Lab Notes + Appendix A

What do we do in science?

- develop ideas, design experiments, conduct observations to test ideas, uses statistical methods to interpret our results, and communicate our findings to larger community

what is the study of science?

- study of natural phenomena

what is the scientific method?

- tool we used to achieve high standards of research
- overcome biases and conduct logically reliable research

what are the steps of the scientific method?

1. observing outside world through our senses
2. asking a question about natural phenomena
3. hypothesizing an explanation for the phenomenon
4. testing the hypothesis through a correlational/experimental study
5. collecting and analyzing data from the experiment
6. creating a conclusion from the experimental data

Observations

- receiving knowledge of the outside world
- observations of phenomenon
- preliminary observations allows use to formulate questions about our surroundings, which we can investigate

Questions

- how's and why's of nature
- relevant questions that have capacity to be testes
- form of question can influence the type of study

Hypothesis

- tentative answer to your question
- clearly stated, proposed explanation for observations
- states factors that influence observed phenomena
- we can only disprove hypotheses

Null Hypothesis

- when hypothesis is rejected, provides support for our hypothesis
- proposes no relationship between factor being studied and observed phenomenon

What is the difference between hypothesis and null hypothesis?

- null states that the factor has no effect on the observed results
- hypothesis states it has an effect on the results

What makes a good hypothesis?

- testable predictions
- ability to generate specific predictions of scenarios that will reject or fail to reject your null hypothesis

What is experimental manipulation?

- used artificial manipulation to investigate the relationship between one factor and another
- actively altering the study system and measures the effects of manipulation

what are correlational studies?

- use natural variation to investigate the relationship between one factor and another
- observing nature

what is the independent variable?

- factor that is being manipulated in the study
- was is altered in the system is controlled by the researcher

what is the dependant variable?

- factor that is expected to be affected by the manipulation

What does an experimental manipulation test?

it tests whether the independent variable has an effect on the dependant variable

What is a control group? or a control?

- reference to which the results of an experiment manipulation can be compared
- act as a reference to measure the effect of the experimental manipulation on the dependant variable
- ensure that conclusions drawn from an experimental manipulation are biologically valid

Advantages of Correlational Study

- less handling of organisms
- systems under study are more likely to be observed in their natural state
- represent biologically relevant variation
- experimental manipulation is not practical or ethical

Advantages of Experimental Manipulation

- more likely to control for confounding variable
- know direction of causation

What are confounding variables?

- factors that the researcher failed to control or eliminate which can damage the validity of an experiment

What are controlled variables?

- variables that are held constant
- EM allows for more control for confounding variables

Analyzing and Interpreting Data

- what does your data tell you?
- tests of significance

What are the two tests of significance?

x^2-square test and t-test

Theory

- explaining and predicting natural phenomena
- if proven, hypothesis may be accepted as part of general theory

What makes a good theory?

- it accurately describes a large class of observations
- makes definite predicts about the results of future observations

What do reduviid bugs do?

- they cover their thorax with a layer of dust, sand, and soil particles to form dust coat
- attack dead ants to thorax using elastic threads that are produced by glands on their back to from backpack

What are adaptations?

- traits that contribute to fitness by increasing organisms chance of surviving and reproducing
- physical feature or a behaviour

What are arthropods?

- insects, animals with jointed legs

What are the three main sections in arthropods?

- head, thorax, abdomen

What is Natural Selection? according to Darwin

- process of adaptation

How are new traits and combinations of traits created?

- through mutations and recombination

how is fitness measured?

- as the number of offspring an individual produces relative to another in the population

what is evolution?

- the change over generations in the proportion of individuals with a certain trait

What are the 3 criteria for a trait to evolve?

1) is heritable
2) variation btw individuals
3) variation in trait leads to individuals leaving more offspring in next generation than others

How else can populations change and evolve?

genetic drift and gene flow

What id the difference btw viability and competition?

- viability is the success in survival and acquisition
- competition is for mating; reproduction

What is viability selection? Examples?

- natural selection arising from variation in viability
- camouflage in grasshoppers; avoid predation
- feeding; ants have strong jaw (mandibles), butterflies have long tongue (proboscis)

What is sexual selection?

- natural selection arising from variable mating success
- results in secondary sexual characteristics

What is sexual dimorphism?

- difference in shape or size of male and female

What are two principles of sexual selection?

- intersexual competition
- mate choice

What is intersexual competition?

- males fight with other males for access to females
- male who wins usually has more offspring
- examples: horns, tusks, "weapons"
- females usually have smaller version

What is mate choice?

- females and males that choose their mates
- attractive individuals produce more mates
- examples: structure, colouration, courtship

What is a complete metamorphism?

- undergoing a series of profound changes in body form, behaviour, and lifestyle
- eggs hatch into larvae (caterpillars), feed on vegetation
- becomes pupa; in cocoon caterpillar develops into adult
- butterfly feeds on nectar and flowers can reproduce

What is warning colouration?

- colours warn predators and makes them seem dangerous

How are water striders able to stay still on water?

- fine hairs that are water repellent
- females engage males in pre-mating struggles
- capture insects entrapped by water's surface tension
- light weight
- thin legs
- good eyesight

What are the uses of the water striders legs?

