Practice Exam B Flashcards
Which of the following processes explains why an individual that has suffered a broken bone and is immobilized for an extended period of time experiences bone mass loss?` A. Demineralization B. Muscle atrophy C. Ossification D.Kyphosis
A. Demineralization - The decrease in mechanical stress that results from immobility can lead to demineralization, as mechanical stress induces bone growth.
Ossification - This is the process of transforming cartilage into bone tissue, therefore increasing bone mass.
Kyphosis - This refers to curvature of the spine, not loss of bone mass due to immobility.
Which of the following statements correctly matches a body system with its function?
A. The digestive system facilitates absorption of substances into the bloodstream.
B. The respiratory system transports oxygenated blood throughout the lungs and body.
C. The excretory system prevents harmful substances from entering the body.
D. The endocrine system transports hormones from place to place within the body.
A. The digestive system includes the intestines, where nutrients are absorbed into the bloodstream.
Which of the following glands produces melatonin, the hormone that regulates sleep? A. Thyroid B. Hypothalamus C. Pituitary D. Pineal
D. The pineal gland produces melatonin.
The lungs are covered by a membrane called the A. pericardium B. periosteum C. symphysis D. pleura
D. The visceral and parietal pleura cover the lungs.
The pericardium is the tissue covering the heart.
The periosteum is the tissue covering bones.
The symphysis is a cartilaginous joint between two bones.
Which of the following glands is found on top of the kidneys? A. Thyroid B. Pituitary C. Adrenal D. Pancreas
C. Adrenal
The thyroid is located in the front of the neck.
The pituitary is located at the base of the brain.
The pancreas is located in the top of the abdomen behind the stomach.
When an enzyme is degraded into its monomeric structural units, the monomers will be A. monosaccharides. B. fatty acids. C. nucleotides. D. amino acids.
D. Amino acids are constituents of proteins, and enzymes are proteins.
Monosaccharides are constituents of carbohydrates.
Fatty acids are constituents of lipids.
Nucleotides are constituents of nucleic acids.
Skeletal muscle contraction is stimulated by the neurotransmitter \_\_\_\_\_\_\_\_, which is released by nerves at the neuromuscular junction. A. acetylcholine B. nitric oxide C. dopamine D. glycine
A. Acetylcholine is the neurotransmitter released by the autonomic nervous system that causes skeletal muscles to contract.
Which of the following illustrates a negative feedback mechanism that occurs in the human body?
A. The release of insulin from the pancreas in response to an increase in blood-sugar levels
B. The release of glucagon from the pancreas in response to an increase in blood-sugar levels
C. The release of oxytocin resulting in uterine contractions as childbirth is underway
D. Chemical reactions that result in coagulation due to fibrin being released
A. As blood-sugar levels increase, insulin is released in an effort to return blood-sugar levels back to initial levels.
Positive feedback loops amplify changes; this tends to move a system away from its equilibrium state. Negative feedbacks tend to dampen changes; this tends to make it more stable
Which of the following conditions is related to an abnormality in the function of red blood cells? A. Arrhythmia B. Anemia C. Hypertension D. Leukemia
B. Anemia results when hemoglobin in red blood cells does not transport enough oxygen.
A wrong - Arrhythmia results in heart rhythm problems and is not related to red blood cells.
Which of the following explains why gases are termed “compressible” and liquids are not?
A. Particles have fixed volume and are able to occupy the container in which they are contained.
B. Particles do not have much empty space between them, thus making them rigid.
C. Particles have a large amount of empty space between them.
D. Particles are held closely together by intermolecular forces.
C. This correctly describes the composition of a gas and its ability to compress; particles in liquids and solids do not have a large amount of empty space between them.
Which of the following results from the release of the neurotransmitter dopamine into the nerve synapse?
A. The presynaptic neuron fires an action potential.
B. Dopamine binds to receptor proteins on the membrane of the postsynaptic cell.
C. Dopamine enters the cytoplasm of the postsynaptic cell.
D. Dopamine causes the postsynaptic nerve cell to contract.
B. When dopamine enters the synapse, it binds to receptor proteins of the postsynaptic cell, causing a response in the cell. Neurotransmitters are usually polar and act by binding receptors on the postsynaptic neuron.
A first-degree burn involves which of the following layers of skin?
A. Epidermis only
B. Epidermis and part of the dermis
C. Epidermis and all of the dermis
D. Epidermis, dermis, and some muscle and bone
A. A first-degree burn is painful and involves only the epidermis. A sunburn is a !rst-degree burn.
The cause of cell di!erentiation is that different cells
A. contain different DNA.
B. have different chromosomes.
C. contain similar protein information.
D. express alternate genetic information.
D. Different cell types express different subsets of genes.
A blood sample taken from a patient fighting an infection is expected to show A. reduced white blood cell count. B. elevated white blood cell count. C. elevated red blood cell count. D. reduced red blood cell count.
B. White blood cells increase in number when fighting infection.
What is the role of the urethra? A. To transport urine out of the body B. To transport the egg to the uterus C. To connect the kidneys to the bladder D. To connect the uterus to the outside of the body
A. The urethra connects the bladder to the opening of the body and allows the urine to leave.
