Biology Mid-Term: Cell Function and Structure
Which statement supports the cell theory as it is stated today?
New cells are produced by division of existing cells
The part of the cell that is most important in maintaining homeostasis with the cell's environment is the...
Plasma membrane
The cell membrane is usually selectively permeable. If the cell membrane is affected by a certain toxin, it becomes impermeable (not-permeable) and the cell dies. Provide 2 reasons that the cell would die.
The cell would if nutrients were not able to pass the cell would die from not having energy to live. The cell would not be able to get rid of the waste which could cause it to die as well.
Human nerve and muscle cells contain many more mitochondria than skin cells. Why do some cells more mitochondria than others?
The cells use more energy
Which of the following statements best identifies the 2 cells shown below?
Cell X is a prokaryotic cell and cell Y is a eukaryotic cell.
What is the primary difference between diffusion and osmosis?
Diffusion is the movement of any substance from high to low concentration, while osmosis is the movement of water from high to low concentration
A student is asked to draw four cells. Which drawing is a representation of a prokaryotic cell?
Drawing C
A single prokaryotic cell can divide several times in an hour. Few eukaryotic cells can divide as quickly. Which of the following statements best explains this difference?
Eukaryotic cells are more structurally complex than prokaryotic cells.
Materials move through the cell membrane by active transport and passive transport. Explain how you know which diagram illustrates active transport.
I know that diagram d illustrates active transport because it is showing channel proteins. The molecule is transported through the channel using energy and the model shows the channel protein. It transports molecules through the membrane using energy.
If the students were to create a salt solution that was isotonic to the potatoes, what concentration should they make? Explain your reasoning.
If there was a isotonic solution the mass of the potatoes would stay the same and the change would be zero. The concentration would be 0%.
The rough endoplasmic reticulum and Golgi apparatus work together in eukaryotic cells. What is one way that the rough endoplasmic reticulum assists the Golgi apparatus?
It transports and packages new protein molecules into vesicles
Both active transport and facilitated diffusion make use of molecules that change shape and move substances through the membrane. These molecules are made of...
Proteins
The diagram models the time-lapse movement of particles across a cell membrane. The particles have characteristics that allow them to pass freely across the membrane. Select all of the statements that describe the particles or their movement based on the time lapse diagram.
The movement across the membrane does not require added energy. The particles crossing the membrane do not have a charge. The particles crossing the membrane could be water or oxygen gas.
Which of the solutions were hypotonic to the potato slices? Explain how you know.
The solutions that were hypotonic were 2%, 3%, and 4%. I know this because the solutions increased from their before and after mass. The change was positive telling me the solution grew and absorbed water, making it hypotonic.
The cell membrane consists of:
2 layers of phospholipids organized with hydrophobic tails forming the inside of membrane.
An example of simple diffusion would be _____, an example of osmosis would be ______.
A. water being poured into a glass B. the smell of vinegar spreading throughout the room C. blood cells shrinking when placed in salt water D. the absorption of water by a bathroom sponge B; C
Which characteristic is shared by all prokaryotes and eukaryotes?
Ability to store hereditary information
The arrows show the direction of movement of a certain type of particle through the cell membrane of 2 different cells. Which type of transport is illustrated by Cell A?
Active transport
Observed microscopic organisms in pond water
Antonie von Leewenhoek
Which cell specimen is a prokaryote?
Cell 3
A scientist isolates a number of non-photosynthetic prokaryotes. Which structure(s) would be found in these cells?
Cell wall
Identify which structure(s) are present in animal cells.
DNA Nucleus Ribosome
Identify which structure(s) are present in bacterial cells.
DNA Ribosome Cell wall
Materials move through the cell membrane by active transport and passive transport. Which diagram illustrates active transport?
Diagram C
Which 2 transport mechanisms are considered to be passive?
Diffusion and osmosis
The drawing below represents an organism that a student observed while examining a sample of pond water with a light microscope. The student claimed that the organism is prokaryotic. True or False: The student made a correct claim.
False
Which of these best describes an organism's ability to maintain the constant internal conditions necessary for life?
Homeostasis
The solution below is a __________ solution; therefore, water will __________ the cell.
Hypertonic; leave
The solution below is a __________ solution; therefore, water will __________ the cell.
Hypotonic; enter
All plants are made of cells
Matthias Schleiden
Which technology was essential for the development of the cell theory?
Microscope
Which of the following levels of organization best represent the sequence from smallest unit to largest?
Molecule, organelle, cell, organism
Which of the following functions does active transport perform in a cell?
Moving substances from low to high concentration
A student observes cells with the microscope that do not have membrane-bound organelles. Which of these is the most likely cell type?
Prokaryotic cell
The diagram shows an incomplete cross-section of a cell membrane. Three different types of particles are shown moving across the membrane into or out of the cell. Match the appropriate transport mechanism to the type of particle.
Red triangle - chanel Blue circles - phospholipid Yellow squares - ATA pump
Muscle cells are full of fibers made of proteins, so they must have many of this type of organelle to make the fibers.
Ribosomes
Named the "cell"
Robert Hooke
Observed dividing cells
Rudolf Virchos
A sodium-potassium pump within a cell membrane requires energy to move a sodium and potassium ions into or out of a cell (Image 1). When a protein is present, the movement of glucose into or out of a cell does not require energy (Image 2). Which statement BEST describes the movement of these materials across a cell membrane?
Sodium and potassium ions move by active transport; glucose moves by facilitated diffusion.
Which of the solutions were hypertonic to the potato slices? Explain how you know.
The solutions that were hypertonic were 5%, 6%, and 7%. I know this because the solution decreased from their before and after mass. The change was negative tell me the solution shrank and took out water, making it hypertonic.
The drawing below represents an organism that a student observed while examining a sample of pond water with a light microscope. The student claimed that the organism is prokaryotic. Explain the reasoning that you used to determine whether or not the student made the correct claim.
The student is incorrect because the cell has a nucleus and prokaryotic do not have nucleus. Their DNA is spread inside of the cell, there is no storage area for that.
All animals are made of cells
Theodor Schwann
A red blood cell is placed into an aqueous solution. The red blood cell has a lower concentration of protein and sugar than the aqueous solution, as shown in the diagram. In the diagram, the volume of the cell is equal to the volume outside the cell. What is most likely to occur?
Water from the red blood cell will diffuse into the solution.
Carrot sticks that are left in a bowl of fresh water for several hours become stiff and crisp. Carrot sticks left in a salt water solution become limp and soft. This is because fresh water is _______ to the carrot cells and the salt water solution is ______ to the carrot cells.
hypotonic; hypertonic
