Chapter 4 MB Activities
What is the function of a bacterium's capsule?
protection
What is the function of Structure E?
Cholesterol helps to stabilize the structure of the plasma membrane.
_____ are surface appendages that allow a bacterium to stick to a surface.
Fimbriae
Which of these provides the cell with structural support?
Microfilaments are a component of the cytoskeleton.
Which of these organelles carries out cellular respiration?
Mitochondria: Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.
Which of these organelles produces H2O2 as a by-product?
Peroxisomes: produce hydrogen peroxide as a by-product of their metabolic processes.
Identify Structure D.
Phospholipids can be recognized by the presence of a head and two tails.
What name is given to the process in which pre-mRNA is edited into mRNA?
RNA processing: edits the RNA transcript that has been assembled along a DNA template.
Which of these manufactures cellular membranes by adding membrane proteins andphospholipids to its own membrane?
Rough endoplasmic reticulum: As membrane proteins grow from ribosomes on rough ER, the proteins areembedded into the rough ER membrane.
Where is calcium stored?
Smooth endoplasmic reticulum:In addition to storing calcium, the smooth ER also plays a role in detoxification and lipid synthesis.
The DNA-containing region of this bacterial cell is indicated by the letter _____.
The nucleoid region contains DNA.
Choose the letter that indicates the organelle that contains most of a cell's DNA.
The nucleus contains most of a cell's DNA.
Polypeptides are assembled from _____.
amino acids
_____ is/are identical in structure to centrioles.
basal bodies
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.
c: The plasma membrane is selectively permeable.
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?
cell wall
Which organelles comprise the endomembrane system of a cell?
endoplasmic reticulum, Golgi apparatus, lysosome
The ____________________ builds compounds, whereas the ________________ breaks things down.
endoplasmic reticulum; lysosome
Identify Structure A.
glycoprotein :Structure A is composed of both a carbohydrate and a protein.
RNA processing converts the RNA transcript into _____.
mRNA
The cilia and flagella of eukaryotic cells are composed of _____.
microtubules
Which of these are hollow rods that shape and support the cell?
microtubules :Microtubules are rods that also play a role in organelle movement.
Which of these is the double membrane that encloses the nucleus?
nuclear envelope
Where is a bacterial cell's DNA found?
nucleoid region
Ribosomal subunits are manufactured by the _____.
nucleolus
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.
plasma membrane
Animal cells are surrounded by a(n) ________________, whereas plant cells are also surrounded by a(n) ________________ .
plasma membrane; cell wall
When using a microscope to view cells you obtained from scraping under your fingernails, you notice that the cells lack nuclei; therefore, you conclude that the cells must be a type of ________ cell.
prokaryotic
In a bacterium, where are proteins synthesized?
ribosomes
_____ are the sites of protein synthesis.
ribosomes
Examine the structures of the plant and animal cells below. Which of the following organelles connect(s) to the nuclear envelope?
the endoplasmic reticulum
In eukaryotic cells the first step in protein synthesis is the _____.
transferring of information from DNA to messenger RNA
Which of these structures stores, modifies, and packages products?
The Golgi apparatus modifies, stores, and packages products of the ER.
What are the three organelles that plant cells have but animal cells do not?
chloroplast, central vacuole, cell wall
Plant cells have two energy-related organelles. ________________ harness light energy to create sugars and ________________ break down these sugars to create ATP.
chloroplasts; mitochondria
The _____ is composed of DNA and protein
chromatin
The figure below shows a Paramecium, a single-celled freshwater protist. The hairlike structures visible on the Paramecium allow it to move. These structures are ________.
cilia
Which organelle plays a role in intracellular digestion?
lysosome :The prefix "lyso-" means decomposition
What name is given to the process in which a strand of DNA is used as a template for the manufacture of a strand of pre-mRNA?
transcription
What name is given to the process in which the information encoded in a strand of mRNA is used to construct a protein?
translation