Midterm Exam 1

Week 7: Tuesday, October 7th

_______ explains how and when life began on Earth

the emergent theory of life

the formation of Earth and the presence of an unstable atmosphere happened around _______

4.5 billion years ago

the presence of a stable hydrosphere happened around _______

4.2 billion years ago

prebiotic chemistry (natural chemical processes and pathways of early Earth) happened around _______

4.2-4.0 billion years ago

Pre RNA world happened around _______

4 billion years ago

RNA world happened around _______

3.8 billion years ago

(LUCA) First DNA/protein life occurred around _______

3.6 billion years ago

the diversification of life happened around _______

3.6 billion years ago-present

from the diversification of life, which 3 organisms emerged?

unicellular microorganisms, multicellular organisms, and organisms that can switch between unicellular and multicellular

multicellular organisms have specialized and interdependent cells because they evolved from _______

single-cell organisms

_______ keeps elements such as nitrogen, oxygen, argon, hydrogen, and helium (also found in Earth’s atmosphere and the universe) balanced in our body

hormone communication

our internal environment is 70% water, and compartmentalized into _______ and _______ fluid

intracellular and extracellular

our extracellular fluid is separated into _______ (in tissue) and _______ (in blood vessels, lymph vessels, and the cerebralspinal cord)

interstitial, inter-tubal

true or false: the external environment is dynamic (unstable) and uncertain

true

_______ is the internal regulation of the body in relation to to the external environment, and necessary for growth, survival, and reproduction

homeostasis

_______ feedback loops bring interval levels back to their baseline

negative

_______ feedback loops push internal levels past their baseline in order to communicate a necessary message

positive

_______ is a chemical messenger that coordinates the activities of diferent cell groups in reponse to environmental changes

hormone

true or false: hormones have specific chemical structures that fit into target cell receptors

true

true or false: one endocrine organ can only control its own function

false. One endocrine organ can control the function of other endocrine organs

true or false: a single hormone can induce multiple biochemical responses in its target cell, or multiple hormones can perform the same function

true

during this type of chemical communication, chemicals are sent out of endocrine glands via endocrine cells/glands

endocrine communication

_______ may become specialized to coordinate cellular activity and maintain homeostasis

endocrine cells

_______ consisits of a mass (parenchyma) of secretory cells, connective tissue, blood vessels, and nerves

encorine glands

true or false: endocrine glands can be within tissues of exocrine glands/organs, transient, or produce one/more than one hormone

true

true or false: every cell in our body can only produce one chemical

false. every cell in our body can produce the same chemicals, but for some this ability is turned off for specialization

during this type of chemical communication, chemicals bind to receptors on cells next to each other

paracrine communication

during this type of chemical communication, chemicals bind to receptors on the surface of the cell that releases them

autocrine communication

during this type of chemical communication, chemicals bind to receptors inside the cell that release them, but they remain inside the cell

intracrine communication

soluble, secreted signaling polypeptides capable of instructing specific cellular responses ina biological environment are called _______

growth factors (GF)

during this type of chemical communication, chemicals are released in the brain adn act on the body

neural communications

neurons release these chemicals into tbe bloodstream, which act on distant target organs

neurohormones

neurons release these chemicals at synapses to communicate directly with neighboring neurons

neurotransmitters

neurons release these chemicals that modify the effect of neurotransmitters

neuromodulators

_______ are used between same-specicies organisms to communicatephe

pheromones

_______ are used between different-species of organisms

allomones

true or false: current hormones evolved from chemicals that served a neurocrine/paracrine function

true

_______ focues on body fluids to diagnose illnesses (blood, yellow bile, black bile, phlegm)

Hippocrates’s humoral hypothesis

_______ found that loss of testes in men and birds led to voice and size changes, and less aggression

Aristotle

_______ observed differences between ductile and ductless glands

Thomas Warton

_______ suggested that thyroid gland secreted substances into blood

Fredrik Ruysch

_______ developed radioimmunoassay to measure hormone levels in blood/body fluids

Rosalyn Yalow

_______ and _______ developed immunometric and biological assays to enable the discovery of nerve and epithelial growth factors

Rita Levi-Montalicini and Stanley Cohen

_______ used transgenic and gene knockout animals to enable precise testing for effects of hormones and receptors

Richard Palmiter

hormones, neurotransmitters, neurohormones, pheromones, and allomones are considered ______ because they dont fit into receptors so they’re modified to work and create new chemicals

ligands

true or false: polar hormones are amino acid based

false. polar hormones are cholesterol based

true or false: non-polar hormones are cholesterol based

false. non-polar hormones are amino acid based

true or false: water soluble hormones are polar and can’t pass through the membrane, so they need extracellular receptors

true

true or false: fat soluble hormones are non-polar and can pass through the membrane, so they need intracellular receptors

true

enzymes alter the shape of _______ to create hormones

precursors

the precursor for epinephrine, norepinephrine, doapmine, triiodothyronine, and thyroxine is _______. they are _______ or ________ soluble

tyrosine. fat or water

the precursor for testosterone, estradiol, progesterone, cortisol, aldosterone, and vitamin D is a _______. they are _______ soluble

steroid. fat

the precursor for oxytocin, vasopressin, insulin, and secretin is a _______. they are _______ soluble

