Chapter 4: Tour of the Cell

1 meter = _____ centimeters. 1,000 100 1,000,000,000 1,000,000 1,000,000,000,000

100

Which of the following statements about plant cell walls is false? Plant cell walls are multilayered structures. Plant cell walls consist of cellulose fibers embedded in a matrix of polysaccharides and proteins. Plant cell walls protect plant cells by forming an impermeable layer around the cell. Wood is primarily composed of plant cell walls.

Plant cell walls protect plant cells by forming an impermeable layer around the cell.

Which of the following statements regarding plasmodesmata is false? Plasmodesmata are found in plants and animals. Plasmodesmata carry nutrients between plant cells. Plasmodesmata penetrate plant cell walls. Plasmodesmata carry chemical messages between plant cells.

Plasmodesmata are found in plants and animals.

What name is given to the process in which pre-mRNA is edited into mRNA? RNA processing gene expression polypeptide formation transcription translation

RNA processing

How are cell surface proteins exported out of the cell? View Available Hint(s) The protein is folded, then packaged for transport to the Golgi apparatus. The protein will be sent to the smooth endoplasmic reticulum to be sorted for its final destination. The proteins are packaged into vesicles for transport to the lysosomes. The protein will be modified with the addition of a monosaccharide.

The protein is folded, then packaged for transport to the Golgi apparatus.

The membranous compartmentalization of a cell is common to both prokaryotes and eukaryotes. requires the presence of a cell wall. divides the cell into two equal-sized halves. allows different chemical conditions to be maintained in different parts of the cell.

allows different chemical conditions to be maintained in different parts of the cell.

Polypeptides are assembled from _____. hexoses glycerol nucleotides proteins amino acids

amino acids

In the plasma membrane, the phospholipid heads are hydrophilic and face inward, shielded from water. are hydrophilic and face outward toward the aqueous solution on both sides of the membrane. are hydrophobic and face inward, shielded from water. are hydrophobic and face outward toward the aqueous solution on both sides of the membrane.

are hydrophilic and face outward toward the aqueous solution on both sides of the membrane.

Which is a typical function of lysosomes? View Available Hint(s) storage of food particles for energy purposes breaking down of damaged organelles, such as mitochondria keeping bacteria within a safe, contained environment rebuilding macromolecules, such as glycoproteins

breaking down of damaged organelles, such as mitochondria

A scanning electron microscope is used to study ________, whereas a transmission electron microscope is used to study ________. internal cell structures; cell surfaces dead cells; live cells cell surfaces; internal cell structures live cells; dead cells

cell surfaces; internal cell structures

The function of mitochondria is lipid synthesis. intracellular digestion. photosynthesis. cellular respiration.

cellular respiration

Which cellular organelle is required for photosynthesis to occur in eukaryotic cells? View Available Hint(s) lysosome chloroplast nucleus Golgi apparatus

chloroplast

organelle of photosynthesis found only in plant cells and some algae contains thylakoids converts solar energy to chemical energy produces O2 as a waste product

chloroplast

Cilia differ from flagella in that cilia are anchored only in the proteins of the cell membrane, whereas flagella are anchored in a special structure called the basal body. the protein filaments of cilia are "naked," whereas those of flagella are wrapped in an extension of the cell membrane. cilia contain nine microtubule doublets surrounding a central pair of microtubules, whereas flagella contain only nine microtubule doublets. cilia are typically more numerous and shorter than flagella.

cilia are typically more numerous and shorter than flagella.

The nucleoid region of a prokaryotic cell contains the cell's DNA. separates the RNA from the cytoplasm. is surrounded by a nucleoid membrane. contains the cell's nucleoli.

contains the cell's DNA.

What mitochondrial feature enhances cellular respiration? View Available Hint(s) cristae matrix intermembrane space mitochondrial DNA

cristae

Bacterial cells are prokaryotic; unlike a typical eukaryotic cell, they _____. View Available Hint(s) have more internal membranous compartments have a smaller nucleus lack a plasma membrane lack a nucleus

lack a nucleus

RNA processing converts the RNA transcript into _____. a protein DNA a eukaryotic cell mRNA a polypeptide

mRNA

Which of the following cytoplasmic structures functions in the transport of vesicles from the endoplasmic reticulum to the Golgi apparatus? View Available Hint(s) microtubules actin filaments intermediate filaments microfilaments

microtubules

The internal skeleton of a cell is composed of _____. View Available Hint(s) microfilaments microtubules, intermediate filaments, and microfilaments cellulose, microtubules, and centrioles cellulose and intermediate filaments

microtubules, intermediate filaments, and microfilaments

organelle of cellular respiration found in both animal cells and plant cells harvests chemical energy from food produces CO2 as a waste product

mitochondria

The membranes of the endoplasmic reticulum are continuous with the membranes of the __________. View Available Hint(s) Golgi apparatus mitochondria nuclear envelope lysosomes

nuclear envelope

Structures found within a eukaryotic cell and performing specific tasks are collectively termed __________. View Available Hint(s) prokaryotes the Golgi apparatus endoplasmic reticulum organelles

organelles

Which location in the cell is unlikely to contain ribosomes or ribosomal subunits? nuclear envelope cytoplasm plasma membrane endoplasmic reticulum

plasma membrane

Contractile vacuoles help in the excretion of excess salt. are generally found in protists that inhabit salt water. prevent cells from bursting as a result of the influx of excess water. allow organisms to avoid dehydration by absorbing water from the environment.

