biodiversity extras to remember Flashcards
what is recessive epistasis?
homozygous recessive allele at first locus prevents expression of allele at second
What is dominant epistasis?
when dominant allele of one gene masks expression of allele at second
alpha glucose + alpha glucose=?
maltose
alpha glucose+ fructose=?
sucrose
beta galactose + alpha glucose=?
lactose
describe the structure of insulin (1)
2 polypeptide chains joined by disulphide bridges
describe th estructure of pepsin?(2)
stable in the acidic stomach bc acidic r groups
disulphide + hydrogen bonds
what is end product inhibition?
when the product stays bound to the enzyme
give an example of one metabolic poison and summarise its effects.
when eaten cyanide binds irreversibly to mitochondria, stopping aerobic respiration
give an example of one medicinal drug and summarise its effects.
protease inhibitor prevent replication of viruses in host cells by inhibiting the enzyme that makes viral coats
why do solvents affect the permeability of membranes?
they dissolve lipids, leaving holes in the membrane
what happens in G0? (2)
apoptosis
scenescence
what happens in G1? (4)
cells grow
transciption
organelles duplicate
enzymes for DNA replication
what happens in S phase? (2)
dna replication
rapid bc exposed base pairs susceptible to mutagenic agents
what happens in G2? (1)
Cells grow
proportion of polymorphic gene loci=
no. of polymorphic gene loci/ total number of gene loci
what are the 3 bacterial diseases
tuberculosis
bacterial meningitis
ring rot
what are the 3 viral diseases
HIV/AIDS
influenza
tobacco mosaic virus
what are the 3 fungal diseases
ringworm (cattle)
athletes foot
black sigatoka
what are the 2 protoctista diseases
malaria
blight
what are the examples of direct transmission in animals?
physical contact
faceal/oral
droplet infection
spores/vectors
what is the example of indirect transmission in animals?
vector (e.g. malaria)
describe the transmission of malaria?
mosquito=vector
plasmodium in saliva
bites human
plasmodium passes to blood
what are 3 extra factors that influence transmission of disease
living conditions, climate, social factors
list physical plant defences that limit the spread of a pathogen?
callose deposition- blocks sieve tubes cellulose cell wall lignin thickening waxy cuticles bark stomatal closure
list the chemical plant defences against pathogens
terponoids phenols alkaloids defensins hydrolytic enzymes
necrosis- deliberate cell suicide
list the primary non-specific defences against pathogens?
skin, blood clotting, wound repair inflammation expulsive reflexes mucous membranes
describe the structure of a phagocyte
cytoskeleton to allow flexibility to engulf pathogens
describe the mode of action of a phagocyte
pathogen engulfed by endocytosis
trapped within phagosome
lysosomes containing hydrolytic enzymes fuse with phagosome
digest pathogen
what is the role of cytokines, opsonins, phagosomes and lysosomes.
cytokines- cell signalling molecules
opsonins- bind to pathogen’s antigen allowing phagocytes to bind
describe the specific immune response
macrophage engulfs pathogen + presents anitgen on surface
t-helper detects foreign antigen + releases interlukins (a type of cytokine)
which stimulates b and t cell production- clonal selection= choosing which cells are produces
clonal expansion= mitosis of specific b or t cells
b cells differentiate into plasma or memory
memory provides long term immunity, plasma releases antibodies
either opsonins, aggultanins, or antitoxins
t-killer cells kill infected host cells
t regulator cells end immune response
what are agglutanins?
antibodies sticking pathogens together
what are anti-toxins?
antibodies rendering toxins harmless
what is an autoimmune disease?
immune system attacks body e.g. arthritis, lupus
whats the difference between passive and active immunity?
immune system activated
antibodies passed on through breastfeeding/injection
whats the difference between artificial and natural immuunity?
medicinal intervention
normal life processes
whats conservation in situ?
In natural environment
what are the 3 factors affecting biodiversity?
human pop growth - pollution
agriculture- monoculture no genetic diversity
climate change- animals not adapted
what are the economical aesthetic and ecological reasons to maintain biodiversity?
Ecological- protectng keystone species maintaining genetic resource
• economic including reducing soil depleton (contnuous monoculture)
• aesthetc, including protectng landscapes.
what are 2 example of in situ conservation?
marine conservaton zones and wildlife reserves
what are 3 examples of ex situ conservation
including seed banks, botanic gardens and zoos.
what does CITES do?
regulates species trade
check trade doesnt endanger
less endangered may be traded
what does the countryside stewardship scheme do?
farmers given money to maintain historical sites by building walls and planting trees
what does the rio convention do?
shares biological knowledge about species and conserves biodiversity
what features are used to classify plantae?
autotrophic cellulose cell wall
what features are used to classify prokaryotae?
no nucleus smaller ribosomes
What features are used to classify protoctista?
euakryotic, auto/heterotrophic