Chapter 3 Cells

Enzymes in the lysosomes function at a more ______ pH than the cytoplasm, which means the enzymes only function within the enclosed lysosome, unless all of a cell's lysosomes burst at once.

Acidic

Cytoplasm

All cell contents except the nucleus

Select all of the following ideas that were added to the cell theory in modern times.

All cells contain DNA, which is duplicated and passed to new cells when the cell divides. All cells use energy to accomplish cell processes.

Spiral or corkscrew, round, and rod-shaped are all common shapes of

Bacteria

Enzymes in the Golgi apparatus can synthesize and attach ______ to proteins and lipids, forming glycoproteins and glycolipids.

Carbohydrates

In bacterial cells, the nucleoid is where the cell's ______ congregates.

DNA

Select all of the following that are present in bacterial cells.

DNA enzymes ribosomes cytoplasm

Select the true statement describing how DNA in the nucleus is used to specify protein production by the cell.

DNA is copied into mRNA in the nucleus, and the mRNA is used outside the nucleus to make proteins.

In a cell, ______ is the genetic information of the cell, and RNA plays a role in the production of ______.

DNA; proteins

Select all of the following that are true about organisms in Domain Bacteria.

Earth's oldest organisms important decomposers and producers some are used to make pharmaceuticals some live in human intestines and help with digestion

What type of membrane protein speeds up chemical reactions?

Enzymes

Domain Archaea is more closely related to domain ______ than to the prokaryotic domain, ______.

Eukarya; Bacteria

Lysosomes originate from vesicles that bud from the ______, and the enzymes contained in lysosomes are synthesized in the ______.

Golgi apparatus; rough ER

What English physicist first observed the outlines of cells when he looked at cork from an oak tree?

Hooke

Cytoskeletal components called____ filaments are made of different proteins depending upon the cell type and help to maintain cell shape and bind some cells together.

Intermediate

The ______ microscope is ideal for viewing living cells that are between 200 nanometers and 1 millimeter in size.

Light

Cell membrane

Lipid-rich boundary between the cells and outside enviroment

Cellular respiration extracts energy from food and takes place in the organelle called a

Mitochondria

Select all of the following that are able to pass freely through the phospholipid bilayer.

O2 and CO2 small nonpolar molecules lipids

All cells are surrounded by cell membranes, also called plasma membranes, that separate the cytoplasm from the

Outside enviroment

Select all of the following that are examples in which the ratio of surface area to volume of cells is increased.

Paramecia are horizontally flattened in shape. Amoebas have extensions of their cell membrane. Nerve cells are long and thin.

______ are a category of plant organelles that contain their own DNA and ribosomes and can convert to many functions.

Plastids

______ cells are the simplest forms of life and lack a nucleus.

Prokaryotic

German biologists Schleiden and Schwann were the first to

Propose the Cell theory

proteins bind to molecules and ions on the outside of the cell, triggering a reaction on the inside of the cell.

Receptor

Proteins to be secreted outside of a eukaryotic cell are formed at ribosomes on the surface of the ______ endoplasmic reticulum.

Rough

the three scientists that proposed the three components of the cell theory in the mid-1800s.

Schleiden Schwann Virchow

Select all of the following that correctly describe plant organelles called plastids.

Some assemble and store starch. They contain their own DNA and ribosomes. Some, such as chloroplasts, synthesize pigments.

lect the three components of the cell theory devised in the mid-1800s.

The cell is the fundamental unit of all life. All organisms are made of one or more cells. All cells originate from preexisting cells.

Dna

The cells genetic information

Why are ions and polar molecules unable to pass directly through a cell membrane?

The interior of the phospholipid bilayer is hydrophobic.

______ are flattened membrane sacs within a chloroplast where photosynthetic pigments, such as chlorophyll, are embedded.

Thylakoids

proteins are embedded in the cell membrane and act as passageways for water-soluble materials into or out of the cell.

Transport

Plant cells have large central ______ where water, salts, and sugars are stored and where materials are broken down and recycled with enzymes similar to lysosomes in animal cells.

Vacuoles

A eukaryotic cell is different from a prokaryotic cell in that it contains

a nucleus.

What type of prokaryotes are most closely related to eukaryotes?

archaea

Select all of the following that correctly describe Archaean cells.

can have flagella lack nuclei and organelles most have cell walls

In bacterial cells, what is the function of flagella?

cell movement

What surrounds the cell membrane of most bacteria and provides structure and protection?

cell wall

What cell shape has the most efficient exchange of materials between the cell's interior and exterior?

cell with more surface area relative to volume

What plant cell organelle can occupy up to 90% of the cell volume and can exert turgor pressure against the cell membrane when it acquires water?

central vacuole

Each centrosome in animal cells contains two ______, which form basal bodies of flagella and cilia and spindle fibers of chromosomal division.

centrioles

In animal cells, structures called ______ are microtubule-organizing centers that contain the centrioles.

centrosomes

Gap Junctions

channels for the exchange of substances between adjacent animal cells

Select all the organelles that are thought to have arisen by endosymbiosis.

chloroplasts mitochondria

Short, numerous, hairlike structures that surround some cells like a fringe, are powered by microtubules, and have coordinated movements are called

cilia

Some protists, like Paramecium, are able to move through a watery environment with thousands of short extensions on the cell called

cilia

anchoring junctions

connect animal cells to the extracellular matrix or to adjacent animal cells in one place gap junctions matches

Select all of the following that are true about lysosomes.

contain enzymes tagged with sugars enzymes inside the lysosome perform hydrolysis reactions can fuse with vesicle carrying debris from outside the cell or damaged organelles

