A&P LEC Chapter 3 HW

Which of the following is NOT one of the three major components of animal cells? -plasma membrane -ECF -cytoplasm -nucleus

-ECF (explanation: The ECF, or extracellular fluid, is the fluid that fills the space outside cells, so it is not a component of cells.)

Which statement regarding the smooth endoplasmic reticulum (SER) is false? -The SER detoxifies drugs and harmful substances ingested by and produced in the body. -The SER manufactures proteins for export from the cell. -The SER synthesizes the majority of the lipid components of the plasma membrane. -The SER stores calcium ions.

-The SER manufactures proteins for export from the cell.

Which of the following is not a major function of proteins in the cell membrane? -anchoring cells to other structures -acting as receptors -forming channels -forming the entire glycocalyx

-forming the entire glycocalyx (The glycocalyx is composed mostly of carbohydrates.)

Which of the following choices lists a function or functions of this organelle? (golgi apparatus) -digest nutrients, all organelles, and pathogens -modify, sort, and package ---proteins and lipids -detoxify drugs and harmful substances -synthesize proteins

-modify, sort, and package proteins and lipids (The Golgi apparatus processes proteins and lipids coming from the ER and packages them in vesicles bound for different destinations either within or outside the cell.)

Place the following steps of endomembrane system function in the correct order. 1. Golgi apparatus receives transport vesicles from the RER. 2. Ribosomes on the RER synthesize proteins. 3. Proteins are packaged into transport vesicles 4. Modified proteins may be secreted from the cell by exocytosis. 5. Proteins are modified by the Golgi apparatus.

2, 3, 1, 5, 4

Whats the function of this membrane protein?

A receptor is a membrane protein that binds to a chemical messenger called a ligand and allows for cell-cell communication.

Which of the following membrane components is important mainly for cell recognition? -cholesterol -phospholipids -proteins -glycoproteins

Glycoproteins (explanation: glycoproteins and glycolipids are important for cell-cell recognition)

Which of the following is NOT one of the three major components of a typical eukaryotic cell? -cytoplasm -plasma membrane -nucleus -ribosome

Ribosomes (explanation:Ribosomes are organelles and they are located within one of the major components of the cell)

Which of the following best describes secondary active transport? -Secondary active transport occurs when the movement of one substance is coupled with the passive transport of a second substance. -Secondary active transport involves the movement of a substance into a cell through a protein channel with its concentration gradient. -Secondary active transport involves the movement of a substance into a cell with its concentration gradient. -Secondary active transport involves the movement of water by osmosis into a cell.

Secondary active transport occurs when the movement of one substance is coupled with the passive transport of a second substance.

Which of the following describes the fluid mosaic model of the plasma membrane structure? -Phospholipids consist of a polar head and a nonpolar tail made of three fatty acid chains. -The phospholipid bilayer is embedded with associated proteins, cholesterol and sugars and has a dynamic arrangement. -The plasma membrane is composed of two layers of proteins embedded with lipids. -The lipid bilayer is solid at body temperature, thus protecting the cell

The phospholipid bilayer is embedded with associated proteins, cholesterol and sugars and has a dynamic arrangement.

Predict what will happen to a patient's red blood cells if you give the patient an IV of pure water. -They will shrink. -They will remain unchanged. -Their number will increase. -They will burst.

They will burst (The patient's RBCs will swell and burst if placed in pure water, because water is hypotonic.)

Which of following is NOT one of the functions of the plasma membrane proteins? -act as channels -act as receptors -act as transport vesicles -act as enzymes

act as transport vesicles (explanation: vesicles are small sacs formed from phospholipid bilayer, not proteins)

The Na+/K+ pump transports three sodium ions out of the cell for every two potassium ions moved into the cell. This is an example of:

an antiport pump

What is NOT a function of the plasma membrane? What is NOT a function of the plasma membrane? -isolate the cell from its surroundings -structural support -catalyze macromolecules into subunits -communication with other cells

catalyze macromolecules into subunits

A white blood cell engulfs a bacterium through a process called: -endocytosis. -exocytosis. -primary active transport. -facilitated diffusion.

endocytosis

Which of the following is used to export large molecules from the cell? Which of the following is used to export large molecules from the cell? -endocytosis -exocytosis -pinocytosis -phagocytosis

exocytosis (Exocytosis is a type of vesicular active transport that exports large molecules from the cell.)

