Chapter 4: Evolutionary Origin of Cells and Their General Features
Function of Cell Wall
1. Supports and protects the plasma membrane and cytoplasm. 2. Its porous structure allows most nutrients to reach the plasma membrane.
In the cilia and flagella of most eukaryotes, the microtubules are arranged in a "9 + 2" array. This refers to the presence of: 9 central single microtubules and 2 outer doublet microtubules 9 outer doublet microtubules and 2 central single microtubules 9 central doublet microtubules and 2 outer single microtubules 9 outer single microtubules and 2 central doublet microtubules
9 outer doublet microtubules and 2 central single microtubules
Which statement best describes the cytosol? A central region that coordinates many metabolic activities An external region that aids in cell movement A central region that contains the genetic material An external region that protects the cytoplasm
A central region that coordinates many metabolic activities
Which statement best describes the cytosol? A central region that coordinates many metabolic activities An external region that aids in cell movement An external region that protects the cytoplasm A central region that contains the genetic material
A central region that coordinates many metabolic activities
Polypeptides
A linear organic polymer consisting of a large number of amino-acid residues bonded together in a chain, forming part of (or the whole of) a protein molecule
Which of the following describes an organelle? Multiple choice question. A membrane-bound structure on the outside of all cells The site of protein synthesis A membrane-bound component with its own unique structure and function.
A membrane-bound component with its own unique structure and function.
Which of these statements best describes actin filaments?
A spiral of two intertwined strands of protein
Enzyme
A type of protein that speeds up a chemical reaction in a living thing
How big is a typical eukaryotic cell? About 100-200 μm in diameter About 10-100 μm in diameter About 200-500 μm in diameter About 1-10 μm in diameter
About 10-100 μm in diameter
Function of Chloroplasts
Aid in photosynthesis
Vacuoles
Appear to be empty compartments yet contain fluid and sometimes solid substances. Many made from fusion of smaller membrane vesicles.
Glycosylation
Attachment of carbohydrates to proteins and lipids.
Motor Proteins
Category of proteins that use ATP as a source of energy to promote various types of movements
Centrioles
Cell organelle that aids in cell division in animal cells only
What best explains why most cells are small?
Cells must be small to be able to take up nutrients efficiently.
Ribosome subunits
Cellular structures involved in producing polypeptides during the process of translation
Cilia and flagella are two types of cell appendages that use which of these to facilitate movement? Actin filaments and motor proteins Microtubules and intermediate filaments Microtubules and motor proteins
Cilia and flagella are two types of cell appendages that use which of these to facilitate movement?
Axoneme
Core of eukaryotic cilia and flagella consisting of microtubules, the motor protein dynein, and linking proteins
Basal Body/Centriole
Cylindrical organelle near the nucleus. Occurs in pairs.
Select all the locations where ribosomes can be found in the cell. Cytosol Endoplasmic reticulum Golgi apparatus Chloroplasts Central vacuole mitochondria
Cytosol Endoplasmic reticulum Chloroplasts Mitochondria
Nuclear envelope
Double membrane structure that encloses the nucleus
What are the functions of the capsules that some bacteria produce? They aid in attachment to cell surfaces. They synthesize polypeptides. They prevent animals' immune systems from destroying bacterial cells. They aid in motility They substitute for the cell wall and protect from osmotic lysis.
They aid in attachment to cell surfaces. They prevent animals' immune systems from destroying bacterial cells.
What are the functions of the capsules that some bacteria produce? They aid in motility They aid in attachment to cell surfaces. They substitute for the cell wall and protect from osmotic lysis. They prevent animals' immune systems from destroying bacterial cells. They synthesize polypeptides.
They aid in attachment to cell surfaces. They prevent animals' immune systems from destroying bacterial cells.
Actin Filaments
Thin type of protein filament composed of actin proteins that forms part of the cytoskeleton and supports the plasma membrane: plays a key role, in shape, movement, and cell strength. Highly concentrated near the plasma membrane
Endomembrane system
This system includes nuclear envelope, which encloses the nucleus, as well as the endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, peroxisomes and plasma membrane.
