Chapter 6 Flashcards
What is a light microscope (LM)?
lenses bend light to magnify images of specimens
What is an electron microscope (EM)?
uses magnets to focus an electron beam on or through specimen
How many times greater is the magnification of the EM compared to the LM?
100 times greater
What is a TEM microscope used to study?
the internal structure of thin section of cells
What is a SEM microscope used to study?
fine details of cell surface
What is magnification?
the ratio of an objects image size to its real size
What is resolution?
the measure of the clarity of the image
What is contrast?
the difference in brightness between light and dark areas
Staining is a method used to increase what?
contrast
What is cell fractionation?
taking apart a cell and diving it into it sub cellular parts (organelles)
What device is used in cell fractionation?
centrifuge
What are the two types of cells?
Prokaryotic and eukaryotic
What are the 2 sub groups of prokaryotes?
archea and bacteria
What are the 4 subgroups of eukaryotes?
anamilia
plantae
fungi
protists
Where is DNA concentrated in prokaryotic cells?
an area called the nucleiod
Where is DNA concentrated in eukaryotic cells?
the nucleus
Do prokaryotic cells have cell membranes?
yes
Do prokaryotic cells have cytosol?
yes
Do prokaryotic cells have nuclear membranes?
no
Do prokaryotic cells have chromosomes?
yes
Do prokaryotic cells have organelles?
no
Do prokaryotic cells have ribosomes?
yes
T or F? Cellular metabolism sets the limit for the cells size
T
What surrounds the different regions of a prokaryotic cell?
proteins
Prokaryotic cells are usually smaller. T of F?
T
What is a plasma membrane?
selective barrier that allows passage of goods and waste in the cell
Cells that need more surface area will tend to have what cellular structure?
microvilli
Where are most the genes in a eukaryotic cell found?
in the nucleus
What encloses the nucleus?
The nuclear envelope
Does the nuclear envelope have a double membrane?
yes
What is a pore complex?
proteins around the nuclear envelope pores that regulates what can come in an out
What is the nuclear lamina?
a group of protein filaments that help maintain the shape of the nucleus
Nucleolus is found in dividing or non dividing cells?
non dividing
What is the nucleolus made of?
granules and fibers
Where is RNA produced?
the nucleolus
What are the two subunits of ribosomes?
RNA + proteins
what translates mRNAs message into primary structure of polypeptide?
ribosome
Cells with higher rates of protein synthesis have high or low concentrations of ribosomes?
high
What is the specific name for ribosomes found in the cytoplasm?
free ribosomes
What is the specific name for ribosomes found attached to the ER and nuclear membrane?
bound
Bound ribosomes always stay attached to either the ER or the nuclear membrane. T or F?
F, bound ribosomes are interchangeable with free ribosomes
Starting with the nuclear membrane and ending with the plasma membrane what are the organelle steps of the end-membrane?
- nuclear membrane
- ER
- Golgi apparatus
- Lysosome
- Vesicles and vacuoles
- Plasma membrane
What is the function of the endomembrane?
to synthesis proteins, transport proteins, metabolize and move lipids, and detox poisons
What are vesicles?
secs made of membrane that specialize in transport
What is the endoplasmic reticulum?
large network of membranes
What are the membrane tubules and sacs called of the ER?
asternae
What is the internal compartment of the ER called?
ER lumen
What are the functions of the smooth ER?
- synthesis of lipids
- metabolism of carbs
- detox of drugs and poisons
- storage of calcium ions
What functional group is added to drugs to make them easier to flush?
hydroxyl group
What are glycoproteins?
proteins with carbs covalently bonded
What is the specializes region that is responsible for vesicles budding from the ER?
transitional ER
What is the Golgi apparatus?
warehouse for receiving, sorting, and shipping
What are the flat membrane sacs of the Golgi apparatus called?
cisternae
What is the shipping side of the Golgi apparatus called?
transface
What is the receiving side of the Golgi apparatus called?
cisface
What are lysosomes?
membranous sacs that are often responsible for digestion
Lysosomal enzymes work best in basic, acidic, or nuetral environments
acidic
What is phagocytosis?
lysosomes digest materials
What is autophagy?
lysosomes recycle intracellular materials
What is a vacuole in general?
large vesicle
What are mitochondria?
site of cellular respiration
What are chloroplasts?
organelles responsible for photosynthesis
What is the Endosymbiotic Theory
the theory that mitochondria and chloroplasts oriented from prokaryotic cells that happened to be engulfed
Where is mitochondria DNA found?
the matrix
What are the layers of a mitochondria starting from the outside?
outermembrane, inner membrane space, the inner membrane, and the matrix
What are the folds of the mitochandria called?
cristae
Where are the enzymes for the citric acid cycle found?
in the matrix
Where are the small holes on the outside of the mitochondria called?
porins
Where is ATP synthase found?
in the inner membrane
Stacks of thylakoids are called what?
grana
What is the stroma?
Dense fluid within within the inner membrane
What is a granum?
A stack of membrane bounded thylakoids
What are lamella?
connector between grana
What are peroxisomes?
an organelle that carries enzymes to degrade material
What is glyoxysome
specialized peroxisome found in fat storing tissue of plant that helps initiate fatty acids being turned into sugar
What is the cytoskeleton?
A network of microtubules, microfilaments, intermediate filaments and proteins that extend throughout the cytoplasm
What are microtubules?
hollow rod composed of tubular proteins
What are flagella and cilia made of?
microtubules
What are microfilaments?
a cable like structure made of actin filaments
Which type of filament when acting with myosin causes cell contractions?
microfilaments
What are intermediate filaments?
fibrous proteins coiled into cables made out of keratin
Organize the different filaments by increasing size
micro, intermediate, microtubules
What is the subunit of microtubules?
alpha and beta tubulin dimers
What is the subunit of microfilaments?
actin
What type of filament do motor proteins “walk” on?
microtubules
What is a centrosome?
a pair of centrioles (made up of microtubules)
What do flagella specialize in?
locomotion
What do motile cilia specialize in?
locomotion and moving fluid past the cell
What do primary cilium specialize in?
sensory and signaling
What is the microtubule arrangement of flagella?
9 + 2
What is the microtubule arrangement of motile cilium?
9 + 2
What is the microtubule arrangement of primary cilium?
9 + 0
What are dyneins
the motor proteins of a microtubule
In the 9 + 2 arrangement how many tubulin are there per group in the outer circumference?
2
In the 9 + 0 arrangement how many tubulin are there per group in the outer circumference?
3
What is the basal body?
where the flagella is attached
What type of protein is actin?
globular
What is an actin filament?
twisted double chain of actin subunits
What do you call the microfilaments inside the plasma membrane?
cortical membrane
What is psuedopia?
a cellular extension involved in phagocytosis
Is the cytoplasm held in place like jelly?
no, moves around helping contents also move
What is the cell wall?
a protective layer external to the plasma membrane
What is the cell wall made of?
polysaccharides such as cellulose
What is a plasmodesmata?
an open channel through the cell wall that connects the cytoplasms of adjacent cells
What is the extracellular matrix?
the meshwork surrounding animal cells that consists of glycoproteins, polysaccharides, and proteoglycans
What is a fibronectin?
attaches to ECM to intergrins embedded in the plasma membrane
What are proteoglycan complexes?
hundreds of proteogycan molecules attached to single polysaccharide molecules
What are tight junctions?
plasma membranes of neighboring cells tightly pressed against each other
What are desmosomes?
rivets, hold cells together using anchors made of keratin protein and intermediate filaments
What are gap junctions?
channels between cells that selectively allow
What is a filopodium
the extension of microphage that engulfs the bacteria