Eukaryotic Cells
In eukaryotic cells, DNA replication takes place in the: 1. nucleus 2. cytoplasm 3. mitochondria
1 and 3: nucleus and mitochondria
At which pH level would a lysosome's enzyme function best? 1, 5, 7, or 9?
5- slightly acidic conditions
Which of the following is NOT a tenet of cell theory? A. all cells are capable of reproducing B. the cell is the basic unit of life C. all cells arise from preexisting cells D. all organisms are composed of one or more cells
A. all cells are capable of reproducing
Which of the following is a function of the rough endoplasmic reticulum? A. folding and modifying newly synthesized proteins B. Digesting toxic materials in the cytoplasm C. Packaging proteins for leaving the cell D. transporting proteins to the G.A.
A. folding and modifying newly synthesized proteins
How are peroxisomes different from lysosomes? A. peroxisomes are not packaged at the golgi B. peroxisomes are not membrane bound C. peroxisomes do not exist in eukaryotes D. lysosomes do not exist in eukaryotes
A. peroxisomes are not packaged at the golgi
Which of the following is a function of the smooth ER? A. it synthesizes proteins from mRNA B. it synthesizes lipids C. it provides a site for protein production D. it generates ATP
B. It synthesizes lipids
Why is the rough ER called rough? A. Because it is the site of toxic waste disposal B. Because it is studded with tRNA C. Because it is studded with ribosomes D. Because it operates at a low pH
C. Because it is studded with ribosomes
Which is NOT a similarity between nuclei and mitochondria? A. double membrane B. presence of DNA C. membrane embedded proteins D. use of binary fission
D. binary fission
Which is a function of the Golgi? A. synthesizing proteins from mrNA B. neutralizing toxins C. providing a site for protein production D. packaging proteins that will leave the cell
D. packaging proteins that will leave the cell
which proteins are multimeric? (a multimeric protein describes a protein that contains two or more subunits) a. F-actin b. g-actin c. keratin d. lamin
F actin, keratin, and lamin
neurons must have extensive: a. desmosomes b. microfilaments c. microtubules d. intermediate filaments
Microtubules: They are heavily implicated in transporting cargo around a cell - for example, vesicles containing neurotransmitters. Kinesins and dyneins are motor proteins which "walk" along microtubules like a road.
T/F: only mutations to the mitochondrial genome in mothers are heritable to offspring
T: mitochondria are inherited only from mothers, will not be passed down by father's DNA
Which of the following would be significantly increased by mutations affecting microtubule function? Select all that apply. a. birth defects b. mucus buildup in the throat c. male sterility d. DNA replication errors
a. birth defects b. mucus buildup c. male sterility due to chromosomal nondisjunction
Which processes do mitochondria play the biggest role?
aerobic cellular respiration (i.e. the krebs cycle, ETC, and ATP synthase)
Membrane bound organelles include: smooth ER ribosome mitochondria rough ER
all except ribosome
a cell is isolated that contains no organelles: which likely cell type is it? a. platelet b. RBC c. leukocyte d. neuron
b. RBC these cells expel their nuclei, genetic material and organelles during maturation processes. this is why RBCs are least helpful when studying genetic mutations
A loss-of-function mutation in a gene that codes for tubulin would most directly inhibit which of the following processes in meiosis? a. chromosome duplicaton b. chromosome separation c. genetic recombinaton d. chromosome condensation
b. chromosome separation
Which of the following are most likely NOT potential functions of cytoskeletal capping proteins? Select all that apply. a. cell movement b. promoting cytoskeletal polymer degradation c. muscle contraction d. promoting the Krebs cycle
b. promoting polymer degradation (capping proteins would inhibit degradation as it would prevent actin polymer breakdown) d. krebs cycle occurs in the mitochondria
True or false: Dyneins are the accessory proteins that carry neurotransmitter-containing vesicles to a neural synapse.
false: kinesins, move from the center towards the cell's edge/ move towards the synapse
True or false: Secretory proteins are transported from the endoplasmic reticulum to the trans-face of the Golgi apparatus.
false: secretory proteins are transported from the ER to the cis-face of the golgi; there they are packaged and then transported from medial to trans-face
what plays a role in cell movement?
microfilaments such as F-actin, G-actin
Centrioles are the major organizing center of :
microtubules
what maintains the structural integrity of the cell?
microtubules
place the following fibers in order of decreasing diameter: actin filaments, microtubules, and intermediate filaments
microtubules, intermediate filaments, actin filaments
Which of the following organelles is thought to have been created when specialized bacteria survived endocytosis into other bacteria? a. mitochondria b. golgi c. lysosome d. peroxisome
mitochondria: based on the endosymbiotic theory
capping a microfilament at the plus end would result in the microfilament: a. growing b. staying the same c. shrinking d. impossible to predict
shrink: capping prevents addition/removal of monomers; actin monomers fall off the minus end, and capping the plus end means no additional monomers would be added
microtubules are found in cilia and flagella of which cell types? a. sperm cells b. E.coli c. tracheal epithelial cells d. fallopian tube epithelial cells
sperm cells, tracheal epithelial cells, and fallopian tube epithelial cells
In which structure is are ribosomes assembled?
the nucleolus
True or false: damaged or malformed actin might lead to easily torn muscle fibers
true: muscle fibers contain actin microfilaments, where their movement causes muscle contraction in conjunction with myosin