Card 0 of 5
The shape of an animal cell is determined by which of the following?
The cytoskeletion determines cell shape. The cytoskeleton consists of three different types of filamentous proteins: microfilaments, intermediate filaments, and microtubules. Elements of the cytoskeleton can interact with the cell membrane and cell junctions to alter the cell's overall structure.
There are no cell walls in animal cells, although the cell wall does play a large part in determining cell shape in organisms that possess them (plants, bacteria, fungi).
Compare your answer with the correct one above
Which organelle works to synthesize an unstable form of energy?
The unstable form of energy that is syntheisized refers to ATP. ATP is an unstable; its three phosphate groups are all negatively charged and repel one another. Remember that BOTH the mitochondria and chloroplast participate in ATP synthesis via chemiosmosis; however, only the chloroplast participates in glucose synthesis via photosynthesis. Note that glucose is a stable form of energy and is not readily usable until it is broken down in the process known as glycolysis.
Compare your answer with the correct one above
The nucleolus __________.
The nucleolus is a subdivision of the nucleus; thus, it is only found in eukaryotes. It is the site of ribosome assembly. The nucleolus is made of RNA and proteins.
Compare your answer with the correct one above
Histones __________.
Histones are proteins found in the nucleus of eukaryotic cells. DNA wraps itself around histones to further condense. Also, depending on how tightly the DNA is wrapped around the histones, it may or may not be availible for activity (e.g. replication or transcription). Cells modify the interaction between DNA and histones around certain genes under certain conditions to make those genes available or unavailable as needed.
Compare your answer with the correct one above
In which of the following organisms are vacuoles not usually found?
Vacuoles are membrane-bound structures that are found in bacterial, plant, fungal, and occasionally, animal cells. Vacuoles function in storage of water and waste and in maintenance of turgor pressure in plants.
Compare your answer with the correct one above