peptide/protein. water

_______ is an environmental factor that may alter how chemical signals act on DNA to determine which segment is transcribed

epigenetics

_______ regulates other genes by secreting a regulatory protein

regulatory gene

_______ is affected by the regulatory proteins secreted by the regulatory gene (promotor)

regulatory sequence

_______ help genes be expressed at the right time

transcription factors

the _______ has a signal peptide directing it to the Golgi apparatus, where it’s folded into a _______

pre hormone, signal protein

in the Golgi apparatus, the prehormone is processed into a _______ once enzymes remove the signal protein and carbohyrdates are added

prohormone

the hormone and enzymes are moved into secretory vesicles and excreted out of the cell via _______

exocytosis

true or false: hormones and steroids are stored in secretory vesicles within glands where they're produced

false. only hormones are stored in secretory vesicles within glands where they're produced

what two chemicals are involved in exocytosis to release hormones from vesicles?

ATP and Ca²+

during hormone release, the donor membrane forms vesicles and carries hormones inside and the v-SNARE proteins (coding) tell it where to go. this step is known as ________

budding

during hormone release, the vesicle travels on the cytoskeletal filament via motor proteins (has ATP attached), which pulls it to the right location. this step is known as _______

movement

during hormone release, the vesicle approaches the acceptor membrane so tethering factors and complexes can hold it in place while v-SNAREs on the vesicles and t-SNAREs line up. this step is known as _______

tethering

during hormone release, the vesicle and acceptor membrane fuse so the vesicle can release out of the cell, or in another compartment. this step is known as _______

fusion

_______ are synthesized and immediately absorbed through the membrane

steroid hormones

true or false: hormones circulate in the bloodstream freely in small concentrations, or attached to carrier proteins

true

true or false: hormones bound to carrier proteins can be broken down

false. bound hormones can’t be broken down. separation from carrier proteins is required for hormone effect and destruction

the time it takes for hormone concentration in blood to be reduced by half is the_______

half life

hormones can be broken down by _______, _______, or _______

the liver, kidneys, or muscles (other tissues)

in the liver, a _______ or _______ is added to hormones so they can become more water soluble and leave via urine

sulfate group or acid

these receptors are inside the cell; non-polar (fat soluble) hormones bind here

intracellular receptors 

these receptors are on the membrane and always need secondary messengers; polar hormones (water soluble) bind here

transmembrane receptors

This process is involved in transmembrane receptors and converts the hormone message into a cellular response by changing the cell biochemistry

signal transduction 

these receptors are transmembrane and open or close channels (sodium-potassium pump)

ionotropic receptors

true or false: in the ECF, there are a lot of sodium ions, but in the ICF, there are a lot of potassium ions (both cations)

true

true or false: in the ECF, there are a lot of hydrogen phosphate ions (HPO₄^2-), but in the ICF, there are a lot of calcium ions (both anions)

false. in the ECF, there are a lot of calcium ions, but in the ICF, there are a lot of hydrogen phosphate ions (HPO₄^2-)

these receptors can be intracellular or transmembrane (with or without enzymes), and initiate signaling pathways within the cell

metabotropic receptors

these receptors have enzymes in side (guanylyl cyclase, insulin)

intrinsic enzyme transmembrane receptors

these receptors have enzymes attached (g-protein)

enzyme-coupled transmembrane receptors

true or false: receptors are proteins/glycoproteins, located in the membrane, cytosol, or nucleus, and are categorized base don their derived-from gene

true

the _______ is where the hormone binds to the receptor

binding site

the _______ is where the response is created on a receptor

transducing domain

true or false: fat soluble steroids binding to intracellular receptors results in enzyme production/changes in enzyme production rate

false. fat soluble steroids binding to intracellular receptors results in protein production/changes in protein production rate

true or false: adding a phosphate to a steroid hormone activates it

true

intracellular receptors are _______. if they’re separated, they don’t work

dimers

receptor conformation changes stimulates the complex to bind to _______ on DNA, which are specific sequences that stimulate/repress activity of transcription factors

hormone receptor elements (HREs)

true or false: thyroid/vitamin D hormones are permanently attached to HREs on DNA, regardless if the hormone is present.

true

For thyroid/vitamin D hormone receptors, nuclear proteins attach to receptors to prevent DNA damage because _______

ligands are absent

For thyroid/vitamin D hormone receptors, nuclear proteins which with other proteins so silent genes are expressed because _______

ligands are present 

For thyroid/vitamin D hormone receptors, hormones dissociate from the receptor, are inactivated, then diffuse into ECF because_______

hormone levels declined

_______ initiate signaling pathways that changes gene expression or cell bio chemistry

secondary messengers

_______ receptors have single proteins strands and seven stretches of 25 amino acids

G-protein

G-protein subunits are _______, _______, and _______; all bind to and activate ion channels

alpha, beta, and gamma 

G_as proteins stimulate _______ to catalyze ATP → cAMP

adenylyl cyclase

G_ai proteins _______ adenylyl cyclase

inhibit

G_aq stimulates _______

phospholipase C

G_a12 binds to _______ nucleotide exchange factors

guanine

G-protein alpha subunit is GTPase, and catalyzes _______ to _______

guanosine diphosphate (GDP) to guanosine triphosphase (GTP)