Human Physiology Quiz #1

The term meaning "programmed cell death" is

a. necrosis. b. apoptosis c. oncogenesis d. diuresis e. cytocide answer: b. apoptosis

Arrange the following events in protein secretion in the proper sequence. 1. The polypeptide chain enters the lumen of the endoplasmic reticulum. 2. A secretory vesicle is formed. 3. A transport vesicle is formed. 4. The polypeptide chain enters the lumen of the Golgi complex.

a. 1, 2, 3, 4 b. 1, 3, 2, 4 c. 1, 3, 4, 2 d. 4, 3, 1, 2 e. 3, 1, 4, 2 answer: c. 1, 3, 4, 2

___________ is a protective layer made up of mostly membrane carbohydrates.

a. Epidermis b. Glycocalyx c. Connective tissue d. Focal Adhesion e. Cadherin answer: b. Glycocalyx

Each of the following statements concerning mitochondria is true except one. Identify the exception.

a. The mitochondrial cristae form the inner membrane forming separate compartments. b. The matrix of the mitochondria contains metabolic enzymes involved in energy production. c. The intermembrane space plays an important role in mitochondrial ATP production. d. The mitochondria contain no DNA or RNA. e. The mitochondria produce most of a cell's ATP. answer: d. The mitochondria contain no DNA or RNA.

Every substance that enters or leaves the internal environment of the body must cross an epithelium.

a. True b. False answer: a. True

Which substance is responsible for activating the digestive enzymes inside lysosomes?

a. air b. water c. acid d. enzymes e. base answer: c. acid

Information stored in the nucleus is translated into

a. carbohydrates b. lipids c. proteins d. phospholipids e. None of the answers are correct. answer: c. proteins

The reactions of glycolysis occur in the cell's ___________; the reactions of the citric acid cycle occur in the ____________.

a. cytoplasm, cytoplasm b. mitochondria, mitochondria c. cytoplasm, mitochondria d. mitochondria, cytoplasm answer: c. cytoplasm, mitochondria

Which of the following is NOT a molecule synthesized in the smooth endoplasmic reticulum (SER)?

a. fatty acids b. steroids c. proteins d. lipids e. All are synthesized in the SER. answer: c. proteins

Centrioles

a. function as pipelines to move fluid through the cell. b. direct the movement of DNA during cell division. c. hold the cell's ribosomes in place. d. are white blood cells out of vessels. e. provide shape and stability to a cell answer: b. direct the movement of DNA during cell division.

Cell membranes are said to be ___________ because they allow some substances to pass but not others.

a. hydrophilic b. a physical barrier c. structural d. selectively permeable e. metabolically active answer: d. selectively permeable

Cell membranes are said to be

a. impermeable barrier b. freely permeable barrier c. selectively permeable barrier d. only permeable to water soluble molecules e. None of the answers are correct. answer: c. selectively permeable barrier

Which proteins assist in the movement of vesicles along microtubules?

a. kinesins b. mitochondria c. rough endoplasmic reticulum d. ribosomes e. Golgi complex answer: a. kinesins

Oxytocin is a hormone that is released in response to cervical dilation. It in turn causes more uterine contractions that will further dilate the cervix. Which type of feedback loop does oxytocin trigger?

a. negative feedback b. positive feedback c. local control d. nociceptive feedback answer: b. positive feedback

Homeostasis is the ability of the body to

a. prevent the external environment from changing b. prevent the internal environment from changing c. quickly restore changed conditions to normal d. ignore external stimuli to remain in a state of rest e. prevent excessive blood loss answer: c. quickly restore changed conditions to normal

The addition of a phosphate group to a substrate is called ____________. The enzyme that catalyzes this reaction is referred to as a ____________.

a. proteolysis, phosphatase b. phosphorylation, phosphatase c. proteolysis, kinase d. phosphorylation, kinase answer: d. phosphorylation, kinase

Which of the following consists of a network of intracellular membranes with attached ribosomes?

a. rough endoplasmic reticulum b. smooth endoplasmic reticulum c. mitochondria d. nucleoli e. Golgi apparatus answer: a. rough endoplasmic reticulum

If a cell lacked lysosomes, it would not be able to

a. synthesize lipids b. produce enzymes c. digest cellular wastes and bacteria d. destroy H2O2 e. transport water-soluble molecules answer: c. digest cellular wastes and bacteria

Following post-translational modification, any misfolded protein will be destroyed by

a. ubiquitin b. chaperones c. methylation d. ribonucleases answer: a. ubiquitin

Peroxisomes

a. use an enzyme to destroy H2O2 that is toxic to the cell. b. are a type of lysosome. c. are responsible for the atrophy of unused muscles. d. are sites for synthesis of fatty acids, steroids, and phospholipids. e. All of the answers accurately describe peroxisomes. answer: a. use an enzyme to destroy H2O2 that is toxic to the cell.