The smallest living unit is a _____.
Feedback: Yes; the cell is the basic unit of life and contains the necessary components to present life.
2 Protein synthesis in a bacterial cell is done by _____.
Feedback: Yes; ribosomes are structurally different in bacteria but still are responsible for protein synthesis.
3 The outermost boundary of prokaryotic cells is their _____.
A) plasma membrane
B) nuclear envelope
D) cell wall
Feedback: Yes; the cell wall defines the osmotic boundary of the cell and helps to maintain osmotic regulation.
4 Sperm cells move by means of _______.
D) actin filaments
Feedback: Yes; the long whip-like action of flagella allows sperm cells to move.
5 Skeletal muscle cells will have a large number of _____ due to their high demand for energy.
Feedback: Yes; mitochondria is the source of ATP production and is found in high concentrations in energy requiring muscle cells.
6 All cells contain the following items except ______.
C) plasma membrane
Feedback: Yes; prokaryotes have regions of DNA/RNA molecules but no defined nucleus.
7 The stacks of disks containing chlorophyll in a chloroplast are the ______.
Feedback: Yes; this structure contains pigments and enzymes needed for photosynthesis.
8 Large storage structures typically found in the center of plant cells are ______.
C) Golgi bodies
D) central vacuoles
Feedback: Yes; central vacuoles is a common storage site for substances in plants such as water, etc.
9 Which of the following statements is false?
A) Some cells are large enough to be seen by the naked eye.
B) Cells with infoldings and outfoldings of their plasma membranes are able to move.
C) All cells are shaped like cubes or are round.
D) In Eukaryotic cells, the central nucleus controls activities in the cell.
Feedback: Yes; this is a false statement because there are some muscle and nerve cells which are flat, or long and fiber-like.
10 Cells of more complex organisms are different from bacterial cells in which of the following ways?
A) The presence of cytoplasm
B) The presence of a plasma membrane
C) The variety of organelles and their complexity.
D) The presence of DNA.
Feedback: Yes; eukaryotic cells have much more complexity and size than bacterial components.
11 Which of these organelles contain digestive enzymes?
D) Golgi bodies
Feedback: Yes; this organelle breaks down cell debris and large molecules.
12 Synthesis of lipids occurs in which major organelle?
C) Smooth endoplasmic reticulum
D) Rough endoplasmic reticulum
Feedback: Yes; smooth endoplasmic reticulum is the major site of lipid synthesis.
13 The description "9+2 array" in cells refers to _______.
Feedback: Yes; microtubules are found in cilia, flagella, and centrioles as important structures in movement.
14 When a cell grows, which of the following occurs?
A) They increase in size only.
B) They will develop multiple nuclei.
C) They will increase the volume faster than the surface area of the cell.
D) They will lose their nuclear membranes.
Feedback: Yes; volume does increase faster than the surface area in cells.
15 The large surface area needed for the participants in cellular respiration is provided by the _____ of the mitochondria.
Feedback: Yes; cristae are the membrane structures found in the interior of the chloroplast where diffusion of hydrogen ions powers ATP production.
16 Which of the following will NOT be found in abundance in an insulin-producing pancreas cell?
A) Rough endoplasmic reticulum
B) Golgi apparatus
Feedback: Yes; chloroplasts are functional organelles in plants, not animals.
17 Debris that is trapped in mucus is moved away from the lungs toward the throat by _____.
D) actin filaments
Feedback: Yes; large beds of cilia use wave-like motion to move mucus away from the lungs.
18 The _____ participates in ribosome synthesis and is found in the nucleus.
A) plasma membrane
B) smooth endoplasmic reticulum
C) Golgi apparatus
Feedback: Yes; the nucleolus is found in the interior of the cell and is the site of the synthesis of ribosome components.
19 The endosymbiotic hypothesis attempts to explain _____.
A) the origin of chloroplasts and mitochondria
B) how cells reproduce
C) how photosynthesis occurs
D) the differences between plant and animal cells
The plasma membrane is composed primarily of _____.
D) nucleic acids
2 The tails of the phospholipids are _____.
C) directed inwards in the bilayer
D) All of these
3 The permeability of most membranes is reduced by the presence of _____ in the membrane.
4 Particular molecules or ions freely cross the plasma membrane with assistance from _____.
A) receptor proteins
B) cell recognition proteins
C) channel proteins
D) enzymatic proteins
5 A person's blood type is determined by the presence of particular _____ in the red blood cells' membranes.
D) nucleic acids
6 Which of the following does NOT move freely (without energy or a carrier protein) across the plasma membrane?
7 Osmosis is specifically about the movement of _____ in and out of cells.
8 If the inside of a cell is 1% NaCl, which solution is isotonic to the cell?
A) 0.01% NaCl
B) 0.1% NaCl
C) 1% NaCl
D) 10% NaCl
9 When a plant cell is placed in a hypotonic solution which of the following will occur?
A) The cell will swell and burst.
B) Nothing will occur.
C) The central vacuole gains water.
D) The cell will shrink or shrivel up.
10 The term hemolysis refers to ______.
A) normal red blood cells
B) red blood cells that burst after being placed in a hypotonic solution
C) shrinking of the cytoplasm after a cell is placed in a hypertonic solution
D) the loss of turgor pressure in a plant cell
11 Which of the following correctly describes facilitated transport?
A) It requires the expenditure of energy.
B) Molecules move from high concentration to low concentration.
C) Vacuoles form to move materials.
D) All of the above.
12 Insulin leaves insulin-secreting cells by _____.
B) receptor-mediated endocytosis
13 The peptide hormone, follicle stimulating hormone, would activate its specific target cells by _____.
A) diffusing into the cells
B) binding a receptor protein in the plasma membranes
14 Heart cells are able to contract in unison because of the flow of ions through _____.
A) gap junctions
B) tight junctions
C) adhesion junctions
15 People may get injections of _____, a component of the extracellular matrix of animal cells, to get rid of their wrinkles.
16 Which of the following correctly describes active transport?
A) Carrier proteins are needed.
B) It requires the expenditure of energy.
C) Molecules move from areas of low concentration to areas of high concentration.
D) All of these.
Feedback: Yes; all of these are characteristics or factors involved in active transport.
17 Macrophages, immune system cells, engulf bacteria by _____.
B) facilitated transport
18 The amount of phospholipid extracted from red blood cells led researchers to propose that ____.
A) the phospholipids form a single layer around the cell
B) the phospholipids form a bilayer around the cell
C) there are not enough phospholipids to create a membrane around the cell
19 According to the fluid-mosaic model, _____ are partially or wholly embedded in a fluid phospholipid bilayer.
A) nucleic acids
20 Transplant rejections are the result of the immune system's response to foreign ______ and __________.
A) DNA, RNA
B) glycoproteins, glycolipids
C) plasma membranes; glycolipids