Thylakoids, DNA and ribosomes are all components found in ?
Which structure function pair is mismatched?
ribosome ----lipid synthesis
in an animal cell, DNA may be found?
only in the nucleus and mitochondria
Cells of ovaries and testes synthesize lipid containing hormones estrogen and testosterone respectively, Which of the following structures is primarily involved in this process and therefore abundant in these cells?
Smooth endoplasmic reticulumn
What are mitochondria and chloroplasts not classified as part of the endomembrane system?
they are not derived from the endoplasmic reticulumn or golgi apparatus
Which cell type has abundant lysosomes?
phagocytic white blood cells
What do the cell walls of plants and the extracellular matrix of animal cells have in common?
they have functional connections with the cytoskeleton inside the cell
Which of the following statements about the cytoskeleton is TRUE?
Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other
Plasmodesmata in plant cells are most similar in function to_______in animal cells?
Which of the following types of molecules are the MAJOR structural components of the cell membrane?
phosphoilipids and proteins
Which of the following us/are the way that the membrane of certain plants are able to remain fluid when it is extremely cold in winter
by increasing the high proportion of unsaturated hydrocarbon tails in phospholipids
The movement of O2 and CO2 into and out of a cell through the cell membrane phospholipid bilayer is an example________, where as the movement of water into and out of a cell thorugh aquaporins embedded in the cell membrane is an example of________.
diffusion, facilitated diffusion
The disease hypercholesterolemia (high blood cholesterol) is characterized by which of the following?
defective cholesterol receptors on the cell membrane
both sodium and potassium pump and proton pump
The difference between pinocytosis and receptor-mediated endocytosis is that
pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor mediated endocytosis involves specific receptor therefore offers more selectively
in order for a protein to be an integral membrane protein it would have to be
amphipathic, with both hydrophilic and hydrophobic regions
The extracellular matrix participants in the regulaation of animal cell behavior by communicating information from the outside to the inside of the cell via which of the following?
Mammalian blood contains the equivalent of .15M NaCl. What will happen if red blood cells are transferred to disitilled water
The red blood cells will take up water by osmosis, swell, and eventually burst or lyse
In a naturally properly folded cellular protein where would you expect to find a hydrophobic amino acid such as leucine?
B and C
Which of following membrane activities requires energy from ATP hydrolysis
Sodium /Potassium pump across the cell membrane against their concentration gradients
Which parts of animal cell membrane function to mediate cell to cell recognition?
Carbohydrates attached to glycoproteins and glycolipids
In cell signaling the protein membrane receptors are activated, what usually happens?
the receptor changes conformation after binding with signal molecules
In signal transduction how is a signal transmitted through a series of proteins?
the signal is transmitted by phosphorylation of each protein which leads to each proteins conformational change
The function of phosphatases in signal transduction is best described as to?
inactivate protein kinases and turn off the signal transduction
What is the greatest advantage of having multiple steps in a signal transduction pathway?
Multiple steps provide for greater possible amplification of a signal