Chapter 6 Bell-ringers and Other Questions Flashcards
Explain why there are both upper and lower limits to cell size.
Carrying out cellular metabolism sets limits on the size of cells. The surface area to volume ratio of a cell is critical. Small cells have a greater surface area relative to volume. They have to be small enough to diffuse things in and out of the cell in a timely matter, so the cell doesn’t die. Eukaryotic cells have to hold more organelles, so they tend to be larger than prokaryotes.
Explain why compartmentalization is important in eukaryotic cells.
Compartmentalization allows each compartment to perform specific functions without interference from other cell functions. For example, lysosomes can break down cell debris in a compartment without accidentally digesting the cell itself.
What are some characteristics that all cells share?
All cells have a plasma membrane, cytosol (semi-fluid substance called cytoplasm in some cells), chromosomes, and ribosomes
Describe the difference between prokaryotic and eukaryotic cells.
Eu:
-Membrane Bound Organelles, nucleus, bigger in size
Pro:
-Free floating nucleus, usually smaller, no MBO
Both: DNA, Ribosomes, Membranes, cell walls
Describe the structure and function of the nucleus and briefly explain how the nucleus controls protein synthesis in the cytoplasm.
The nucleus is a membrane bound structure that contains the cell’s hereditary information and controls the cell’s growth and reproduction. The nucleus is enclosed in a nuclear envelope that separates it from the cytoplasm and prevents mutations.
The nucleus regulates the synthesis of proteins in the cytoplasm through the use of mRNA. mRNA is a transcribed DNA segment that serves as a template for protein production. Once in the cytoplasm, ribosomes and transfer RNA work together to translate mRNA to produce proteins.
Describe the endomembrane system, include parts and functions.
The endomembrane system consists of many parts, such as the nucleus, the nuclear envelope, the endoplasmic reticulum, mitochondria, the Golgi apparatus, lysosomes, and the plasma membrane.
The nuclear envelope is a double membrane enclosing the nucleus, to separate the contents of the cytoplasm from DNA in the nucleus.
There is a rough and smooth endoplasmic reticulum, with the rough ER having ribosomes. The rough ER makes little parts of a protein, and the smooth ER detoxifies.
Mitochondria are found in the cytoplasm, and help make energy for the cell.
The Golgi apparatus synthesizes, modifies, sorts, and secretes proteins.
Lysosomes help break down old parts of the cell and help to digest
The plasma membrane holds the cell with all its organelles together.
Explain the characteristics of mitochondria and chloroplasts.
Both mitochondria and chloroplast share many of the same characteristics, such as: having their own DNA, making ATP, reproducing independently in the cell, using their own ribosomes, and having inner and outer membranes. Although they have similar characteristic, mitochondria can be found in both animal and plant cells, where chloroplasts can only be found in plant cells.