Which of these is a reason for catabolism? To synthesize carbohydrates To glycosolate a molecule To provide building blocks To synthesize proteins
To provide building blocks
Identify the two reasons that catabolism is necessary. To utilize energy To provide building blocks To synthesize molecules
To utilize energy To provide building blocks
Select all of the statements that explain how different cells in the same organism produce different proteomes. Multiple select question. Two different cell types may produce different amounts of the same protein. Different cell types may alter their proteins in different ways. There may be differential gene regulation and alternative splicing. Different cells in the same organism have different genes. Different cells can use different types of ribosomes for translation.
Two different cell types may produce different amounts of the same protein. Different cell types may alter their proteins in different ways. There may be differential gene regulation and alternative splicing.
Microtubules
Type of hollow protein filament composed of tubulin proteins that is part of the cytoskeleton and is important for cell shape, organization, and movement
Intermediate Filaments
Type of protein filament in the cytoskeleton that functions as tension bearing fibers which helps maintain shape and rigidity of the cell
Flagella
Typically found in pairs. Produce movement by generating bends that move along the length and push backwards against the surrounding fluid
Nucleolus
Where the assembly of ribosome subunits occurs
Is it possible for cells from the same multicellular organism to have different proteomes? Yes, because cells have different structures. No. All cells from the same organism have the same proteome. Yes, because cells contain different genes. Yes, because cells produce different proteins.
Yes, because cells produce different proteins.
Is it possible for cells from the same multicellular organism to have different proteomes? Yes, because cells have different structures. Yes, because cells produce different proteins. No. All cells from the same organism have the same proteome. Yes, because cells contain different genes.
Yes, because cells produce different proteins.
The size of a larger organism is usually attributed to: cells that are much larger cells that contain more than one nucleus cells that have a small surface area to volume ratio a greater number of cells
a greater number of cells
The size of a larger organism is usually attributed to:cells that have a small surface area to volume ratio cells that are much larger cells that contain more than one nucleus a greater number of cells
a greater number of cells
When compared to a mouse, an elephant has: roughly the same number of cells, but these cells are very large about the same-sized cells, but many more of them
about the same-sized cells, but many more of them
An enzyme is a protein that ______ the rate of a chemical reaction.
accelerates
Microfilaments is another name for
actin filaments
The head of a motor protein is where ______ causing a bend in the hinge. adenosine triphosphate (ATP) binds and is hydrolyzed to ADP adenosine diphosphate (ADP) binds and is hydrolyzed to ATP
adenosine triphosphate (ATP) binds and is hydrolyzed to ADP
What are the building blocks of proteins?
amino acids
Cellular molecules and macromolecules are produced by:
anabolism
The synthesis of cellular molecules and macromolecules occurs via a process termed . _____________
anabolism
The synthesis of cellular molecules and macromolecules occurs via a process termed __________
anabolism
Flagella and cilia have an internal structure called a(n) ______ , which contains microtubules, dynein, and linking proteins.
axoneme
Some bacteria produce a thick, gelatinous glycocalyx called a(n) ______, which aids in attachment and prevent their destruction by the host immune system.
capsule
What are the common components of the prokaryotic cell wall?- think, carberry is peppy carbohydrates nucleic acids phospholipids peptides
carbohydrates and peptides
______ consists of the metabolic reactions that break down larger molecules into smaller components.
catabolism
Nearly all species of archaea and bacteria have rigid ______ ________ that supports and protects the plasma membrane and cytoplasm.
cell wall
Within the centrosome, there is a pair of structures arranged perpendicular to each other called the
centrioles
Nondividing animal cells contain a single structure near their nucleus called the _____________-, or microtubule-organizing center.
centrosome
What structure is found in plant cells but not in animal cells? Centriole Chloroplast Chromatin Mitochondrion
chloroplasts
Basal bodies are anchored to the exterior side of the plasma membrane centrosome golgi apparatus cytoplasmic side of the plasma membrane
cytoplasmic side of the plasma membrane
Intermediate filaments and actin compose this cell structure: cytoskeleton ribosome chloroplast cytoplasm
cytoskeleton
Intermediate filaments and actin compose this cell structure:] cytoplasm chloroplast ribosome cytoskeleton
cytoskeleton
In eukaryotes, the ______is the region of a eukaryotic cell that is outside the membrane-bound organelles but inside the plasma membrane.
