sustainability and interdependence Flashcards
importance of biodiveristy
to maintain a wide variety of genetically diverse species
3 ways to measure biodiversity
species diversity
genetic diversity
ecosystem diversity
3 threats to biodiversity
human exploitation (overexploitation)
bottleneck effect
habitat corridors
explain over exploitation
when resource stock is placed under too much pressure leaving too few mature individuals that could produce the next gen.
explain the bottleneck effect
a sharp reduction in population due to a natural disaster resulting in a change in the frequency of alleles and a decrease in genetic variation
explain habitat corridors
a natural or man-made area of habitat that connects two habitat fragments allowing individuals to move between populations and helps to restore biodiversity
what is a naturalised species
a species which was originally invasive but has become established within the community
Annual weeds
Short life cycle
Rapid growth
High number of seeds produced
Dormant seeds remain viable for a long time
Perennial weeds
Long life cycle
Vegetative reproduction
Storage organs
Cultural control of weed growth (3)
Ploughing- top soil is turned over to bury perennial weeds
Removal of weeds- removed early in life of the crop, allowing the crop to get a head start
Crop rotation- different crops are grown each year to prevent the build up of pathogens
Chemical control pesticides (4)
Insecticides
Fungicides
Molluscicides
Nematocides
2 types of herbicides
Selective- stimulates growth until the plant exhausts its food resource and dies
Systematic- absorbed by the weeds vascular system where it’s transported around the plant and therefore prevents growth
Bioaccumulation
A build up of a chemical in an organism
Biomagnification
An increase in the concentration of a chemical moving between the trophic levels
Biological control
The control of a pest by the introduction of a natural predator
Integrated pest management
A strategy for controlling pests by combing the use of biological, cultural and chemical practices
Selective breeding is used to improve for,
Higher food yields
Higher nutritional value
Pest and disease resistance
Ability to thrive in particular environments
Why are plant field trials used for?
The see the difference in plant cultivars in the same conditions
To see the effect of environmental conditions have on a cultivar
When designing field trials you have to take in account for,
The selection of treatments-used to make a valid comparison
Number of replications- take account for the variability
Randomisation of treatments- to eliminate bias
Consequence of inbreeding
Decreased yield and decreased size
By what means can new alleles be introduced to a plant cultivar that is beginning to show inbreeding depression?
Crossbreeding
What does the Bt toxin do?
It gives plants a greater resistance to pests
factors effecting metabolic rate
Ph
salinity
temperature
why is it important to regulate temperature in the body?
so enzyme controlled reactions occur at their optimum
the bodies temperature monitoring centre?
hypothalamus
what is homeostasis
the bodies internal temperature in maintained within certain tolerable limits despite changes int he external environment
increase in body temperature results in…
vasodilation
sweating
erector muscles relax
reduction in metabolism
decrease in body temperature results in…
vasoconstriction
hair erector muscles contract
reduced sweating
shivering
increase in metabolism
The 5 freedoms
Freedom from:
Hunger and thirst
Discomfort
Pain, injury and disease
To behave normally
Fear and distress
Indicators of poor welfare
Stereotype- repetitive movement
Misdirected behaviour- a normal behaviour which is directed at others or themselves
Failure in sexual or parental behaviour- natural patterns of sexual behaviour either in terms of parenting or timing or action doesn’t happen. Abnormal parenting.
Levels of activity- apathy(very low) or hysteria (very high) levels of activity
Symbiosis definition
The relationship between two different species in direct contact with each other
What is the symbiosis when one organism benefits and the other doesn’t
Parasitism
What is the symbiosis where both organisms benefit
Mutualism
How can parasites be transmitted
Direct contact
Release of resistance stages (life cycle movements)
Use of a vector
Advantages of a social hierarchy
Increased change of survival due to:
Aggression is ritualised
Real fighting is kept to a minimum
Serious injury is avoided
Energy is conserved
Experienced leadership is guaranteed
Most powerful animals pass on their genes
Advantages of co-operative hunting
All members receive food
More food is gained
Hunting success is greater
Individual energy output is less
Advantages of staying is groups for safety
Weak, old and young are protected
Many eyes and ears to spot/hear danger
Predators are less likely to attack
If attacked multiple movements will confuse a predator
Examples of defensive movement in groups
Mobbing
Specialised formation
What is altruism
When an animal will behave in a way that disadvantages them whilst benefiting another animal
What is Kin selection
Acts of apparent altruism carried out to help close relations
3 types of honey bees
Queen
Workers
Drones
Worker bees roles
Cleaning out cells
Feeding and grooming larve
Storing pollen
Foraging for food
Protecting the hive
Pigments involved with photosynthesis
Chlorophyll a and b
Carotenoids
What is photolysis
The splitting of water
Explain light reactions
Light is absorbed by the pigment causing electrons to become excited.
Electrons move through electron transport chain, releasing energy, to generate ATP by ATP synthase.
The energy released is used to split water into oxygen and hydrogen which is then combined with NADP to form NADPH
What is the enzyme that controls carbon fixations
RuBisCO
Explain carbon fixations
CO2 combines with RuBP to form 3PG then it undergoes phosphorylation and combines with hydrogen ions to form G3P, some G3P is used to regenerate RuBP and the remainder is used to synthesis glucose
Uses of glucose
-respiration
-starch
-cellulose
biosynthesis pathways:
-DNA
-proteins
-fat
What does an absorption spectrum show
The absorption of light of each wavelength by each pigment
What does an action spectrum show
The rate of photosynthesis at each light wavelength
Adequate food security
Quality
Quantity
Access
2 components of species diversity
Number of different species
Relative abundance
