bi108 quiz 6

homeostasis

the stability of the internal environment and the mechanisms used to maintain that stability

external cell environment

the internal cellular envrionment is always challenged by the ____________________

1. sensors/receptors provide info

2. control mechanism obtain and process info

3. effectors receive commands

three components of a homeostatic control system

control systems

sense when conditions deviate from 'normal' and initiate physiological mechanisms to correct the error

feedback information

information that is compared to the set point by the sensor

error signal

any difference between the set point and feedback information

effector

tissues/organs that can alter the internal environment

negative feedback

information that returns system to set point

positive feedback

amplifies a response and increases deviation from a set point

at constant levels

how are blood glucose levels maintained?

insulin and glucagon

in the pancreas, there are multiple types of cells that produce diff hormones, ie: _____-

glycogen

in the liver, glucose is stored as

pancreas secretes insulin which reduces blood glucose levels

when glucose levels are high...

pancreas secretes glucagon which breaks down glycogen and increases glucose

when blood glucose levels are too low..

both negative

the increase/decrease of glucose levels are examples of what type of feedback?

the endocrine system

the collection of glands that secrete hormones that control prolonged activities

the circulatory system and affect a distant target

endocrine cells release hormones that travel through ___________

the brain controls the secretion of many hormones

how do the nervous system and endocrine system work together?

1. neurosecretory cells

2. nonneural endocrine cells

two types of endocrine cells

neurosecretory cells

excitable cells that propagate action potentials

CNS; the axon terminals release hormones into the blood

neurosecretory cells have cell bodies in the ____________

nonneural endocrine cells

not excitable; typically stimulated to secrete hormone by other hormones

pituitary gland

secretes hormones that control many other glands

attached to the hypothalamus of the brain (directly attached to CNS)

where is the pituitary gland

1. anterior pituitary

2. posterior pituitary

two parts of the pituitary gland

- growth

- blood pressure

- metabolism

- water balance

- temp regulation

- stress response

what do pituitary glands control?

hypothalamic-pituitary-adrenal (HPA) axis

a major neuroendocrine pathway relevant to the stress response involving the hypothalamus, pituitary gland, and the adrenal cortex

neurohormones

produced and released by neurons in the brain, rather than by the endocrine glands, and delivered to organs and tissues through the bloodstream

tropic hormones

hormones that stimulate other glands to release their hormones

hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and DIRECTLY affect other tissues

neurohormones

what type of hormone stimulates from the hypothalamus to the anterior pituitary

tropic hormones

what type of hormone stimulates from the anterior pituitary to other endocrine glands

hormones

what type of hormone stimulates from other endocrine glands to hormones that stimulate cells/tissues

secretes a neurohormone

in the HPA axis, in response to stress the hypothalamus _________

stimulates the anterior pituitary to release a tropic hormone

in the HPA axis, once the neurohormone is released it ________

travels through the blood to adrenal cortex which secretes the hormones: cortisol and epinephrine

in the HPA axis, once the tropic hormone is released, it __________

respiratory system

A system of organs, functioning in the process of gas exchange between the body and the environment

1. bulk flow: inhaling air into nose and mouth

2. diffusion: oxygen goes into blood stream from small pocket in lungs

3. bulk flow: moving oxygen through blood stream

4. diffusion: oxygen goes into muscle cells

steps of the respiratory system

rate of diffusion is proportional to (surface area)(concentration gradient)(membrane permeability)/ membrane thickness

fick's law

from the body tissues to the lungs

hows does the body remove CO2?

4 polypeptide subunits and each polypeptide surrounds an iron containing heme group that can bind O2 (or CO2)

what is the hemoglobin made of?