cytosol
The location of the cytoskeleton is primarily in the ____________ but also in the nucleus along the inner nuclear membrane.
cytosol
What term describes the region of a eukaryotic cell that is outside the membrane-bound organelles but inside the plasma membrane?
cytosol
the ___ is the region that is enclosed by the plasma membrane but outside the organelles. It is the location of chemical reactions by which cells produce the materials and utilize the energy necessary to sustain life.
cytosol
The cytoskeleton is located in the: chloroplast cytosol nucleus ribosome
cytosol nucleus
Some organelles form when aggregated solutes, such as proteins and RNA molecules, separate from the bulk solvent and form a complex. These are called ________________organelles.
droplet organelle
The main function of the glycocalyx is to prevent a bacterium from:
drying out
What term describes the oscillation of a single microtubule between growing and shortening phases? Dynamic oscillation Dynamic instability Dynamic variability
dynamic instability
Which protein is activated to walk toward the basal body of the microtubules during the bending of flagella and cilia? Tubulin Dynein Myosin Actin
dynein
In eukaryotes, the endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, nuclear envelope, and plasma membrane form a network of membranes called the _____ _____
endomembrane
a ______ is a protein that accelerates the rate of a chemical reaction.
enzyme
Aside from bacteria and archaea, all other species are .
eukaryote
True or false: All of the cells of a given species have the same shape, size, and organization.
false
True or false: Plant and animal cells have identical internal organelles and structures.
false
What is used by prokaryotes to move? Cilia Motility organ Prokaryotes move by fluid convection only Flagella
flagella
___ are long, threadlike structures, which are used to provide motility to bacterial cells.
flagella
____ are appendages used by prokaryotic cells to move.
flagella
The two types of cell appendages that use microtubules and motor proteins to facilitate movement are ______ and _______-
flagella and cilia
Cisternae
flattened stacked membrane folds
As the volume of a cell increases, the surface area/volume ratio:
gets smaller
The outer gelatinous covering surrounding some bacteria is called the:
glycocalyx
Genetic material can be found in all of these organelles except:
golgi apparatus
List the three domains of a motor protein. hinge tail head middle
hinge] tail head
A _____ filament has a staggered alignment of different proteins such as keratin and lamin and may be found in such places as skin and kidney cells.
intermediate
What property of the cell wall allows nutrients in the environment to reach the plasma membrane?
it is pourous
Droplet organelles are a recently-discovered phenomenon. They are not surrounded by any membranes. Rather, they form via a mechanism called______________ -_____________ _______________ separation.
liquid-liquid phase
What term describes the chemical processes that occur within living cells in order to maintain life?
metabolism
______________ is defined as the sum of the chemical reactions by which cells produce the materials and utilize the energy that is necessary to sustain life.
metabolism
__________are long, hollow, cylindrical structures about 25 nm in diameter and composed of the protein tubulin.
microtubules
What property do flagella provide to bacterial cells?
motility
______ proteins are a category of proteins that use ATP as a source of energy to promote various types of movements.
motor proteins
The nucleus is enclosed by a double membrane structure called the __________ ___________--
nuclear envelope
The double membrane structure that surrounds the nucleus is the: plasma membrane nuclear envelope nuclear matrix
nuclear matrix
In bacteria, the genetic material is located in a region of the cytoplasm called the .
nucleoid
Which of the following is an example of a droplet organelle? Leukoplast Nucleolus Peroxisome Lysosome
nucleous
In bacteria, the genetic material is located in a region of the cytoplasm called the
nucleuoid region
In eukaryotic cells, most of the DNA is housed in an internal compartment, or organelle, called the (one word).
nucleus
The______- is an organelle in eukaryotic cells that contains most of the cell's genetic material.
nucleus
Where is most of the DNA located in a eukaryotic cell?