prevent cells from bursting as a result of the influx of excess water.

In muscle cells, the _____ is/are specialized for the storage and release of calcium. View Available Hint(s) mitochondria smooth endoplasmic reticulum rough endoplasmic reticulum the Golgi apparatus

smooth endoplasmic reticulum

The term resolving power refers to _____. View Available Hint(s) the depth of focus the clarity of the image in showing two objects as separate the source of the illumination the apparent increase in the size of an object

the clarity of the image in showing two objects as separate

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? RNA processing gene expression polypeptide formation transcription translation

transcription

What name is given to the process in which the information encoded in a strand of mRNA is used to construct a protein? RNA processing gene expression polypeptide formation transcription translation

translation

Light microscopes use light and glass lenses to magnify an image. are generally not used to view bacteria. work by reflecting electrons off the surface of an object being studied. typically provide more resolution than an electron microscope.

use light and glass lenses to magnify an image.

Which of the following statements regarding the endomembrane system is false? The endomembrane system includes the rough and smooth endoplasmic reticulum. The endomembrane system includes the nuclear envelope. The endomembrane system is involved in the synthesis, storage, and export of important molecules. The endomembrane system is a system of interrelated membranes that are all physically connected.

The endomembrane system is a system of interrelated membranes that are all physically connected.

What is the relationship between the Golgi apparatus and the plasma membrane? View Available Hint(s) The membranes of the Golgi apparatus and the plasma membrane are continuous. The plasma membrane stops the products of the Golgi apparatus from leaving the cell. The finished products of the Golgi apparatus may leave the cell through vesicles that fuse with the plasma membrane. The Golgi apparatus begins the formation of the lipids that make up plasma membranes.

The finished products of the Golgi apparatus may leave the cell through vesicles that fuse with the plasma membrane.

The endosymbiosis hypothesis proposes that a small cell lived inside a larger cell to the benefit of both cells. a large cell engulfed and digested a smaller cell, exposing its enzymes for use by the larger cell. two separate cells worked cooperatively and one benefited from the other. two cells merged into one cell, improving the enzyme function of the new cell.

a small cell lived inside a larger cell to the benefit of both cells.

Mitochondria differ from chloroplasts in that mitochondria contain three different membrane-bound compartments, whereas chloroplasts contain two. convert light energy from the sun to chemical energy, whereas chloroplasts convert one form of chemical energy to another. contain membrane folds called cristae, whereas chloroplasts contain disk-like vesicles in stacks called grana. are not found in plants, whereas chloroplasts are not found in animals.

contain membrane folds called cristae, whereas chloroplasts contain disk-like vesicles in stacks called grana.

1. DNA is the self-replicating material present in nearly all living organisms; it is the main constituent of chromosomes and the carrier of genetic information. 2. RNA is used in all steps of protein synthesis and carries the genetic information of many viruses. 3. The nucleus is the most prominent membrane-bound organelle in eukaryotic cells, and it houses most of a cell's DNA. 4. The nuclear envelope is the two-layered membrane that encases the nucleus of a eukaryotic cell, separating the nucleus from the cytoplasm. 5. A protein-lined channel in the nuclear envelope that regulates the transportation of molecules between the nucleus and the cytoplasm is called a nuclear pore. 6. The round body that sits inside the nucleus of a eukaryotic cell and makes ribosomal subunits from proteins and ribosomal RNA is known as the nucleolus. 7. Chromosomes are tightly coiled bundles of DNA and protein found in the nucleus of most living cells.

just read

Lysosomes are derived from __________ and function in __________. View Available Hint(s) microtubule organizing centers ... storage of ATP symbiotic bacteria ... extrachromosomal inheritance the Golgi apparatus and rough endoplasmic reticulum ... digestion of worn-out organelles mitochondria ... anaerobic respiration

the Golgi apparatus and rough endoplasmic reticulum ... digestion of worn-out organelles

Membrane proteins are synthesized by ribosomes that are attached to __________. View Available Hint(s) the endoplasmic reticulum the Golgi apparatus the nucleolus lysosomes

the endoplasmic reticulum