3 - Cell Structures and Their Functions Flashcards
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What are cells?
cells are highly organized units containing organelles, which perform specific functions.
What is in the nucleus?
The nucleus contains genetic material.
What is the cell membrane composed of?
The cell membrane is composed of a double layer of phospholipid molecules in which proteins float. The proteins function as membrane channels, carrier molecules, receptor molecules, enzymes and structural components of the membrane.
What is diffusion?
Diffusion is the movement of a solute from an area of higher concentration to an area of lower concentration within a solvent.
What is a concentration gradient?
A concentration gradient is the concentration of a solute at one point in a solvent minus the concentration of that solute at another point in the solvent divided by the distance between the points.
What is able to diffuse through the membrane?
Lipid-soluble molecules and gases.
What is the structure of the nucleus?
The nuclear envelope consists of two separate membrane that form nuclear pores at many points on the surface of the nucleus.
What are ribosomes?
Ribosomes are the sites of protein synthesis. A ribosome is composed of one large and one small subunit.
What is rough ER?
Rough ER is Endoplasmatic Reticulum with ribosomes attached. it is a major site of protein synthesis.
What is smooth ER?
Smooth Endoplasmatic Reticulum does not have ribosomes attached and is a major site of lipid synthesis.
What is the Golgi Apparatus?
The Golgi Apparatus is a series of closely packed membrane sacs that collect, modify, package, and distribute proteins and lipids produced by the ER.
What are lysosomes?
Lysosomes are membrane-bound sacs containing enzymes. Within the cell, lysosomes break down phagocytized material.
What are peroxisomes?
Peroxisomes are membrane-bound sacs containing enzymes. Peroxisomes break down fatty acids, amino acids, and hydrogen peroxide.
What is transcription?
During transcription, the sequence of nucleotides in DNA determines the sequence of nucleotides in mRNA.
What is translation?
During translation, the sequence of codons in the mRNA is used at ribosomes to produce proteins. Anticodons of tRNA bind to the codons of mRNA, and the amino acids carried by tRNA are joined to form a protein.
