Life on Earth and Macromolecules Flashcards
What are the common characteristics of life?
Growth, metabolism, response to stimuli, movement, and reproduction
What is the smallest unit of life?
Cell
True/False. New cells arise only from pre-existing cells.
True
True/False. Multicellular organisms cannot arise from a single cell.
False. It can.
What is central dogma?
Central Dogma is the major principal which allows cells to take control of itself.
What is the function of DNA?
DNA stores genetic information
Why is genetic information written on DNA expressed?
To produce a product which is used to control cellular activity.
How are copies of cells made?
DNA replication
What are the steps of central dogma?
DNA synthesis -> DNA -> RNA synthesis -> RNA -> protein synthesis -> protein
What is the difference between prokaryotes and eukaryotes?
Prokaryotes do not have defined nucleus while eukaryotes have a true nucleus.
Aside from nuclei, what do prokaryotes lack?
membrane-bound organelles
Are prokaryotes smaller or larger than eukaryotes?
Smaller
What are macromolecules?
Macromolecules are building blocks of life.
What are the four different kinds of blocks?
Sugars, fatty acids, amino acids and nucleotides
When each of the four building blocks are organized, what major cellular structures are built?
Sugars – polysaccharides
Fatty acids – fats, lipids, membranes
Amino acids – proteins
Nucleotides – nucleic acids
How are polymers formed?
When monomers of sugars, amino acids and nucleotides are linked together.
What do all cells use as catalysts? What else?
All cells use proteins as catalysts. Nucleotides especially RNA can also be used as catalysts.
How are fatty acids different from sugars, amino acids and nucleotides?
Fatty acids usually do not polymerize the same way sugars, amino acids, and nucleotides would do. They group together to form various membranes found in cells.
What one feature of phospholipids?
They have hydrophilic head group and hydrophobic tails
What strain of the bacterial pathogen streptococcus pneumonieae causes pneumonia and what strain does not?
Smooth (S) strain causes pneumonia and rough (R) strain does not.
How is R strain converted to an S strain?
When different macromolecules from S strain extracts and purifies, transfers it into the R strain, and the R strain receives DNA of S strain.
What happens to the R strains that receive other molecules (not DNA) of S strain?
They do not get converted to an S strain.
Describe the central dogma in eukaryotes in steps.
DNA -> synthesis of mRNA in the nucleus -> RNA -> mRNA needs to cross the nuclear membranes to get into cytoplasm so it moves via nuclear pore -> synthesis of protein -> protein
What is the function of ribosomes in the cytoplasm during the central dogma in eukaryotes?
Ribosomes translates mRNA into proteins in the cytoplasm.
