BIO 2870 Exam 2

What provides control over skeletal muscle?

Somatic nervous system

Identify the function of the Cisternae terminal

Stores calcium

Myasthenia gravis is a disease resulting from an autoimmune attack on the ACh receptors of the motor end plate. Binding of antibodies to the ACh receptors results in generalized muscle weakness that progresses as more ACh receptors are destroyed. Which of the following medications would help alleviate the muscle weakness?

a drug that binds to and inactivates acetylcholinesterase (neostigmine)

What kind of nervous cells provide support to neurons?

neuroglia

The posterior pituitary gland stores

oxytocin (OT)

The hormone that inhibits osteoblasts is

parathyroid hormone

The _____ is the layer of meninges that is in direct contact with the surface of the brain

pia mater

excessive urine production, which is a characteristic symptom of all forms of diabetes, is known as

polyuria

the endocrine system

relies on the release of chemicals that bind to target cells

After death, rigor mortis lasts until

myofilaments are broken down

Which of the following is ranked from smallest to largest? A) H-band, sarcomere, myofibril, muscle fiber, fascicle, muscle B) Muscle, fascicle, myofibril, muscle fiber, H-band, sarcomere C) Sarcomere, H-band, muscle fiber, myofibril, fascicle, muscle D) Muscle, fascicle, muscle fiber, myofibril, sarcomere, H-band

A) H-band, sarcomere, myofibril, muscle fiber, fascicle, muscle

The pituitary hormone that controls the release of glucocorticoids is

ACTH

Which of the following is one of the steps that ends a contraction?

Acetylcholine is broken down by acetylcholinesterase

which statement is true about the adrenal glands? A) The hormones of the adrenal cortex rely on control by the autonomic nervous system. B) The adrenal cortex is most important in the control of sodium, potassium, and glucose blood levels. C) The adrenal cortex regulates the adrenal medulla. D) The main hormone of the adrenal medulla is norepinephrine. E) The adrenal androgen hormones are found only in males.

B) The adrenal cortex is most important in the control of sodium, potassium and glucose blood levels

Which is NOT a function of skeletal muscles? A)maintain body posture B)contraction of the heart C)maintain body temperature D)produce bone movement

B) contraction of the heart

Which statement regarding the relaxation phase of a muscle twitch is true? A) The action potential sweeps across the sarcomere during this period. B)The phase begins at stimulation and typically lasts about two milliseconds. C) Muscle tension falls to resting levels. D) Tension rises to a peak E) .Cross-bridges are interacting with active sites on actin filaments throughout this period.

C) Muscle tension falls to resting levels

Which type of neuronal pool is when multiple neurons feed into a single neuron?

Convergence ( used in voluntary & involuntary muscle movements)

The pituitary hormone that stimulates the breakdown of store fats and the release of fatty acids into the blood is

GH

Botulism is caused by a bacterial toxin that prevents the release of ACh at the axon terminals. What happens as a result?

Muscles are not capable of contracting

Clusters of rough endoplasmic reticulum and free ribosomes are known as

Nissl bodies

What is the name of the glial cell that produces myelin in the central nervous system?

Olgliodendrocytes

What is the deepest later of the cranial meninges?

Pia mater

Ogliodendrocytes are to CNS as ______ are to PNS

Schwann cells

What is the neurotransmitter that is responsible for triggering contraction of muscle fibers?

acetylcholine (ACh)

Most of then ATP needed by muscle cells is provided through

aerobic metabolism

An important second messenger in hormonal action is

cAMP

Muscle cells

can only contract

Unlike neurons, neuroglia are

capable of cell division

The brain and spinal cord comprise the

central nervous system

What is the correct order of meninges from outside to inside?

dura mater, arachnoid, pia mater

A layer of collagen fibers that surrounds and entire muscle is called

epimysium

Regarding muscle fiber elongation,

gravity may help lengthen a muscle fiber after elongation

What is the name for the stable internal environment that every living organism must maintain to survive?

homeostasis

In the simplest case, endocrine activity may be controlled by changes in the extracellular fluid composition called ______ stimuli

humoral

A stimulus that opens gated potassium ion channels, moving the membrane voltage value below the resting potential value, results in what?

hyper polarization

Hormones from the _______, which travel in the hypophyseal portal vessels, alter the activity of the anterior pituitary.

hypothalamus

Where are the hormones secreted by the posterior pituitary made?

hypothalamus

Saltatory conduction

is faster than conduction on an unmyelinated axon (continuous conduction)

Aldosterone is the principal

mineralocorticoid

Neurons that have two or more dendrites and a single axon extending away from the cell body are

multipolar

What contains delicate network of collagen & elastin fibers through which cerebrospinal fluid circulates?

subarachnoid space

Thyroid hormones are derived from the amino acid

tyrosine