Chapter 4 Biology
transport vesicles
membranous spheres that bud from the rough ER
The fluid mosaic model of the plasma membrane is characterized by ________.
molecules moving freely past one another
The endosymbiont theory states that chloroplasts and mitochondria were previously
free-living prokaryotes
Ribosomes function
produce membrane proteins and secretory proteins
What is the smallest entity that exhibits all the characteristics of life?
Cells
Which cells contain membrane bound organelles?
Eukaryotic
Which carbon compound is composed of CH2O?
carbohydrate
How does DNA direct protein production?
1) DNA programs protein production in the cytoplasm by transferring its coded info to mRNA, which carries the order to the cytoplasm 2). it exits the nucleus through pores and attaches onto ribosome 3) ribosome moves along mRNA, and translates the genetic code to a protein
endomembrane system
A network of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles. (nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles)
Compare the structure and function of chloroplasts and mitochondria. Describe the adaptive advantages of extensive folds in the grana of chloroplasts and the inner membrane of mitochondria.
Chloroplasts are plant organelles that perform photosynthesis (light energy --> chemical energy of sugars). They contain stacked discs called grana and tubes to perform photosynthesis. More grana folds --> more surface area --> more output. Mitochondria are the organelles of cellular respiration and produce ATP from the energy of food molecules. There are numerous infoldings called cristae in the inner membrane. More cristae folds --> more surface area --> more output.
The term used to indicate the part of a eukaryotic cell where organelles are suspended in fluid is _________
Cytoplasm
Explain how the genetic information in the nucleus is used to direct the production of proteins in the cytoplasm.
DNA-containing genes in the nucleus programs protein production in the cytoplasm by transferring its coded information into messenger RNA. Messenger RNA then exits the nucleus through pores in the nuclear envelope. Ribosomes and the mRNA work together to translate genetic messages into different proteins. so pretty much: Nucleus ---> mRNA ----> ribosome
A major difference between prokaryotic and eukaryotic cells is that __________
Eukaryotic cells have organelles; prokaryotic cells do not
matrix
Innermost compartment of the mitochondrion, thick fluid
Compare the following pairs of terms, noting the most significant differences: light microscopes vs. electron microscopes, scanning electron microscopes vs. transmission electron microscopes, magnification vs. resolution, prokaryotic cells vs. eukaryotic cells, plant cells vs. animal cells.
Light microscopes solely use light that passes through the specimen and use lenses to enlarge the image while electron microscopes use beams of electrons to better resolve images. Scanning electron microscopes are used to examine cell surfaces and transmission electron microscopes are used to study the internal structure of cells. Magnification is an increase in the object's image size compared to its actual size while resolving power is the ability of an optical instrument to show two objects as separate. Plant cells distinctly contain a cell wall, chloroplasts, and a central vacuole while animal cells distinctly contain lysosomes and centrioles.
Which of the following are the two main components of cellular membrane?
Proteins and phospholipids
Compare the structures and functions of a plant cell wall and the extracellular matrix of an animal cell.
Rigid plant cell walls are made of cellulose to protect, maintain shape, and regulate water absorption of the cell. Animal cells lack cell walls and usually contain extracellular matrices to protect, support, and hold cells together in tissues. This helps animals to move around in contrast to plant cells (which is why animals can dance and plants can't)
Most antibiotics kill invading bacteria while minimally harming the host by _________?
Targeting structures found only in bacterial cells and not the host cells
Describe the functions of the cytoskeleton. Compare the structures and functions of cilia and flagella.
The cytoskeleton is a network of fibers/filaments throughout the cytoplasm. These fibers, such as microtubules give the cell anchorage shape. The cytoskeleton is EXTREMELY dynamic by moving around and is constantly reassembled.Cilia and flagella both have the same basic structure as appendages extending from the outside of cells, and they both help move cells (or move fluid over cells). However, cilia are short and numerous and move in a back-and-forth movement, while flagella are long, singly-occurring, and whip back and forth.
extracellular matrix
The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.
Describe the structure of the plasma membrane and other membranes of the cell. Explain why this structure is called a fluid mosaic.
