Biochemistry

Chromatin was first observed and named by ________.

Chromatin was first observed and named by ________.

Chromatin was first observed and named by ________.
A) Walter Flemming
B) Francis Crick
C) Oswald Avery
D) Friedrich Miescher

mikael   168   2 Replies

mikael

Which of the following accurately describes afferent neurons?

Which of the following accurately describes afferent neurons?

Which of the following accurately describes afferent neurons?
A) The cell body is located in the ventral horn of the spinal cord.
B) They are typically multipolar neurons.
C) They transmit information from the periphery to the CNS.

SalwanJ   168   3 Replies

ch1990

At the resting membrane potential, the membrane is most permeable to ________, which moves ________

At the resting membrane potential, the membrane is most permeable to ________, which moves ________

At the resting membrane potential, the membrane is most permeable to ________, which moves ________ the cell due to its electrochemical gradient.
A) sodium : out of
B) potassium : out of
C) sodium : into
D) chloride : into
E)

SalwanJ   168   3 Replies

ch1990

What is the level of membrane depolarization required to induce the sodium channel's positive feedba

What is the level of membrane depolarization required to induce the sodium channel's positive feedba

What is the level of membrane depolarization required to induce the sodium channel's positive feedback loop called?
A) axon hillock
B) suprathreshold
C) threshold
D) subthreshold
E) axon terminal

SalwanJ   168   3 Replies

ch1990

The chemical synapse is bounded by the ________ neuron, from which neurotransmitters are released ac

The chemical synapse is bounded by the ________ neuron, from which neurotransmitters are released ac

The chemical synapse is bounded by the ________ neuron, from which neurotransmitters are released across the synaptic cleft, to the ________ neuron, where the receptors for that neurotransmitter are located.
A) postsynaptic : presynaptic
B)

SalwanJ   168   3 Replies

ch1990

Epinephrine binds best to which of the following receptor types?

Epinephrine binds best to which of the following receptor types?

Epinephrine binds best to which of the following receptor types?
A) alpha1 adrenergic receptors
B) alpha2 adrenergic receptors
C) alpha3 adrenergic receptors
D) beta1 adrenergic receptors
E) beta2 adrenergic receptors

SalwanJ   168   3 Replies

ch1990

What enzyme catalyzes breakdown of catecholamines in the synaptic cleft only?

What enzyme catalyzes breakdown of catecholamines in the synaptic cleft only?

What enzyme catalyzes breakdown of catecholamines in the synaptic cleft only?
A) monoamine oxidase
B) catechol-O-methyltransferase
C) adenylate cyclase
D) acetylcholinesterase
E) choline acetyl transferase

SalwanJ   168   3 Replies

ch1990

On average, blood pH is approximately:

On average, blood pH is approximately:

On average, blood pH is approximately:
A) 7.1.
B) 7.4.
C) 7.6.
D) 7.8.

Cali Fornia   168   2 Replies

Cali Fornia

The quantity (mass number - atomic number) provides:

The quantity (mass number - atomic number) provides:

The quantity (mass number - atomic number) provides:
A) the number of neutrons in a nucleus
B) the number of electrons in the atom
C) the number of protons in a nucleus
D) the combined number of all the neutrons and all the proton

Neves   168   2 Replies

Neves

Identify which structure contains a primary, secondary or tertiary alcohol in the following ...

Identify which structure contains a primary, secondary or tertiary alcohol in the following ...

Identify which structure contains a primary, secondary or tertiary alcohol in the following structures.

A) ________   B) ________   C) ________

Neves   168   2 Replies

Neves

The polar heads of soap molecules are:

The polar heads of soap molecules are:

The polar heads of soap molecules are:
A) hydrophilic and attracted to water
B) hydrophobic and attracted to water
C) hydrophobic and attracted to oils
D) hydrophilic and attracted to oils

Neves   168   2 Replies

Neves

The isoelectric point of an amino acid is defined as:

The isoelectric point of an amino acid is defined as:

The isoelectric point of an amino acid is defined as:
A) the pH at which the amino acid exits in the zwitterion form
B) the pH at which it exists in the basic form
C) the pH at which it exists in the acidic form
D) the pH equals t

Neves   168   3 Replies

LBD

Which of these carbon sources are best suited for use in biotechnology?

Which of these carbon sources are best suited for use in biotechnology?

Which of these carbon sources are best suited for use in biotechnology? Consider two types of target compounds:
i) biodegradeable plastic
ii) intermediates in pharmaceuticals.

The carbon sources are:  http://imgur.com/a/6

helgibjorns   168   1 Reply

bolbol

A gas has a pressure of 540. torr when the temperature is 127 C. When the temperature changes to 27 ...