To make a protein, DNA first is replicated into RNA, and then RNA is transcribed into amino acids. True False

false

A cell is placed into a 3% dextrose solution. At that concentration, the solution is isotonic to the cell. If the concentration of dextrose in the solution is increased to 5%, the cell is now in a(n): -isotonic solution. -less concentrated solution. -hypertonic solution. -hypotonic solution.

hypertonic solution

cellular swelling is likely to occur when blood cells are immersed in: -hypertonic solutions -isotonic solutions -hypotonic solutions -more concentrated solutions

hypotonic solutions

Which of the following acts as the digestive system of the cell, breaking down materials? -ribosome -lysosome -endoplasmic reticulum -nucleus

lysosome

Muscle cells require an abundant amount of ATP to function. Therefore, muscle cells have numerous: -ribosomes -peroxisomes -mitochondria -lysosomes

mitochondria

Within the nucleus, where does ribosome assembly occur? -centromere -nucleoplasm -nucleolus -nuclear pore

nucleolus

Most of a cell's DNA is located in its: -Golgi apparatus. -lysosomes. -ribosomes. -nucleus.

nucleus

Where does transcription of DNA into RNA occur? -mitochondrion -nucleus -Golgi apparatus -peroxisome

nucleus

Molecular machines that perform specific functions for the cell are: -cytosol -the plasma membrane -organelles -the cytoskeleton

organelles

Aquaporins may be employed during; -endocytosis -simple diffusion -osmosis active transport

osmosis

What part of a cell membrane is usually in contact with the interstitial fluid? -cholesterol -hydrophobic molecules -fatty acid tails -phosphate heads of phospholipids

phosphate heads of phospholipids (explanation: The phosphate heads of the phospholipids are polar, so they are attracted to the polar water molecules.)

Which of the following is the main component of the cell membrane? -carbohydrates -water -cholesterol -phospholipids

phospholipids (explanation: Although phospholipids have a polar head, the long fatty acid tails are nonpolar, making the membrane mostly nonpolar.)

Which of the following requires ATP? - simple diffusion -facilitated diffusion -primary active transport -osmosis

primary active transport (During primary active transport, a protein "pumps" a solute against its concentration gradient using energy from ATP.)

What is NOT a function of the peroxisome? -protein synthesis -oxidize toxic substances -break down fatty acids -synthesize certain phospholipids

protein synthesis

Where does protein synthesis occur? -peroxisomes -mitochondria -lysosomes -ribosomes

ribosomes

Which of the following organelles synthesizes proteins? -smooth endoplasmic reticulum -ribosome -peroxisome -Golgi apparatus

ribosomes (ribosomes function in protein synthesis)

Cholesterol in the plasma membrane _______________________. - is important for cell-cell recognition -stabilizes the structure of the plasma membrane when the temperature changes -functions as an enzyme to speed up chemical reactions -is the main component of the lipid bilayer

stabilizes the structure of the plasma membrane when the temperature changes (explanation: This is critical because the plasma membrane must maintain a certain state of fluidity in order to function)

What are the two steps of protein synthesis that produce a protein from a gene? -replication and transcripton -mitosis and cytokinesis -transcription and translation -replication and translation

transcription and translation

Solution A and solution B are separated by a semipermeable membrane, which is permeable to NaCl and water. Solution A contains 10% NaCl, and solution B contains 2% NaCl. By osmosis, __________. -NaCl will move from solution A to solution B -water will move from solution A to solution B -water will move from solution B to solution A -NaCl will move from solution B to solution A

water will move from solution B to solution A (Water will move from a solution with a lower solute concentration to one with a higher solute concentration)