The thin plasma and other membranes of cells are composed of mostly phospholipids (which form a double-layered bilayer) and proteins. It is fluid because molecules can move freely past one another and a mosaic because of the diversity of proteins in the membrane
explain how each word in the term fluid mosaic describes the structure of a membrane
a membrane is fluid, and it is diverse of embedded proteins
cytoskeleton
a network if fibers extending throughout cytoplasm, helps with support and movement. Nucleus is often held in place by a cytoskeletal cage of filaments. Cytoskeleton can quickly dismantle in one part of the cell by removing proteins submits and re-form in a new location
phospholipid bilayer
a two-layered membrane
microtubules
a type of fiber and are straight, hollow tubes composed of proteins
match the following organelles with their functions: a. ribosomes b. microtubules c. mitochondria d. chloroplasts e. lysosomes 1. movement 2. photosynthesis 3. protein synthesis 4. digestion 5. cellular respiration
a3, b1, c5, d2, e4
using a light microscope to examine a thin section of a large spherical cell, you find that the cell is 0.3 mm in diameter. The nucleus in micrometers?
about 0.075 mm
central vacuole (plant only)
accounts for more than half the volume of a mature plant cell, stores organic nutrients, and absorbs water (allowing cells to expand, and can contain poisons to protect against plant-eaters)
you look into a light microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?
b.
Which one of the following groups is composed of prokaryotic cells?
bacteria
eukaryotic cells
belong to the Eukarya domain
A plant cell has a versatile compartment that stores organic nutrients, absorbs water, and contains poisons that protect against plant-eating animals. This compartment is the _________.
central vacuole
prokaryotic cells
characterize organisms of domains Bacteria & Archaea
Within the nucleus of a cell, long DNA molecules and associated proteins form fibers called ____________.
chromatin
The function of the chloroplast is to ___________.
convert light energy to chemical energy
plant cell only: chloroplast
convert light energy to the chemical energy of food
cilia and flagella structure
core of microtubules wrapped in extension of plasma membrane
if you wanted to film the movement of chromosomes during cell division, the best choice for a microscope would be a
d
When a protein unfolds due to changes in pH, temperature, or salinity, the protein is said to
denature and lose function
Which of the following is stored in the lysosomes of the cell?
digestive enzymes
You're convinced that a sample you have is a carbohydrate. However, it tests negative with both iodine and Benedict's solution. What type of carb is it likely to be?
disaccharide
smooth ER
doesn't have ribosomes
chromosome
each long chromatin fiber has one chromosome
identify which one of the following structures includes all the others in the list: rough ER, smooth ER, endomembrane system, the Golgi apparatus.
endomebrane system
The nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles make up the _______________.
endomembrane system
what is the most significant structural difference between prokaryotic and eukaryotic cells?
eukaryotic cells have organelles
Describe the parts of the cell theory
everything is made from cells, and cells come from cells
Robert Hooke
first to observe "small chambers" in cork and call them cells.
chromatin
formed by long DNA molecules within the nucleus & associated proteins
importance of lysosomes
hereditary disorders (lysosomal storage diseases) are missing 1+ digestive enzymes in the lysosomes, and the lysosomes are unable to. break down certain proteins, and these diseases can be fatal in childhood
Nucleic acids can be broken down by _______ reactions to the monomers known as ______.
hydrolysis, nucleotides
cristae
inner membrane of mitochondria, numerous foldings
flagella
long projections that propel bacteria through a liquid environment, whiplike motion
Which organelles function in the endomembrane system?
lysosomes, Golgi apparatus, smooth & rough ER
ribosome transport (eukaryote)
made in nucleus, then transported through pores of nucleus into cytoplasm, where some ribosomes work, and others attach to ER
Endoplasmic Reticulum
main manufacturing facility within a cell, produces a lot of molecules. The ER is connected to the nuclear envelope, and it forms a labyrinth of tubes and sacs that run through the cytoplasm. Two parts of the ER: rough ER & smooth ER (connected but differ in structure)
Rough endoplasmic reticulum appears "rough" because _________________.
many ribosomes stud the outside of the ER membrane
organelles
membrane-enclosed structures that perform specific functions
Coded genetic information is produced in the nucleus and transferred to the cytoplasm in a molecule called _________.
messenger RNA
In addition to the nucleus, which of the following are organelles that contain DNA?
mitochondria and chloroplasts
Which organelles are involved in energy transformations?
mitochondria, chloroplast
cilia
more numerous than flagella and promote movement and they go back in forth
nucleus (EUKARYOTE only)
most important organelle, houses most of a eukaryotic cell's DNA, surrounded by double membrane
Golgi apparatus
named after its discoverer (Camillo Golgi). Function: refinery, warehouse, and shipping center. Works in close partnership w/ ER, it receives, refines, stories, and distributes chemical products of the cell. It receives stuff from the ER in transports vesicle (one side of Golgi is a receiving dock for vesicles and the other side is the shipping side for finished products (for other organelles or even outside the cell)).