nucleus
the _____ is an organelle in eukaryotic cells that contains most of the cell's genetic material.
nucleus
The general term used to describe a membrane-bound structure within a cell that has its own unique structure and function is .
organelle
Eukaryotic cells have many membrane-bound compartments called____ , whereas prokaryotic cells do not exhibit compartmentalization.
organelles
What are the common components of the prokaryotic cell wall? Peptides Phospholipids nucleic acids carbohydrates
peptides carbohydrates
Although cell wall composition varies widely amongst prokaryotes, they commonly contain
peptides and carbohydrates
Hairlike projections on bacterial cells called _______allow bacteria to attach to surfaces as well as to each other.
pili
Hairlike projections on bacterial cells called_____allow bacteria to attach to surfaces as well as to each other.
pilli
What describes the cell wall of prokaryotic cells? impermeable to most nutrients studded with special protein channels strictly impermeable and water-tight relatively porous
pourus
All the proteins in a cell make up the:
proteome
The complete protein composition of a cell or organism is called the .
proteome
What describes the cell wall of prokaryotic cells? relatively porous impermeable to most nutrients studded with special protein channels strictly impermeable and water-tight
relatively porous
Droplet organelles provide an environment where molecules that are brought closer together can easily accumulate into complexes. An example is the assembly of ____________subunits in the nucleolus.
ribosomal
Structures called_______ are found in both prokaryotic and eukaryotic cells and are the sites of polypeptide synthesis.
ribosomes
Translation occurs on ________, which are found in various locations in the cell.
ribosomes
The cell walls of most bacteria and archaea are
rigid
Select all of the following that can vary in the cells of eukaryotic species. Multiple select question. type of nucleic acid used to store genetic information shape size types of organelles
shape size types of organelles
Catabolism involves the breakdown of a molecule into ______ components.
smaller
Cells are typically small because as cell size increases, the surface area and volume increase at the same rate. the volume and surface area decrease. the surface area increases faster than the volume. the volume increases faster than the surface area.
the volume increases faster than the surface area.
The process by which proteins are made using the information within an mRNA is called .
translation
What is the process of polypeptide synthesis?
translation
True or false: Dynamic instability means that a single microtubule can oscillate between growing and shortening phases.
true
The process by which proteins are made using the information within an mRNA is called. actin tubulin peptin flagellin
tubulin
List the three different types of protein filaments that make up the cytoskeleton: Enzyme filaments Intermediate filaments Microtubules Actin
Intermediate filaments Microtubules Actin
Function of Basal Body/Centriole
Involved in development of spindle fibers during cell division
Smooth ER
Lacks ribosomes
Which of the following is the best reason for cells being small? Larger cells would require more nutrients and there is usually a limited supply. Larger cells would not be able to get necessary gases and nutrients quickly enough. Larger cells would create too much heat and enzymes will denature. The cell membrane can only stretch so much and so cannot accommodate the larger size.
Larger cells would not be able to get necessary gases and nutrients quickly enough.
Which of the following mechanisms is thought to play a role in the formation of droplet organelles? Cellular abiogenesis Passive compartmentalization Secondary endosymbiosis Liquid-liquid phase transition
Liquid-liquid phase transition
Flagella
Long appendages that provide prokaryotic cells with a way to move, also called motility
Centrosome
Microtubule-organizing center
Which of the following are examples of fungi? Paramecia Algae Molds Yeasts
Molds Yeasts
Rough ER
Network of membranes that form flattened, fluid filled tubules. Studded with ribosomes
Where is the DNA housed in a bacterial cell?
Nucleoid region
List the cell structures within the bacterial cytoplasm that are visible via an electron microscope. Nucleus Nucleoid region ribosomes amino acids
Nucleoid region ribosomes
Which of these organisms are examples of protists?Paramecia Bacteria Mushrooms Yeasts Algae
Paramecia Algae
Catabolism
Pathways that involve the breakdown of a molecule into smaller components
Peroxisomes
Peroxisomes are small organelles found in all eukaryotic cells. Consist of singe membrane that encloses lumen. Many are found in liver of animal cells.
