AP Bio Ch 4 Outline Quiz

The statement is true because a cell is indeed the smallest unit of living matter. Cells are the basic building blocks of all living organisms and are responsible for carrying out all the necessary functions of life. They are capable of reproducing themselves and have the ability to perform various specialized functions within multicellular organisms. Without cells, life as we know it would not exist.

The cell theory does not state that bacteria and other small organisms can arise spontaneously. According to the cell theory, all cells come from preexisting cells, and it is accepted today by biologists as applying to virtually all forms of life. The various parts of the cell theory were described by Schleiden, Schwann, and Virchow.

This statement is false because not all cells have a cell wall. In fact, only certain types of cells, such as plant cells and bacterial cells, have a cell wall. Animal cells, on the other hand, do not have a cell wall. The cell wall is a rigid structure that provides support and protection to the cell, but it also restricts the passage of molecules. Therefore, it is incorrect to say that all cells have a cell wall.

B cells, also known as B lymphocytes, are a type of white blood cell that plays a crucial role in the immune response. They are surrounded by a plasma membrane, which acts as a barrier and separates the internal contents of the B cell from its external environment. This membrane is made up of a phospholipid bilayer with embedded proteins that help regulate the entry and exit of substances into and out of the cell. Therefore, the statement "B cells are surrounded by a plasma membrane" is true.

Eukaryotic cells contain ribosomes that are larger than those of prokaryotic cells. Ribosomes in eukaryotic cells are generally 80S, while ribosomes in prokaryotic cells are 70S. This is because eukaryotic cells have more complex protein synthesis machinery, requiring larger ribosomes.

The correct answer is the immunofluorescence microscope. This type of microscope uses antibodies that are labeled with fluorescent dyes to specifically bind to a target protein in a cell. When the antibodies bind to the protein, they emit fluorescence, allowing the location of the protein to be visualized under the microscope. This technique is commonly used in cell biology and immunology research to study the localization and distribution of proteins within cells.

The statement "Their cell wall is made of a slime layer that is the same as in plant cell walls" is not true about bacteria. Bacteria have a cell wall made of peptidoglycan, which is different from the cellulose-based cell walls found in plant cells.

The correct answer is scanning electron microscope (SEM). A scanning electron microscope is a high-powered microscope that uses a beam of electrons to scan the surface of a sample. It produces an image by detecting the scattered secondary electrons. This allows for detailed imaging of the sample's surface, making it useful for examining the topography and composition of materials at a high resolution. Immunofluorescence microscope, bright-field light microscope, transmission electron microscope (TEM), and confocal microscope do not utilize scattered secondary electrons for imaging.

Chlorophylls are actually found in the thylakoid membranes of the chloroplast, not in the fluid stroma. The stroma is the fluid-filled space surrounding the thylakoid membranes. It is where the second stage of photosynthesis, known as the Calvin cycle, takes place. The thylakoid membranes, on the other hand, contain the pigments, including chlorophylls, that capture the solar energy needed for photosynthesis.

Actin filaments, also known as microfilaments, are able to assemble and disassemble from component proteins. This property allows them to dynamically change their structure and function in response to cellular needs. Actin filaments play a crucial role in various cellular processes such as cell movement, muscle contraction, and cell division. They are composed of actin proteins that can polymerize to form long filaments or depolymerize to break them down, providing flexibility and adaptability to the cell.