Biology Chapter 4 HW
_____ aid in the coordination of the activities of adjacent animal cells.
Gap (communicating) junctions
A normal size range for a typical eukaryotic cell is _____.
10 to 100 micrometers
1 meter = _____ centimeters.
100
Most of the DNA in a eukaryotic cell is in the _____.
Nucleus
Which of the following statements about the cytoskeleton is false?
Once laid down, the elements of the cytoskeleton are fixed and remain permanently in place.
________ cells lack a membrane-enclosed nucleus.
Prokaryotic
What is the relationship between the Golgi apparatus and the plasma membrane?
The finished products of the Golgi apparatus may leave the cell through vesicles that fuse with the plasma membrane.
The membranous compartmentalization of a cell
allows different chemical conditions to be maintained in different parts of the cell.
A certain cell has a dense nucleoid region, ribosomes, but no membrane-enclosed organelles. Based on this information, it could be __________.
an archaean
In the plasma membrane, the phospholipid heads
are hydrophilic and face outward toward the aqueous solution on both sides of the membrane.
Which is a typical function of lysosomes?
breaking down of damaged organelles, such as mitochondria
The function of mitochondria is
cellular respiration
What are the inner folds of the mitochondria called?
cristae
What mitochondrial feature enhances cellular respiration?
cristae
The primary role of _____ is to bind animal cells together.
desmosomes
Which of the following structures is directly involved in the passage of electrical signals between cells as, for example, in the vertebrate heart?
gap junctions
Bacterial cells are prokaryotic; unlike a typical eukaryotic cell, they _____.
lack a nucleus
The cells of a person with adrenoleukodystrophy (ALD) swell with a buildup of fatty acids. In other words, fatty acids are not being broken down. Which organelle is most likely failing to function correctly?
lysosome
Which of the following organelles is found only in animal cells and NOT in most plant cells?
lysosome
Mitochondria appear in the greatest numbers in cells that are _____.
metabolically active
The cilia and flagella of eukaryotic cells are composed of _____.
microtubules
The membranes of the endoplasmic reticulum are continuous with the membranes of the __________.
nuclear envelope
Most of the DNA in a eukaryotic cell is in the _____.
nucleus
Where is the genetic information of the cell stored? The structural framework in a cell is the Where in a cell is ATP made? What carries instructions for making proteins from the nucleus into the cytoplasm? One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by Which of the following is part of the endomembrane system? Which of the following organelles breaks down worn-out organelles? Where are lipids made in the cell? What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?
nucleus cytoskeleton. mitochondria mRNA ribosomes. Golgi apparatus lysosomes smooth endoplasmic reticulum (ER) plasma membrane
Which organelle is involved in the breakdown of fatty acids and the detoxification of alcohol?
peroxisome
The function of chloroplasts is
photosynthesis
You have identified a new organism. It has ribosomes, plasmodesmata, and cell walls made of cellulose. This new organism is most likely a(n) __________.
plant
Chloroplasts are found in __________.
plant cells and some protists
Which plant structure is most like gap junctions in animal cells?
plasmodesmata
Archaea are composed of ________ cells.
prokaryotic
The architecture of cell surfaces can be viewed in the most detail using a __________.
scanning electron microscope
Which tissue would likely contain large amounts of anchoring junctions?
stomach tissue
What are the limits on which maximum cell size depends?
surface-to-volume ratio
Membrane proteins are synthesized by ribosomes that are attached to _____.
the endoplasmic reticulum
Membrane proteins are synthesized by ribosomes that are attached to __________.
the endoplasmic reticulum
To enter or leave any cell, substances must pass through _____.
the plasma membrane
GPCRs are receptor proteins found in the plasma membrane that are important for cellular communication. What cellular structure makes GPCRs?
the rough endoplasmic reticulum
Which of these cell junctions form a barrier to the passage of materials?
tight junctions
The function of the nucleolus is
to manufacture ribosomal RNA.
A pathologist who wants to examine a patient's liver cells to determine if the mitochondria have an internal structural defect will likely need to use a
transmission electron microscope.
Light microscopes
use light and glass lenses to magnify an image.
As cell size increases, the
volume increases proportionally more than the surface area.
Which of the following clues would tell you whether a cell is prokaryotic or eukaryotic?
whether or not the cell is partitioned into compartments by internal membranes
Which of the following cells has the greatest surface-to-volume ratio?
bacterium
Which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell? The plant cell wall Which of the following is a function of the central vacuole? _____ are found only in plant cells, but _____ are found in both plant and animal cells. Which of the following describes the function of the chloroplast?
Mitochondrion is a protective structure made of cellulose fibrils. Storing compounds produced by the cell Central vacuoles; ribosomes The chloroplast converts light energy to chemical energy.
