BIOL Pre-Lecture Chapter 3
______ cells are the simplest forms of life and lack a nucleus.
Prokaryotic
Select 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.
Select all of the following that differ between domains Bacteria and Archaea.
evolutionary relationship to eukaryotes molecules that compose the membranes
The cell membrane can be described as a(n) ________ mosaic because many of the diverse components can move freely within the cell membrane.
fluid
The phosphate "head" end of a phospholipid is ______, meaning its polar covalent bonds attract water, but the tails of a phospholipid are ______ and thus face away from water.
hydrophilic; hydrophobic
In eukaryotic cells, the DNA that codes for the cell's proteins is stored in a membrane-bounded organelle called the
nucleus
What is the most ancient type of life on Earth?
prokaryotes
Select a component of the cell membrane that is able to move laterally within the membrane, giving it the description of a fluid mosaic.
proteins
The nucleolus is a dense spot in the nucleus where components of ______ are assembled.
ribosomes
Select all of the following that are able to pass freely through the phospholipid bilayer without the assistance of transport proteins.
small nonpolar molecules lipids O2 and CO2
Molecules called ______, which include cholesterol, are membrane components that aid in membrane fluidity.
steroids
Select all of the following that may be components of cell membranes.
steroids phospholipids proteins
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 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
Key genetic sequences suggest that archaea are more closely related to members of domain ______ than they are to members of Domain Bacteria.
Eukarya
Protists, plants, fungi, and animals are organisms in the domain ______.
Eukarya
Select all of the following that are present in both prokaryotic cells and eukaryotic cells.
RNA ribosomes DNA cytoplasm
Domain Eukarya includes ______.
all organisms with eukaryotic cells
Select all of the following that correctly describe Archaean cells.
can have flagella most have cell walls lack nuclei and organelles
All living things consist of one or more ______
cell
The _________ theory states that all life is composed of one or more cells, which are the fundamental units of all life.
cell
The rigid ______ of most bacterial cells surrounds the cell membrane, protecting the cell and giving the cell shape.
cell wall
What surrounds the cell membrane of most bacteria and provides structure and protection?
cell wall
The ___________ theory states that all life is composed of one or more cells, which are the fundamental units of all life.
cell, cellular, early cell, or unified cell
All living things consist of one or more ________
cells
Whether bacterium or blue whale, every organism is made of
cells
The portion of the phospholipid bilayer indicated by the circle in the picture is ______.
hydrophobic
What type of microscope passes light through a transparent specimen to generate true-color views of cells?
light microscope
All cells have a cell ______ that surrounds the cytoplasm and forms a boundary between the cell and its environment.
membrane
Select all of the following that correctly describe Archaean cells.
most have cell walls can have flagella lack nuclei and organelles
The ______ found within the nuclear envelope are specialized channels that are composed of proteins and that allow the transport of substances into and out of the nucleus.
nuclear pores
All cells are surrounded by cell membranes, also called plasma membranes, that separate the cytoplasm from the
outside environment
Biological membranes are selectively ______, meaning they allow only specific types of molecules to pass into or out of the cell.
permeable
The cell membrane is composed of a type of lipid molecule called a(n) ______, which has two fatty acids and a phosphate group extending from a glycerol molecule.
phospholipid
The cell structure that manufactures proteins is called a
ribosome
______ microscopes bounce electrons off the outside of a metal-coated three-dimensional object to observe the exterior texture
scanning electron
Archaea are
single-celled prokaryotes.
Select all of the following that are true about organisms in Domain Bacteria.
some are used to make pharmaceuticals important decomposers and producers some live in human intestines and help with digestion Earth's oldest organisms
______ proteins are embedded in the cell membrane and act as passageways for water-soluble materials into or out of the cell.
transport
Select all the roles that membranes play in cells.
transport substances into and out of the cell enclose organelles in eukaryotic cells receive and respond to external stimuli
True or false: Bacteria are the most abundant and diverse organisms.
true
Membranous spheres that transport materials inside the cell as part of the endomembrane system are called
vesicles.
