module 6 (2) Flashcards
(30 cards)
why is reduced heart rate seen in fit people
increased stroke volume
increase ventricule volume chamber
increased strength of heart muscle
why, at the end of the day is a small proportion of organism’s mass is ATP
ATP is constantly recycled
ATP is not stored long-term
ATP is broken down to ADP
why are some DNA regions non-coding
not present in mature mRNA
not translated
regulatory genes
why is it sometimes needed to conserve a plant ex situ
ecosystem lost due to human activity
population is low
maintains gene pool
protection from grazers and competing species
protection from disease
why do non-coding regions show more variation
not selected against
why is there a higher % for protein sequences than cDNA sequences
genetic code is degenerate
silent mutations
DNA changes more than is more different to protein
how can bacteria be modified to produce a protein
use restriction enzyme to cut out gene + gene probe to obtain mRNA
use reverse transcriptase to make cDNA with sticky ends
cut open plasmid using same restriction enzyme and anneal using DNA ligase to make recombinant vector
mix with bacteria
how does DNA allow replication
double stranded
both strands act as template
hydrogen bonds easily broken
complementary base pairing
purine only bind to pyrimidine
define mutagen
agent which increases likelihood of mutation
how are ionisating radiations mutagens
break DNA strands
how are deaminating agents mutagens
alter bases
how are alkylating agents mutagens
methyl/ethyl groups attached to bases result in incorrect base pairing
how are base analogs mutagens
incorporated into DNA in place of usual base sequence
how are viruses mutagens
insert itself into genome
what is the difference between a gene mutation and a chromosomal mutation
gene = occur in single genes
chromosomal = affect the whole chromosome
what are the different types of chromosal mutations
deletion
duplication
translocation
inversion
how does bacteria respond to the environment
gene regulation
express genes only when the products are needed to prevent waste of resources
why do we use fruit flies
small
easy to keep
have short-life cycle
what are homeobox genes
group of genes which contain a homeobox
section of 180 bp coding for a part of protein that is highly conserved
what is the part of the protein the homeobox codes for called
homeodomain
what does a homeodomain do
binds to DNA and switches genes on or off
what are hox genes
group of homeobox genes in animals
responsible for correct positioning of body parts
what are diploblastic organisms
have two primary tissue layers
what are triploblastic organisms
have three primary tissue layers