- front allow them to grab predators
- middle act as paddles
- back provide power, steer and brake

How do water striders grab prey?

- grab prey quickly
- use moth parts to pierce and suck juice

Why do male leaf insects prefer longer females?

- because longer females produce more and larger eggs

Why do male Madagascar hissing cockroaches have bumps on their dorsal prothorax?

- plate that protects their head
- fend off rivals

Why do waterfleas grow long heads and tails?

- they grow them as a response to the presence of predators
- spines interfere w the predator's ability to consume the flea

What is phenotypic plasticity?

- single genotype can produce different phenotypes in response to its environment

what is a phenotype?

- observable appearance of a specific genotype

what is an organism's phenotype composed of?

morphology, behaviour, and physiology

What can variation in a phenotype be a result of?

- genetic variation
- the environment
- interactions of both components

What does this graph tell us?

- genotype affects height

What does this graph tell us?

- genotype does not affect height
- environment affects height

What does this graph tell us?

- both genotype and environment affect phenotypic variation

What is a genotype?

- organism's allele
- complete genetic constitution of an organism

What are quantitative or polygenic traits?

- continuous traits such as hair, skin colour
- result of genes and environment
- large or small effect on phenotypic expression

What is acclimation?

- altering the phenotype
- individuals acclimate to their environment

What is phenotypic plasticity?

- individual can alter the expression of a phenotypic trait in response to the environment
- ability of one genotype to produce different phenotypes in different environments

What are the two types of phenotypic plasticity?

- discrete and continuum

Why are not all traits phenotypical plastic?

- insufficient genetic variation
- inherent costs and limitations to the benefits of PP

What is a limitation w producing phenotypes?

- accuracy w which an organism can process environmental cues to acclimate
- time difference btw environmental change and alteration of phenotype

What is a maladapted phenotype?

- organism senses environment incorrectly or rapidly

what sort of individual is able to acclimate to changing conditions in terms of number of genotypes?

- an individual which can produce more genotypes is more likely to acclimate to changing conditions then individual who can only produce one

Stereo Microscope

- three-dimensional
- less magnification power

What are the parts of a Stereo Microscope?

What is a ocular micrometer?

- precise measurement of objects under the microscope

What is a phytochrome?

- a photoreceptor that detects shading by other plants
- detects like quality
- regulates gene expression
- genes alter morphological, physiological, and biochemical characteristics in plants

what are the parts of a compound microscope?

what are the major differences btw a compound microscope and stereo microscope?

- compound microscope does not have adjustment knob
- two focus adjustment knobs on compound microscope
- move stage up and down on a compound microscope
- light is shone from below the stage on a compound

What is magnification?

- factor by which the image of a specimen is enlarged
- magnification of objective lens times the magnification of the ocular lens

How is an ocular micrometer is calibrated?

- against the stage micrometer

What are the parts of a leaf cross-section?

What is an upper epidermis?

- layer of transparent cells; light is absorbed through this layer

what is a cuticle?

- waxy layer which retards water loos from leaf surface

what is palisade mesophyll?

- layer beneath upper epidermis, cells that do photosynthesis

What are spongey mesophyll?

- cells that carry out photosynthesis

What are chloroplasts?

- in mesophyll cells
- moves up into direct light, moves down to shaded part

What are vascular bundles or veins?

- xylem: carries water to mesophyll cells
- phloem: carbohydrates by photosynthesis into mesophyll, transports to rest of plant

What are lower epidermis & stomata?

- where gas exchange and water evaporation occur

Why do devil's garden only have one species of tree?

because ants are responsible for keeping out other species

What are plant-animal interactions important?

- animals that feed on plants retain energy from plants
- organisms help plants to reproduce and survive
- lead to array od adaptations, which spur diversity

What are the different types of Interactions?

- mutualism
- competition
- consumer-resource interaction

What is a positive effect?

- species benefit from interaction

What is negative effect?

- species do not benefit from reaction

What is no effect?

- species have no cost or benefit of interaction

What is effect does completion have?

- negative effect
- same resources between species

What is the effect of mutualism?

- both species benefit
- example: animal pollination

What is the effect of consumer-resource interactions?

- positive effect on one species
- negative on another
- example: predator and prey

What are plant-herbivore interactions? negative or positive effect?

- herbivores that feed on plants
- reductions in seed set decrease plant fitness
- herbivores that consume and kill seeds have - effect
- transmit bacteria and viruses through mouth

What is plant resistance?

- traits that increase a plants' resistance to herbivory
- resist attacks through tolerance and defence

what is tolerance?

- plant's ability to reduce effects of herbivory on fitness
- physiological responses

what is defence?

- trait that reduces damage to a plant by herbivores

What are the three different defences?

- timing of flowering or leaf production
- structural defences
- chemical defences

What is phenology the study of?

- life cycles of plant and animals in relation to seasonal changes
- producing flowers when herbivores are least abundant

What are some structural defences?

- roses have thorns
- poppies have trichomes hats that trap herbivores, preventing them from laying eggs or feeding

what are some chemical defences?

- protease inhibitors
- PSMs

What are constitutive defences?

- does not significantly fluctuate over time

What are induce defences?

- chemical is produced in response to damage