CCBC BIO 110 Exam 2 Questions with
Accurate Answers
Cell theory proposed by Mathias Schleiden and Theodore Schwann: - ANSWERS• All
organisms are made of cells
• The cell is the simplest collection of matter that can be alive
• All cells are related by their descent from earlier cells
• Cells can differ substantially from one another but share common features
Limits to cell size: - ANSWERS• Cells are usually too small to be seen by the naked
eye. Microscopes are used to visualize cells.
• Metabolic requirements set upper limits on the size of cells. The surface area to
volume ratio of
a cell is critical. As a cell increases in size, its volume grows proportionately more than
its surface
area.
• The plasma membrane is a selective barrier that allows sufficient passage of oxygen,
nutrients,
and waste to service the volume of every cell.
Prokaryotic cells have: - ANSWERS• No nucleus.
• DNA in an unbound region called the nucleoid.
• No membrane-bound organelles.
• Cytoplasm bound by the plasma membrane
Eukaryotic cells are characterized by having: - ANSWERS• DNA in a nucleus that is
bounded by a membranous nuclear envelope.
• Membrane-bound organelles.
• Cytoplasm in the region between the plasma membrane and nucleus.
• Eukaryotic cells are generally much larger than prokaryotic cells.
The eukaryotic cell's genetic instructions are - ANSWERShoused in the nucleus and
carried out by the ribosomes
The nucleus - ANSWERScontains most of the cell's genes and is usually the most
conspicuous organelle
The nuclear envelope - ANSWERSencloses the nucleus, separating it from the
cytoplasm. The nuclear
membrane is a double membrane; each membrane consists of a phospholipid bilayer.
, In the nucleus, DNA is organized into discrete units called - ANSWERSchromosomes.
Each chromosome is
composed of a single DNA molecule associated with proteins.
The DNA and proteins of chromosomes are together called - ANSWERSchromatin.
Chromatin condenses to
form discrete chromosomes as a cell prepares to divide.
The nucleolus is - ANSWERSlocated within the nucleus and is the site of ribosomal
RNA (rRNA) synthesis.
Ribosomes - ANSWERSare complexes made of ribosomal RNA and protein.
Ribosomes carry out protein: synthesis in two locations - ANSWERS• In the cytosol
(free ribosomes)
• On the outside of the endoplasmic reticulum or the nuclear envelope (bound
ribosomes)
The endomembrane system - ANSWERSregulates protein traffic and performs
metabolic functions in the cell.
The endomembrane system consists of: - ANSWERS• Nuclear envelope
• Endoplasmic reticulum
• Golgi apparatus
• Lysosomes
• Vacuoles
• Plasma membrane
These components are either continuous or connected via transfer by vesicles.
The endoplasmic reticulum (ER) - ANSWERSaccounts for more than half of the total
membrane in many eukaryotic cells. The ER membrane is continuous with the nuclear
envelope.
There are two distinct regions of ER: - ANSWERSSmooth ER and Rough ER
Smooth ER, which lacks ribosomes: - ANSWERS• Synthesizes lipids
• Metabolizes carbohydrates
• Detoxifies drugs and poisons
• Stores calcium ions
Rough ER, whose surface is studded with ribosomes: - ANSWERS• Has bound
ribosomes, which synthesize membrane proteins, lysosomal proteins and proteins
destined for secretion
• Protein quality control.
• Distributes transport vesicles, secretory proteins surrounded by membranes.
Accurate Answers
Cell theory proposed by Mathias Schleiden and Theodore Schwann: - ANSWERS• All
organisms are made of cells
• The cell is the simplest collection of matter that can be alive
• All cells are related by their descent from earlier cells
• Cells can differ substantially from one another but share common features
Limits to cell size: - ANSWERS• Cells are usually too small to be seen by the naked
eye. Microscopes are used to visualize cells.
• Metabolic requirements set upper limits on the size of cells. The surface area to
volume ratio of
a cell is critical. As a cell increases in size, its volume grows proportionately more than
its surface
area.
• The plasma membrane is a selective barrier that allows sufficient passage of oxygen,
nutrients,
and waste to service the volume of every cell.
Prokaryotic cells have: - ANSWERS• No nucleus.
• DNA in an unbound region called the nucleoid.
• No membrane-bound organelles.
• Cytoplasm bound by the plasma membrane
Eukaryotic cells are characterized by having: - ANSWERS• DNA in a nucleus that is
bounded by a membranous nuclear envelope.
• Membrane-bound organelles.
• Cytoplasm in the region between the plasma membrane and nucleus.
• Eukaryotic cells are generally much larger than prokaryotic cells.
The eukaryotic cell's genetic instructions are - ANSWERShoused in the nucleus and
carried out by the ribosomes
The nucleus - ANSWERScontains most of the cell's genes and is usually the most
conspicuous organelle
The nuclear envelope - ANSWERSencloses the nucleus, separating it from the
cytoplasm. The nuclear
membrane is a double membrane; each membrane consists of a phospholipid bilayer.
, In the nucleus, DNA is organized into discrete units called - ANSWERSchromosomes.
Each chromosome is
composed of a single DNA molecule associated with proteins.
The DNA and proteins of chromosomes are together called - ANSWERSchromatin.
Chromatin condenses to
form discrete chromosomes as a cell prepares to divide.
The nucleolus is - ANSWERSlocated within the nucleus and is the site of ribosomal
RNA (rRNA) synthesis.
Ribosomes - ANSWERSare complexes made of ribosomal RNA and protein.
Ribosomes carry out protein: synthesis in two locations - ANSWERS• In the cytosol
(free ribosomes)
• On the outside of the endoplasmic reticulum or the nuclear envelope (bound
ribosomes)
The endomembrane system - ANSWERSregulates protein traffic and performs
metabolic functions in the cell.
The endomembrane system consists of: - ANSWERS• Nuclear envelope
• Endoplasmic reticulum
• Golgi apparatus
• Lysosomes
• Vacuoles
• Plasma membrane
These components are either continuous or connected via transfer by vesicles.
The endoplasmic reticulum (ER) - ANSWERSaccounts for more than half of the total
membrane in many eukaryotic cells. The ER membrane is continuous with the nuclear
envelope.
There are two distinct regions of ER: - ANSWERSSmooth ER and Rough ER
Smooth ER, which lacks ribosomes: - ANSWERS• Synthesizes lipids
• Metabolizes carbohydrates
• Detoxifies drugs and poisons
• Stores calcium ions
Rough ER, whose surface is studded with ribosomes: - ANSWERS• Has bound
ribosomes, which synthesize membrane proteins, lysosomal proteins and proteins
destined for secretion
• Protein quality control.
• Distributes transport vesicles, secretory proteins surrounded by membranes.