What structures allow bacteria to attach to surfaces as well as to each other?
Pilli
Which of these cell structures within the bacterial cytoplasm is(are) not visible via an electron microscope?
Plasmids
Function of nucleus
Protection, organization, replication, and expression of the genetic material.
Function fo Cytoskeleton
Provide shape to the cell and aid in movement.
The internal environment of droplet organelles differs chemically from that of the surrounding medium. This may affect processes such as: 'RNA folding DNA denaturation sugar catabolism protein maturation
RNA folding
Cytosol
Region of a eukaryotic cell that is outside the membrane-bound organelles but inside the plasma membrane
What structure functions in polypeptide synthesis?
Ribosome
Cell Wall
Rigid and porous structure. Contains mostly peptides and carbs.
Cilia
Shorter than flagella and tend to cover all or part of the surface of a cell. Produce movement similarly to flagella
Lysosomes
Small organelles found in animal cells.
Vesicles
Small, membrane-enclosed sphere by which other organelles of the endomembrane system pass materials to each other
Golgi apparatus
Stack of flattened membranes, each of which encloses a cisterna
Metabolism
Sum of the chemical reactions by which cells produce the materials and utilize the energy necessary to sustain life
Anabolism
Synthesis of molecules and macromolecules
Cytoskeleton
System of protein filaments. Composed of microtubules, microfilaments, and intermediate filaments.
Endoplasmic Reticulum
The endoplasmic reticulum is composed of a network of flattened tubules called cisternae that enclose a continuous ER lumen
Compartmentalization
Feature of eukaryotes; membrane-bound organelles that separate the interior of the cell into different regions
Nuclear pores
Formed where the inner and outer nuclear membranes make contact with each other. Nuclear pore complexes provide a passageway for the movement of molecules and macromolecules into and out of the nucleus.
Function of Peroxisomes
Function: 1. Catalyze variety of chemical reactions including reactions that break down organic molecules and others.
Function of Smooth ER
Function: 1. Metabolism 2. Storage of Ca2+ 3. Lipid synthesis and modification
Function of Rough ER
Function: 1. Protein sorting 2. Insertion of membrane proteins 3. Glycosylation
Function of Vacuoles
Function: 1. Stores large amount of water, enzymes, and inorganic ions. 2. Space filler - exerts pressure on the cell wall called turgor pressure which maintains the structure of the cell. 3. Degradation.
Function of Lysosomes
Function: Break down molecules with hydrolytic enzymes that use water to break a covalent bond (hydrolysis)
Function of Mitochondria
Function: 1. Primary role is to generate ATP convert chemical energy from organic molecules into form that can be used by cells. 2. Contributes in synthesis, medication, and breakdown of cellular molecules.
Function of Golgi apparatus
Function: Responsible for protein sorting, processing through glycosylation or proteolysis, and secretion
Which of the following organisms are eukaryotes? Fungi Bacteria Animals Plants Archaea
Fungi Animals Plants
Pili
Hairlike projections that allow cells to attach to surfaces and to each other
Motor Protein domains
Head: the site where ATP binds and is hydrolyzed to adenosine diphosphate (ADP) and inorganic phosphate (Pi) Hinge: the site that bends in response to ATP binding and hydrolysis. This bending is what causes movement to occur. Tail: an elongated region that is attached to other proteins or to other kinds of cellular molecules
Differential Gene Regulation
Every cell expresses a unique set of mRNAs. These mRNAs are then translated to produce a specific set of polypeptides that form proteins
Mitochondria
Enclosed in double membrane. Appears threadlike or granular shaped. Similar to bacteria in size. Contains an inner and outer membrane separated by intermembrane space. Forms cristae in inner membrane.
Chloroplasts
Enclosed in double membrane. Has a thylakoid membrane system so it forms flattened compartments, stack on each other to form grana. Green pigment.
What cells have membrane-bound organelles to compartmentalize functions? Neither prokaryotic nor eukaryotic cells Both prokaryotic and eukaryotic cells Prokaryotic cells only Eukaryotic cells only
Eukaryotic cells only