1. 5% carried in plasma

2. 20% carried in hemoglobin

3. remainder carried as bicarbonate ions

three mechanisms by which CO2 is transported

red blood cells meaning higher partial pressure in body tissue

the conversion of CO2 to HCO3- lowers the partial pressure of CO2 in _____________

from tissue into blood because we've maximized partial pressure difference between body cell and blood stream

as we lower the pressure of CO2 where will it move?

lower pH, so more acidic

what does more CO2 say about the pH

- increase cellular respiration

- increase production of CO2

- more CO2 means more H+

- chemosensory cells detect this CO2 and H+ and increase breathing rate

when cells need more ATP they..

open circulatory system

what type of circulatory system do arthropods have?

hemolymph

blood and other fluids that slosh around the tissues and organs in an open circulatory system

1. heart (the muscular pump)

2. "tubes": the passageway for blood

3. blood (fluid pumped)

three parts of the closed circulatory system

capillaries

site of exchange between blood and tissue

arteries

move blood away from the heart

veins

return blood to heart

Vasolidation

the enlargement of blood vessels/ relaxes muscles to increase blood supply,

vasoconstriction

Reduces blood flow and heat transfer by decreasing the diameter of superficial blood vessels.

respiratory pigments

proteins that transport oxygen, greatly increase the amount of oxygen that blood can carry

4

how many oxygens does hemoglobin hold?

270 million

how many hemoglobin per red blood cell

oxygenation

when a pigment picks up oxygen: "oxygen loading"

deoxygenation

process of removing or having a lack of oxygen "unloading"

75%

blood returns to lungs ___________ saturated

the pressure of oxygen decreases (due to it being used in cellular respiration).

oxygen held in hemoglobin is released when...

rarely

is hemoglobin ever fully unloaded?

75%

at rest hemoglobin is _________ saturated

more

the lower the partial pressure of oxygen, the _______________ oxygen molecules hemoglobin will release

lungs

where is hemoglobin 100% saturated?

systemic circuit

brings oxygenated blood to body tissues

pulmonary circuit

brings deoxygenated blood to lungs (goes to lungs, picks up CO2, releases CO2, then goes back to heart)

right ventricle --> lungs --> left atrium

what is the order of organs for the pulmonary circuit?

left ventricle --> body --> right atrium

what is the order of organs for the systemic circuit?

right atrium and right ventricle

first, oxygen depleted blood enters the _________ which then flows into _________

pulmonary arteries to the lungs

after deoxygenated blood enters right ventricle, its pumped through the _________________

left atrium and then left ventricle

O2 rich blood in the lungs goes to.....

aorta to the systemic tissues

once o2 rich blood is in the left ventricle it is pumped through ______

1

during exercise, how many oxygen molecules does the hemoglobin hold?

cardiac cycle

cycle of contraction and relaxation o the heart

pacemaker

initiates the contraction (heartbeat)

sinoatrial (SA) node

pacemaker of heart in right atrial wall that rhythemically depolarizes without external stimulus

cardiac muscle cells

electrically coupled (when 1 cell contracts so does its neighbors)

atrioventricular (AV) node

relays the depolarization to the conducting system (modified muscle cells) and then ventricles contract in unison

contractions reach the AV node so the atria contract before the ventricles

what happens when both atria are depolarized?

adrenal glands release epinephrine that increases speed of contractions

how to increase heart rate?

heart rate and blood vessel constriction

what two things can manipulate blood pressure

immune system

A system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response

lymphatic system

Composed of a network of vessels, ducts, nodes, and organs. Provides defense against infection.

lymph

fluid derived from blood (But no red blood cells)

collected from body tissues, filters through lymph nodes, eventually returns to blood

pathway of lymph

Leukocytes

white blood cells that recognize non-self cells and initiate an immune response

innate and adaptive

two types of immune defenses

innate defenses

this type of defense is non-specific and always present

skin, mucus,

examples of innate defenses

yes

do innate defenses respond in the same way to every non self cell?

Phagocytosis

A type of endocytosis in which a cell engulfs large particles or whole cells

phagocyte

A white blood cell that destroys pathogens by engulfing them and breaking them down

digestive enzymes to break down the non-self cell

phagocytes for a vesicle and then bind with a lysosome that contains ___________

1. diversity

2. specificity

3. ability to distinguish self from nonself

4. immunological memory

four keys of adaptive immunity

10 million

how many antigens can humans respond specifically to?

antigen

any particle, cell, or molecule that can trigger an immune response

antibodies

produced by specialized lymphocytes (white blood cells) that recognize an antigen

free antibodies or carried by B-cell

where are antibodies found?

one antigen

each antibody is specific to _______