A gas has a pressure of 540. torr when the temperature is 127 C. When the temperature changes to 27 ...

A gas has a pressure of 540. torr when the temperature is 127 °C.  When the temperature changes to 27 °C, what is the new pressure, if there is no change in volume or amount of gas?

Kaito Momota   168   2 Replies

Elvis Ruiz

What exactly is a nucleation core?

What exactly is a nucleation core?

Trying to understand axon guidance with WASP proteins and the Arp2/3 complex.  Would be very greatful for an answer!

Burninghot   167   2 Replies

Michael0126

Which of the following is/are incorrect?

Which of the following is/are incorrect?

Which of the following is/are incorrect?
A) tRNAs are extremely stable molecules.
B) Eukaryotic mRNA is highly stable.
C) Bacterial mRNA is not rapidly degraded.
D) All of the above.

mikael   167   2 Replies

mikael

Which of the following is true about transcription?

Which of the following is true about transcription?

Which of the following is true about transcription?
A) A repressor protein activates transcription of a negatively regulated gene.
B) A positively regulated gene can be transcribed only in the absence of active repressor.
C) In the

mikael   167   2 Replies

mikael

Can a receptor act as a signal? Explain your answer.

Can a receptor act as a signal? Explain your answer.

Can a receptor act as a signal? Explain your answer.

arealhero   167   3 Replies

milestone23

The major difference between a cell that responds to a signal and one that does

The major difference between a cell that responds to a signal and one that does

The major difference between a cell that responds to a signal and one that does not is the presence of a
a. DNA sequence that binds to the signal.
b. nearby blood vessel.
c. receptor.
d. second messenger.
e. transduction path

arealhero   167   3 Replies

milestone23

Which of the following chemical messengers is lipophilic and is therefore able to cross the cell mem

Which of the following chemical messengers is lipophilic and is therefore able to cross the cell mem

Which of the following chemical messengers is lipophilic and is therefore able to cross the cell membrane?
A) proteins
B) peptides
C) amines (excluding thyroid hormone)
D) amino acids
E) eicosanoids

SalwanJ   167   3 Replies

ch1990

Which of the following hormones is NOT secreted by the endocrine region of the pancreas?

Which of the following hormones is NOT secreted by the endocrine region of the pancreas?

Which of the following hormones is NOT secreted by the endocrine region of the pancreas?
A) glucagon
B) cholecystokinin
C) insulin
D) pancreatic polypeptide
E) somatostatin

SalwanJ   167   3 Replies

ch1990

Most neurons have a resting membrane potential of

Most neurons have a resting membrane potential of

Most neurons have a resting membrane potential of
A) +100 mV.
B) -5 mV.
C) -70 mV.
D) +30 mV.
E) -55 mV.

SalwanJ   167   3 Replies

ch1990

Which of the following is the correct term for the movement of an electrical charge across a membran

Which of the following is the correct term for the movement of an electrical charge across a membran

Which of the following is the correct term for the movement of an electrical charge across a membrane?
A) resistance
B) current
C) transistor
D) potential difference
E) capacitance

SalwanJ   167   2 Replies

SalwanJ

A change in a cell's membrane potential, such that the inside of the cell becomes more positive, is

A change in a cell's membrane potential, such that the inside of the cell becomes more positive, is

A change in a cell's membrane potential, such that the inside of the cell becomes more positive, is referred to as a ________ whereas if it becomes more negative it is referred to as ________.
A) polarization : depolarization
B) depola

SalwanJ   167   3 Replies

ch1990

Which of the following would increase the likelihood of an action potential being generated in a pos

Which of the following would increase the likelihood of an action potential being generated in a pos

Which of the following would increase the likelihood of an action potential being generated in a postsynaptic cell?
A) opening of chloride channels on a postsynaptic cell with no active transport of chloride ions
B) opening of chloride chan

SalwanJ   167   3 Replies

ch1990

Multiple sclerosis is an autoimmune disease, meaning the body attacks itself.

Multiple sclerosis is an autoimmune disease, meaning the body attacks itself.

Multiple sclerosis is an autoimmune disease, meaning the body attacks itself.
A) True
B) False

SalwanJ   167   3 Replies

venusky

Which of the following ions is not isoelectronic with the noble gas neon?

Which of the following ions is not isoelectronic with the noble gas neon?

Which of the following ions is not isoelectronic with the noble gas neon?
A) O2-
B) F-
C) Al3+
D) S2-

Neves   167   2 Replies

Neves

The Na+-K+ ATPase uses the free energy of ATP hydrolysis in an active transport process to move Na+ ...

