A cell is a complex system. Like most systems, a cell contains a boundary that separates things that are inside the system from those that are outside of the system. Which part of the cell functions as a system boundary?
Responses
A cytoplasmcytoplasm
B membranemembrane
C nucleusnucleus
D ribosome
B membrane
Nutrients enter a cell ______ the concentration gradient by the process of _______.
Responses
A with; diffusionwith; diffusion
B against; osmosisagainst; osmosis
C against; diffusionagainst; diffusion
D with; endocytosis
A with; diffusion
Describe the movement of molecules in the illustration.
Responses
A Molecules are moving from a lower concentration to a higher concentration.Molecules are moving from a lower concentration to a higher concentration.
B Molecules are moving from a higher concentration to a lower concentration.Molecules are moving from a higher concentration to a lower concentration.
C Molecules are moving from a higher concentration to a lower concentration and then from a lower to higher concentration.Molecules are moving from a higher concentration to a lower concentration and then from a lower to higher concentration.
D Molecules are moving from a lower concentration to a higher concentration and then from a higher concentration to a lower concentration.
B Molecules are moving from a higher concentration to a lower concentration.
To study osmosis, a student placed a thin potato slice in a salt solution. The slice became soft and shriveled. Then, he placed the shriveled slice in water. The slice regained its original shape. Based on the observations, which of these statements is correct?
Responses
A The slice regained its shape because salt moved into the potato.The slice regained its shape because salt moved into the potato.
B The potato slice shriveled because water moved from the salt solution into the slice.The potato slice shriveled because water moved from the salt solution into the slice.
C The potato slice shriveled because water moved out of the slice into the salt solution.The potato slice shriveled because water moved out of the slice into the salt solution.
D The slice regained its shape because the concentration of salt inside and outside the slice became equal.The slice regained its shape because the concentration of salt inside and outside the slice became equal.
C The potato slice shriveled because water moved out of the slice into the salt solution.
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Question
Egg Osmosis
Solution (to remove shell) Egg mass (g) Initial Egg mass (g) after 24 hrs Student Observations
Vinegar (Egg 1) 45 85 Shell gone; egg seemed swollen and larger
Vinegar (Egg 2) 45 85 Shell gone; egg seemed swollen and larger
Vinegar (Egg 3) 45 85 Shell gone; egg seemed swollen and larger
Experimental Solution Egg mass (g) Initial Egg mass (g) after 24 hrs Student Observations
10% Salt Water Solution (Egg 1) 85 85 No change in egg appearance or size
Kayro Syrup (Egg 2) 85 31 Egg was wrinkled and shriveled; much smaller
Distilled Water (Egg 3) 85 105 Egg was larger in size; swollen and tight
Introduction: Students performed an experiment using eggs to observe the effect of osmosis on cells. The egg represented a typical cell. Before beginning the experiment, students soaked the raw eggs overnight in vinegar to remove the shells. What they had in hand, then, was actually a raw, shell-less egg.
Procedure: Day 1 – Students found the mass in grams of their shelled eggs, recording the mass in the data table. The eggs were placed in a beaker and covered with 200 mL vinegar to remove the shells.
Day 2 – The eggs were removed from the vinegar. Visual observations were recorded. The shell-less eggs were wiped dry, massed, and the mass was recorded in the data table. The eggs were placed in a clean beaker and covered with a 10% saltwater solution.
Day 3 – The eggs were removed from the saltwater and visual observations were made and recorded. The eggs were wiped dry , massed, and the mass was recorded. The eggs were placed in a clean beaker and covered with sugar (Kayro) syrup.
Day 4 – The eggs were removed from the syrup and visual observations were made and recorded. The eggs were carefully wiped with a damp cloth, massed, and the mass was recorded. The eggs were placed in a clean beaker and covered with colored (red, green, or blue) distilled water.
Day 5 – The eggs were removed from the water and visual observations were made and recorded. The eggs were dried, massed, and the mass was recorded. Students organized their data and made a bar graph comparing how the solutions affected their egg's (cell’s) mass. Data: One student group’s data is recorded here.
Based on the data in the table, the students can conclude that which substance is hypertonic?
Responses
A vinegarvinegar
B salt watersalt water
C Kayro syrupKayro syrup
D distilled water
B salt water
Plant and animal cells differ in a variety of ways. Notice when you compare the model cells, plant cells contain chloroplasts and animal cells do not. What is the function of this organelle found in plant cells?
Responses
A It is the site of photosynthesis, where glucose is produced.It is the site of photosynthesis, where glucose is produced.