The folds of the inner membrane of a mitochondrion, called ______, contain the enzymes for cellular respiration.

cristae

The ______ includes all of the cell contents between the nucleus and the cell membrane.

cytoplasm

The two-layered nuclear envelope separates the nucleus of a cell from the

cytoplasm

What is the network of protein fibers and tubules inside the cell that provides support and aids in cell division and movement?

cytoskeleton

Select all of the following that are components of the cytoplasm, outside the nuclear membrane.

cytoskeleton organelles ions and enzymes cytosol

The fluid part of the cell cytoplasm is called

cytosol

What type of microscope allows resolution of objects that are about 5 nanometers in size?

electron

The internal membranes of several organelles are interconnected and form the ______ system of a eukaryotic cell.

endomembrane

Select all of the cell parts that are involved in the endomembrane system.

endoplasmic reticulum lysosomes nuclear envelope vacuoles Golgi apparatus

What theory describes how ancient organisms engulfed bacterial cells and, instead of being digested, the bacterial cells became organelles within the host cells?

endosymbiosis

Cells that contain membrane-bounded organelles and a nucleus are called

eukaryotic cells.

Select all of the following that differ between domains Bacteria and Archaea.

evolutionary relationship to eukaryotes chemical composition of flagella molecules that compose the cell membranes

In some types of bacteria, appendages called ______ rotate like a propeller and allow movement forward or backward.

flagella

Select all of the following that describe intermediate filaments of the cytoskeleton.

form an internal scaffold in the cytosol have a diameter of 10 nanometers

tight junctions

fuse cell membranes of adjacent animal cells, forming a barrier

Select all of the functions of the bacterial cell wall.

give the cell its shape protect the cell prevent the cell from bursting

Select all of the following that describe microfilaments of the cytoskeleton.

help anchor cells to each other composed of the protein actin function in cell contraction and compression

Select all of the following that describe tight junctions.

join adjacent cells into sheets membrane proteins connect to actin in the cytoskeletons of adjacent cells create the "blood-brain barrier"

Select all of the following that are functions of lysosomes.

lyse captured bacteria dismantle worm-out organelles breakdown large food particles into smaller subunits

What organelle of the endomembrane system breaks down debris, food, and old cell parts with special dismantling enzymes?

lysosome

Organelles carry out specialized functions in the cell and are enclosed by

membranes

Select all of the following that are true about prokaryotes.

most ancient forms of life on Earth simplest types of life lack a nucleus

What structures allow the passage of regulatory proteins into the nucleus and mRNA molecules out of the nucleus?

nuclear pores

In prokaryotic cells, DNA congregates in an area called the

nucleoid

Select all of the characteristics of eukaryotic cells.

nucleus system of internal membranes larger than prokaryotic cells

Within the cytoplasm of eukaryotic cells, there are multiple specialized compartments called

organelles

The enzymes in one lysosome could not digest a cell because the ______ of the lysosome is much ______ than the neutral cytoplasm, and therefore the lysosome enzymes would not be able to function fully in the cell cytoplasm.

pH; more acidic

What organelle protects all eukaryotic cells from toxic substances or toxic by-products of chemical reactions?

peroxisome

In cell membranes, what part of a phospholipid molecule is oriented toward the outside of the bilayer?

phosphate head

Select all of the following that are found in chloroplasts.

photosynthetic pigments thylakoids DNA stroma ribosomes

Select all of the following that are true about eukaryotic flagella.

prominent in sperm cells contain microtubules anchored by basal body

What component of cell membranes functions in a diversity of roles, including recognition, transport, adhesion, and facilitating reactions?

proteins

Select all of the following that are able to move laterally within the cell membrane, giving it the description of a fluid mosaic.

proteins phospholipids

Select all of the following that are components of cell membranes.

proteins phospholipids steroids

Select all the roles that membranes play in cells.

receive and respond to external stimuli enclose organelles in eukaryotic cells transport substances into and out of the cell

What type of cell membrane protein binds molecules on the cell's exterior, which triggers a reaction in the cell's interior?

receptor proteins

What cell structure binds to mRNA coming from the nucleus and manufactures proteins?

ribosome

The nucleolus is a dense spot in the nucleus where components of ______ are assembled.

ribosomes

Select the three common shapes of bacterial cells.

rod-shaped round spiral

Ribosome

structures that manufacture proteins

Select all of the characteristics of organelles.

studded with membrane proteins surrounded by membranes contain distinct proteins

Select all of the functions of the smooth endoplasmic reticulum.

synthesize lipids house enzymes that detoxify drugs and poisons

What type of cell membrane protein allows molecules and ions to enter or exit the cell?

transport proteins

Select all of the following that are functions of the cytoskeleton in the cell.

transportation aid for cell division structural support

plasmodesmata

tunnels for the exchange of substances between adjacent plant cells

Select all of the following that describe electron microscopes.

usually require that specimen be killed provide greater magnification than light microscopes expensive to build and operate use beam of electrons instead of light

Membranous spheres that transport materials inside the cell as part of the endomembrane system are called

vesicles

Membrane proteins synthesized in the ER are transported in ______ to the ______, where the proteins will complete their folding and be packaged for export to the cell membrane.

vesicles; Golgi apparatus

Turgor pressure in plant cells results from the expansion of the central vacuole as it fills with

water

Select all of the following that are present at the connection between normal cells of multicellular organisms.

ways that cells can communicate with each other a way for cells to adhere to one another

Select types of cells that have relatively more lysosomes.

white blood cells liver cells