DNA controls the cell by transmitting genetic messages that result in protein production. Place the following organelles in the order that represents the flow of genetic information from the DNA through the cell: nuclear pores, ribosomes, nucleus, rough ER, Golgi apparatus
nucleus, nuclear pores, ribosomes, rough ER, Golgi
chloroplast
organelles that perform photosynthesis, partitioned into 3 compartments by internal membranes: space between 2 membranes, stroma, grana
Mitochondria, the sites of cellular respiration, are found in _________.
plant cells and animal cells
Which of these distinguishes a plant cell from an animal cell?
presence of a cell wall
The sequence of amino acids refers to what level of protein structure?
primary
which type of cell is older?
prokaryotic
which type of cell is simpler?
prokaryotic
nucleolus
prominent structure within the nucleus, site where components of ribosomes are made
The Golgi apparatus mainly functions to modify __________.
proteins
Rough ER
refers to the appearance of the organelle, roughness is due to ribosomes on the outside of ER membrane. Functions: produce new membrane. Cells that need to secrete a lot of protein (like saliva glands) are rich in rough ER. Some products made by the rough ER are dispatched to other organelles use transport vesicles to do so
plasma membrane
regulates the traffic of molecules between cell & surroundings (ALL cells)
ribosomes (basic)
responsible for protein synthesis
What are the primary sites of protein production in a eukaryotic cell?
ribosomes
you can track the path of a protein within the cell from production through export by labeling them with radioactive isotopes. identify which of the following structures would be labeled in your experiment, in order: chloroplasts, Golgi, plasma membrane, smooth ER, rough ER, nucleus, mitochondria
rough ER, Golgi, plasma membrane
Compare the structures and functions of the following components of the endomembrane system: rough endoplasmic reticulum, smooth endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles.
rough ER: synthesize proteins smooth ER: synthesize lipids/ detoxify Golgi: shipping and handling Lysosomes: digestion Vacuoles: storage facility
lysosomes
sac of digestive enzymes found mostly only in animal cells, developed from vesicles that come off the Golgi. The enzymes within a lysosome can break down macromolecules. Some nutrients go to food vacuoles, and any small molecules that result, leave the lysosome and nourish the cell. Lysosomes also destroy harmful bacteria, and they also break down the large molecules of damaged organelles so the molecules are available to make a new organelle. They also help in embryonic development (digest webbing between fingers).
vacuoles
sacs that bud from the ER, Golgi, or plasma membrane. (come in lots of sizes and functions)
name two similarities in the structure/function of chloroplasts and mitochondria. Name two differences.
similar: energy, originated from prokaryotes differences: chloroplasts are only in plant cells, chloroplasts have 3 compartments
mitochondria
sites of cellular respiration, harvests energy from sugars and converts it to ATP, cells then use molecules of ATP as the direct energy source. Found in all. eukaryotic cells, envelop of 2 membrane encloses mitochondrion
the ER has to distinct regions that differ in structure and function. Lipids are synthesized within the ______, and proteins are synthesized within the _____
smooth ER, rough ER
capsule
some prokaryotes have this structure surrounding the cell wall for extra protection
1st compartment
space between 2 membranes that envelop the chloroplast
cell junctions
structures that connect to other cells (animal cells)
smooth ER functions
synthesis of lipids (sex hormones are enriched with smooth ER), detoxify stuff in the liver, can increase tolerance of drugs (kinda causes addiction)
cytoplasm
the entire region of the cell between the nucleus and plasma membrane
grana
the interior of a network of membrane-enclosed disks and tubes, solar power packs, trap light energy and convert it to chemical energy
phospholipids
the lipids surrounding the plasma membrane (only have 2 fatty acids, and a phosphate group, which is electrically charged, making it hydrophilic)
fluid mosaic
the molecules can float freely and are very diverse
What is the genetic center of the eukaryotic cell?
the nucleus
nuclear envelope
the nucleus is bordered by a. double membrane, similar in structure to plasma membrane
explain how antibiotics specifically target bacteria while minimally harming the human host.
they focus on killing the part of the bacterial cell that doesn't exist in an eukaryote cell.
stroma
thick fluid within the chloroplast
food vacuoles
tiny cytoplasmic sacs that many cells engulf nutrients into
ribosomes
tiny structures that build proteins according to instructions from DNA (ALL cells)
Which of the following correctly matches the organelle with its function?
vacuole ---> storage