H O M E O S TA S I S

EOCT QUIZ #6

WHICH PROCESS MOVES WATER MOLECULES ACROSS THE MEMBRANE OF A CELL?

A) diffusion B) endocytosis C) exocytosis D) osmosis

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ACTIVE TRANSPORT OCCURS IN CELLS, FOR EXAMPLE, WHEN THE NA-K PUMP IS AT WORK. ANY PROCESS THAT

INVOLVES ACTIVE TRANSPORT MOST OFTEN INVOLVES THE

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A)movement of molecules without any predictable pattern.

B)movement of molecules from a lower concentration to a higher concentration.

C)movement of molecules from a higher concentration to a lower concentration.

D)movement of molecules from a lower to higher concentration and then back to the point of origin.

HOW WILL THE MOVEMENT OF WATER ACROSS THE CELL MEMBRANE AFFECT THE SIZE OF A CELL IF IT IS MOVED FROM AN 80% SUCROSE SOLUTION TO A 40% SUCROSE SOLUTION?

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A) The cell will reduce in size. B) The cell will increase in size. C) The cell will remain unaffected.

D) The cell will increase in size first and then reduce in size.

WHEN A RAW, SHELL-LESS EGG WAS PLACED IN SUGAR SOLUTION, THE EGG SHRANK. THE EGG WAS BROUGHT BACK

TO ITS ORIGINAL SIZE BY PLACING IT IN WATER. WHICH PROCESS DOES THE EXPERIMENT DEMONSTRATE?

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A) osmosisB) endocytosis C) exocytosis D) diffusion

WHICH PROCESS DESCRIBES THE ATP-REQUIRING MOVEMENT OF EXTREMELY LARGE SUBSTANCES OUT OF A CELL IN POCKETS CALLED VESICLES?

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A) exocytosisB) endocytosis C) Passive

transportD) diffusion

LARGE MOLECULES, LIKE GLUCOSE, ENTER CELLS BY

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A) diffusion through the cell membrane.

B)diffusion through protein channels in the cell membrane.

C)endocytosis, when the cell engulfs the particles with pseudopods.

D)active transport, when the cell pumps large molecules in through the membrane.

THE GRAPH ILLUSTRATES THE ACTIVITY LEVEL OF THREE COMMON DIGESTIVE ENZYMES, ACROSS A RANGE OF PH VALUES. WHICH ENZYME IS LIKELY TO BE ACTIVE IN THE

ACIDIC ENVIRONMENT OF THE STOMACH?

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A) pepsin B) trypsin C) amylase D) pepsin and trypsin

SALIVARY AMYLASE IS AN ENZYME FOUND IN THE MOUTH. IT BREAKS DOWN STARCH INTO SUGARS.

WHY WILL SALIVARY AMYLASE NOT BREAK DOWN PROTEINS?

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A) he enzyme is the wrong substrate for proteins.

B) Only sugars have the correct shape to activate the enzyme.

C) Proteins will not fit into the active site of the amylase enzyme.

D) Proteins do not have the proper active site for the enzyme to work on them.

WHAT WILL BE THE EFFECT OF PLACING A PLANT CELL IN A HYPOTONIC SOLUTION?

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A) The cell will dissolveB) The cell will shrink in size.

C) The cell will remain unaffected.

D) The cell will expand and may burst.

WHICH CELL STRUCTURE IS THE GATEKEEPER, CONTROLLING WHAT GOES IN

AND OUT OF THE CELL?

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A) C - NucleusB) E - VacuoleC) A – Cell Membrane D) B – Endoplasmic Reticulum

KEY

1. D2. B3. B4. A5. A6. B7. A8. C9. D10.C