effector)
body temp increases (result)

Question 11

What do hormones do?

Answer 11

chemicals released in one part of the body that affect cells in other parts of the body

Question 12

Types of Hormones?

Answer 12

Lipid derived i.e steroids; cholesterol, estrogen
Amino acid derived i.e trp
Peptide i.e proteins

Question 13

Difference between nervous system and endocrine system?

Answer 13

Nervous system; brain and spinal cord - very fast, electrical impulses, reflexes like blinking
Endocrine system; glands and organs - can be slow, chemical message, response is widespread, growth; development of reproductive system

Question 14

how do lipids and steroids enter the system?

Answer 14

hormones diffuse into the blood and it enters the target cells. hormone binds to the receptor(sensing component), hormone receptor diffuses into the nucleus and activates a gene where mRNA is transcribed and new protein is made, protein leaves the cell

Question 15

how do protein hormones work?

Answer 15

hormones enter the endocrine cell, it diffuses into the blood, hormone binds to the receptor on cell surface, signal transduction where the hormone receptor complex causes ATP to cAMP–cAMP activates existing enzyme/protein and the activated protein leaves the cell

Question 16

Proteins get broken down into?

Answer 16

C, H, O, N
Nh2 is toxic and the wastes are combined with Co2 to make UREA

Question 17

What do nephrons do

Answer 17

excretes waste and osmoregulation

Question 18

What are the components of the nephron?

Answer 18

proximal convoluted tubule
bowman’s capsule
glomerulus
loop of henle
distal convoluted tubule
vassa recta
collecting duct

Question 19

how does the loop of Henle works?

Answer 19

descending: water leaves, and salt stays inside so the inner medula id high in solute so water osmoses into medula, and the solute concentration of filtrate increases

ascending: permeable to salt, not permeable to water; NaCl diffuses into peritubular blood

Question 20

Distal Conconvoluted Tubule

Answer 20

site of aldosterone action and antidiuretic hormone; NaCl pumps cause more reabsorption, and H+ pumps cause there to be reabsorption of ions

Question 21

Collecting Duct

Answer 21

Not permeable to salt, but is to water…can be influenced by ADH

Question 22

ADH (Anti diurectic hormone)

Answer 22

when there is above 300 mos/L, it is released into the blood; increases permeability to water, making water be reabsorbed, less urine

Question 23

Angiotensin ii and aldosterone

Answer 23

angiotensin is the active form of renin, and increases Na and H2o retention in the body
it helps release aldosterone; balance of water and salts in the kidney by keeping sodium in and releasing potassium from the body
and stimulates the release of ADH

Question 24

Dendrites

Answer 24

branched extension of a neuron to help receive signals from other neurons

Question 25

Axon hillock

Answer 25

cone shaped base of the axon, where the all the information from the dendrites are stored into

Question 26

Synapse

Answer 26

the end of the neuron; branched part, where it passes the signal to another neuron w/ the synaptic cleft

Question 27

neurotransmitters

Answer 27

chemical messengers that pass information

Question 28

sensory neurons

Answer 28

transmit stimuli from eyes and other sensors; information is sent to the brain where interneurons can integrate the information

Question 29

motor neurons

Answer 29

transmits signals to the muscle cells causing them to contract; central nervous system (CNS) most found in animals the neurons that carry info into and out of the CNS form the peripheral nervous system (PNS) PNS neurons form nerves.

Question 30

Na/K pumps

Answer 30

using the energy of ATP help maintain the K+ and Na+ gradient across the plasma membrane 3 Na+ out 2 K+ in hydrolysis of ATP Na+ is high outside of the cell, positive side, and K+ is high inside of the cell, negative side

Question 31

Deeper dive into the Na/K pump

Answer 31

K+ leak channels , membrane more permeable to K+ ions than Na+ ions the transport is much slower due to the + charge outside of the cell more Na+ ions outside of the neuron that provide a + charge higher concentration of Cl-, as it diffuses in the chemical gradient but moves back due to the attraction to positively charge fluid

Question 32

What is membrane potential?

Answer 32

the difference in electric potential between the interior and the exterior of a biological cell.

Question 33

What are the channels inside the neuron membrane?

Answer 33

Voltage gated ion channels; only opens when the membrane potential reaches a certain value; only allows for 1 specific kind of ion to pass through Voltage gated potassium channels Voltage gated sodium channels

Question 34

The graph; break it down into each step

Answer 34

i) Resting state: Approx -70 mV. no signals transmitted ii) Depolarization: when the cell membrane potential reaches the threshold of -55 mV, the Na+ channel opens up, and Na+ is rushed into the cell-- making the membrane potential more positive as it approaches 0 mV iii) Overshoot: when the cell membrane reaches 30 mV, and it becomes positive; peak of action potential iiii) Repolarization: Na+ channel becomes inactive, stopping Na+ from flowing into the cell, resulting in the K+ channel opening, but it opens and closes slower, and K+ leaves the membrane, making it less positive and more negative. v) Hyperonization: K+ channels are slower to close, so for a brief moment the cell membrane is more negative than the resting state, and then eventually the K+ channels close

Question 35

What is the refractory period?

