Section 1: What is Life? Flashcards
ecology
the study of interactions among organisms and between organisms and their environment
photosynthesis
h2o+co2+light forms oxygen+carbohydrates (store energy)
respiration
o2+carbohydrates form H2o+co2+energy
what is virus latin for?
poison
2 main characteristics of viruses
contain genes
subvert protein synthesis of host cells
gene is the information for…
one protein
analogy for genetics
DNA=paper and ink
gene=sentence (info) written with DNA
ACTG (molecules)=letters
codons=3-letter words
codons respond to
amino acids (make up proteins)
controlling protein synthesis leads to control of
chemical reactions
poison dart frogs
bright colors warn predators
feed during day
get toxins from eating ants
predator: fire bellied snake has neutralizing agent in saliva
what did the viking landars do?
conduct 4 tests for life on mars
found life is about chemistry/chemical reactions
3 basic types of bacteria
round
rod
spiral
anaerobic sulfate reducing bacteria
produces sulfide
purple sulfur bacteria
uses infrared light to produce sulfur
cyanobacteria (blue green algae)
nitrogen fixer, limited by phosphorus
connection between anaerobic sulfate-reducing bacteria, purple sulfur bacteria, and cyanobacteria
dying cyanobacteria releases sulfur, increasing anaerobic sulfate-reducing bacteria and production of sulfide
increased sulfide increases purple sulfur bacteria, decreasing infrared light
evolution
change in the genetic makeup of a population through time
bacteriophage life cycle
bacteriophage finds cell
attaches to cell, injecting with own DNA
produces proteins using host machinery
cell produces bacteriophage proteins
bacteriophage destroys cell
are viruses, DNA, and genes immortal?
viruses and DNA degrade
genes are potentially immortal
mutation
change in gene that is passed from one generation to the next
random error during replication, rare and rarely beneficial
do viruses and bacteria contain genes?
yes
do viruses and bacteria evolve?
yes
do viruses and bacteria reproduce?
yes
do viruses and bacteria require a host?
viruses do
some bacteria do
do viruses and bacteria transform energy?
viruses don’t
bacteria do
all living organisms exist because…
they survive and reproduce
what is life?
the information to harness energy needed to perpetuate that information
smallpox virus
first disease with successful vaccine, to be eradicated
types of vaccines
related viruses: smallpox
inactivated viruses: influenza
attenuated (still infectious but slow) viruses: measles
mRNA: covid
2 origins of viruses
- regression (degeneration) ex. bacteria loses genes
- cellular origin (escape) ex. DNA/RNA going bad