B It is the site of cellular respiration, where cellular energy is produced.It is the site of cellular respiration, where cellular energy is produced.
C It is the site of cellular digestion; glucose is broken down to produce energy.It is the site of cellular digestion; glucose is broken down to produce energy.
D It is the site of protein synthesis; amino acids are joined together to make proteins.
A It is the site of photosynthesis, where glucose is produced.
Sometimes when plants are under water stress, they wilt. Animals do not wilt! Review the plant cell structure. What analogy based on the plant cell structure explains wilting?
Responses
A The chloroplast are like a factory. When the plant is water stressed, the chloroplast stops producing energy and the plant wilts.The chloroplast are like a factory. When the plant is water stressed, the chloroplast stops producing energy and the plant wilts.
B The cell wall is like a cardboard box. When the plant is water stressed, the cell wall folds, like someone crushing the cardboard box.The cell wall is like a cardboard box. When the plant is water stressed, the cell wall folds, like someone crushing the cardboard box.
C The large vacuole is like a water-filled balloon. When the plant is water stressed, the water leaves the vacuole and the cells shrinks.The large vacuole is like a water-filled balloon. When the plant is water stressed, the water leaves the vacuole and the cells shrinks.
D The plasma membrane is like the drain in your sink. When the plant is water stressed, the plasma membrane stops water from
C The large vacuole is like a water-filled balloon. When the plant is water stressed, the water leaves the vacuole and the cells shrink.
The picture shows the active transport of ions by the sodium-potassium pump.
How is diffusion different from this process?
Responses
A Diffusion takes place due to osmotic pressure.Diffusion takes place due to osmotic pressure.
B Diffusion requires cellular energy for the transfer of molecules.Diffusion requires cellular energy for the transfer of molecules.
C Diffusion requires protein channels as a passage-way for particles.Diffusion requires protein channels as a passage-way for particles.
D Diffusion transfers particles from an area of high to low concentration.
D Diffusion transfers particles from an area of high to low concentration.
As the messenger RNA is translated by the ribosome, the growing polypeptide chain is inserted into the membrane of the _____________ before being sent to its final destination.
Responses
A cellcell
B ribosomeribosome
C rough ERrough ER
D mitochondria
C rough ER
Which picture in the diagram would be classified as a prokaryote?
Responses
A AA
B BB
C CC
D D
D D
What characteristic makes the answer for Question #1 a prokaryote?
Responses
A no membrane-bound organellesno membrane-bound organelles
B contains a cell (plasma) membranecontains a cell (plasma) membrane
C has a nucleus to hold the cell's DNAhas a nucleus to hold the cell's DNA
D has the ability to move by flagella or ciliahas the ability to move by flagella or cilia
A no membrane-bound organelles
Review the image of the cell. What type of cell is this? Provide an explanation for your answer.
Responses
A It is a eukaryotic animal cell. It contains organelles excluding chloroplasts.It is a eukaryotic animal cell. It contains organelles excluding chloroplasts.
B It is a prokaryotic animal cell. It is rounded, has organelles and DNA in a nucleus.It is a prokaryotic animal cell. It is rounded, has organelles and DNA in a nucleus.
C It is a prokaryotic cell. It does not contain cellular organelles including a nucleus.It is a prokaryotic cell. It does not contain cellular organelles including a nucleus.
D It is a eukaryotic plant cell. it contains organelles and the shape indicates a plant cell.
A It is a eukaryotic animal cell. It contains organelles excluding chloroplasts.
The arrow is pointing to what structure?
Responses
A ribosomeribosome
B centriolecentriole
C nucleic acidnucleic acid
D mitochondria
A ribosome
Cells are able to remove large amounts of material using
Responses
A ectocytosis.ectocytosis.
B exocytosis.exocytosis.
C phagocytosis.phagocytosis.
D pinocytosis.
C phagocytosis.
A cell with chloroplasts and a cell wall made of cellulose would likely belong to a(n)
Responses
A frog from Kingdom Animalia.frog from Kingdom Animalia.
B mushroom from Kingdom Fungi.mushroom from Kingdom Fungi.
C oak tree from Kingdom Plantae.oak tree from Kingdom Plantae.
D paramecium from Kingdom Protista.
C oak tree from Kingdom Plantae.
One of the differences between a plant and animal cell can be found surrounding the outer cell structure of the plant cell. It provides structure and support to the plant cell. What is this structure?
Responses
A cell wallcell wall
B cytoplasmcytoplasm
C chlorplastchlorplast
D mitochondria