The Na+-K+ ATPase uses the free energy of ATP hydrolysis in an active transport process to move Na+ ...

The Na+-K+ ATPase uses the free energy of ATP hydrolysis in an active transport process to move Na+ and K+ across a membrane. What would the rate of nonmediated transport be given that the permeability coefficient for K+ through a human erythrocyte m

3493954   167   1 Reply

Nyntti

Which of the following functions as a “flexible swinging arm” when it ...

Which of the following functions as a “flexible swinging arm” when it ...

Which of the following functions as a “flexible swinging arm” when it transfers the reaction intermediate from one active site to the next?
A)   FAD
B)   NAD+
C)   lipoamide
D)   thiamine pyrophosphate
E)   coenzyme A

jackamus   167   1 Reply

iFISH

Stem-loop structures in RNA resemble the ________ form of double-helical DNA. A

Stem-loop structures in RNA resemble the ________ form of double-helical DNA. A

Stem-loop structures in RNA resemble the ________ form of double-helical DNA.
A) A
B) B
C) Z
D) supercoiled circular

mikael   166   2 Replies

mikael

A first messenger is an extracellular messenger that binds to its receptor on the ________ of the ce

A first messenger is an extracellular messenger that binds to its receptor on the ________ of the ce

A first messenger is an extracellular messenger that binds to its receptor on the ________ of the cell and therefore activates a second messenger system.
A) endoplasmic reticulum
B) G protein
C) outside
D) inside
E) ribosome

SalwanJ   166   2 Replies

SalwanJ

What is the functional unit of the nervous system?

What is the functional unit of the nervous system?

What is the functional unit of the nervous system?
A) glial cells
B) the central nervous system
C) axons
D) neurons
E) the brain

SalwanJ   166   2 Replies

SalwanJ

What portion of the peripheral nervous system transmits information from sensory receptors to the ce

What portion of the peripheral nervous system transmits information from sensory receptors to the ce

What portion of the peripheral nervous system transmits information from sensory receptors to the central nervous system?
A) efferent nervous system
B) somatic nervous system
C) autonomic nervous system
D) afferent nervous system

SalwanJ   166   3 Replies

ch1990

The resting membrane potential is close to the equilibrium potential of which of the following ions?

The resting membrane potential is close to the equilibrium potential of which of the following ions?

The resting membrane potential is close to the equilibrium potential of which of the following ions?
A) sodium (Na to power of ((+)))
B) potassium (K to power of ((+)))
C) chloride (Cl to power of ((-)))
D) calcium (Ca to power of

SalwanJ   166   3 Replies

ch1990

In response to stepping on a nail, the crossed-extensor reflex causes

In response to stepping on a nail, the crossed-extensor reflex causes

In response to stepping on a nail, the crossed-extensor reflex causes
A) flexion of the leg on the side of receptor activation.
B) extension of the leg on the side of receptor activation.
C) flexion of the leg opposite the side of rec

SalwanJ   166   3 Replies

ch1990

Which of the following provides support for development of the blood-brain barrier?

Which of the following provides support for development of the blood-brain barrier?

Which of the following provides support for development of the blood-brain barrier?
A) microglia
B) Schwann cell
C) astrocyte
D) ependymal cell
E) oligodendrocyte

SalwanJ   166   3 Replies

venusky

Where in the cerebral cortex does the awareness of limb positions and muscle tension occur?

Where in the cerebral cortex does the awareness of limb positions and muscle tension occur?

Where in the cerebral cortex does the awareness of limb positions and muscle tension occur?
A) parietal lobe
B) frontal lobe
C) temporal lobe
D) occipital lobe
E) corpus callosum

SalwanJ   166   3 Replies

venusky

What area of the brain connects the left and right sides of the brain?

What area of the brain connects the left and right sides of the brain?

What area of the brain connects the left and right sides of the brain?
A) association fibers
B) astrocytes
C) projection fibers
D) blood-brain barrier
E) corpus callosum

SalwanJ   166   3 Replies

venusky

The monomer of the carbohydrates is:

The monomer of the carbohydrates is:

The monomer of the carbohydrates is:
A) fatty acid.
B) amino acid.
C) nucleotide.
D) monosaccharide.

Cali Fornia   166   1 Reply

BleedingDr

Is a Pipetman more like a serological pipet or a Mohr pipet? Why?

Is a Pipetman more like a serological pipet or a Mohr pipet? Why?

Is a Pipetman more like a serological pipet or a Mohr pipet? Why?
  What will be an ideal response?

sophie0209   166   2 Replies

Jonae Wyche