Answer 35

After the action potential, the temporary inactivation of this Na+ channels cause this to occur.

Question 36

What is conduction?

Answer 36

the point where action potential is initiated(axon hillock) electrical current depolarizes the neighboring region of the axon membrane action potentials only travels in a forward direction towards synaptic terminals the inactive Na+ channels help the action potential from traveling backwards

Question 37

What are threshold values?

Answer 37

there aren't any part signals, its all or nothing if the stimulus is not strong enough, then the neuron is not activated action potential increases with the axon's diameter

Question 38

What does the myelin sheath do?

Answer 38

enables fast conduction of action potentials; made from Schwann cells

Question 39

Name of action potential with myelin sheath and Nodes of Ranvier

Answer 39

Saltatory conduction

Question 40

When glucose is too high, what happens?

Answer 40

The hypothalamus senses (sensor) that, and releases insulin from the Islets or Langerhans (from Pancreas) Integrator:co-ordinator — insulin binds to GLUT (glucose transporters) Effectors:regulators — skeletal muscle and fat are all regulated and receive insulin Both factors aid in the decrease of blood glucose levels (result)

Question 41

In the Pancreas, what is the percentage of cells made?

Answer 41

Approx. all Islet cells are: 80% beta cells - insulin 20%alpha cells - glucagon

Question 42

How does the liver intake glucose?

Answer 42

Insulin takes glucose and turns it into glycogen and when glycogen levels reach 5%, they get turned into fatty acid cells

Question 43

What is Glucose Intake?

Answer 43

It stimulates Insulin Secretion; necessary for energy consumption

Question 44

What are GLUTs?

Answer 44

Glucose transporters They help facilitate glucose into the cells by facilitated diffusion; proteins

Question 45

What happens when blood glucose levels are too low?

Answer 45

Hypothalamus detects this (sensor) and tells the Islet of Langerhans to release alpha cells; Glucagon (integrator) Then the liver converts glycogen into glucose and other macromolecules are turned into glucose (effector) Blood sugar rises(result) Muscle protein are broken down into amino acids that get turned into glucose Fats get turned into lipids then glucose

Question 46

What happens when blood glucose levels are too low?

Answer 46

Hypothalamus detects this (sensor) and tells the Islet of Langerhans to release alpha cells; Glucagon (integrator) Then the liver converts glycogen into glucose and other macromolecules are turned into glucose (effector) Blood sugar rises(result) Muscle protein are broken down into amino acids that get turned into glucose Fats get turned into lipids then glucose

Question 47

What causes appetite?

Answer 47

glucagon in energy metabolism can decrease food intake. glucagon increases everything else; glycolysis, gluconeogenesis, lipolysis, ketogenesis, ureagenesis, hepatic amino acid uptake, food intake, energy expenditure

Question 48

skeletal and adipose tissue - carbohydrates

Answer 48

increase in glucose transport; increased permeability to GLUT stimulates the production of glucose (glycogenesis) decreases the rate of glucose breakdown (glycogenolysis)

Question 49

skeletal and adipose tissue - lipid

Answer 49

decreases the rate of lipolysis(turning fats into glucose) stimulates fatty acid synthesis in tissues increases the uptake of triglycerides from the blood into the adipose tissue and muscle

Question 50

skeletal and adipose tissue - protein

Answer 50

increased the rate of transport of amino acids into the tissues increased the rate of protein synthesis in muscle, adipose tissue, liver and other muscles decreases the rate of protein degration

Question 51

what happens to the body from the lack of insulin?

Answer 51

hyperglycemia - glucose can't get into the cells, and there is damage to eyes and kidneys muscle protein is lost and fats are broken down diabetic ketoacidosis breaks down the fat cells that lead to the production of free fatty acids and ketone bodies-- increasing the risk of a coma and death

Question 52

Type i diabetes

Answer 52

lack of insulin, causes hyperglycemia, beta cells are attacked by the immune system insulin has to be added to the body

Question 53

Type ii diabetes

Answer 53

pancreas has been overworked and desensitized causing the body cells to not react to it eventually the beta cells wear out and no more insulin is made person has to change diet

Question 54

How can diet help control type ii diabetes

Answer 54

consuming less sugar and more complex carbohydrates, foods higher in fiber, bedtime snacks high in protein