Unit 2 Flashcards
Define “INTERspecific variation”
Variation that exists between DIFFERENT species
Define “INTRAspecific” variation:
Variation that occurs WITHIN a species e.g. The number of “eyes” on peacock’s feathers
Why do scientists look at a sample of a population rather than the whole population?
- time-consuming
- impractical/impossible to catch all individuals
so, samples are used as MODELS for the whole population
Why does a population sample have to be chosen RANDOMLY?
- Prevent BIAS
* Ensure any variation observed isn’t due to CHANCE
How is each amino acid coded?
by a SEQUENCE OF 3 BASES, called a TRIPLET
!!!!IN A GENE!!!!
Genes in EUKARYOTIC DNA don’t code for Amino Acids, what are they called and when are they removed?
- Introns
- ((also contains regions of MULTIPLE REPEATS outside of genes))
• Protein Synthesis
How can a GENE MUTATION ➡️ NON-FUNCTIONING PROTEINS?
- Change in hydrogen/ionic bonds
- Alters primary and therefore, tertiary structure/active site
- Substrate cannot bind - no longer complementary
- No E-S complexes form
Why is comparing the BASE SEQUENCE OF A GENE better than comparing the AMINO ACID SEQUENCE?
- Introns don’t code for DNA
- DIFFERENT BASE TRIPLES CODE FOR THE SAME AMINO ACID
- DNA code is degenerate
• STOP/START Sequences
Explain the relationship between the SA:VOL ratio and their OXYGEN DISASSOCIATION CURVES of their HAEMOGLOBINS
- Smaller mammals have GREATER SA-Vol ratio
- therefore, more HEAT ? lost per unit BODY MASS
- also, greater rate of RESPIRATION
- OXYGEN required for respiration
- HAEMOGLOBIN releases OXYGEN more READILY - ⬇️ AFFINITY
How does a DOUBLE BLIND TEST improve reliability?
• PREVENTS BIAS, which may have otherwise occurred due to the VESTED INTEREST OF SCIENTISTS ?
- PREVENTS “PLACEBO” effect
- PREVENTS DEMAND CHARACTERISTICS from VOLUNTEERS
How could you use the graph to predict…
- use LINE of BEST FIT ➖
* EXTRAPOLATE then READ FROM GRAPH
Define an “Organ”
made up of
DIFFERENT
tissueS
Why does a LACK of protein lead to the build up of Tissue Fluid?
- WP not AS low
- LESS WATER REMOVED INTO CAPILLARY
- via Osmosis, INTO capillary
Define “Genetic Bottleneck”:
- Drop in population
- ⬇️ GENETIC VARIATION
- SMALLER gene pool
Why is _____ FERTILITY low?
- Mutation affecting SPERM CELL (in small population)
- ERRORS IN MEIOSIS
- Inbreeding
- HIGH CHANCE of inheriting allele
Why does the rate of water uptake ⬇️ when you cut off a plant’s leaves?
- ⬇️ SURFACE AREA
- FEWER STOMATA ?
- Less TRANSPIRATION
- LESS COHESION
Osmotic Lysis:
- CELL WALL production is INHIBITED
- LOWER WP in BACTERIUM
- Water enters and causes LYSIS
Ethical argument for MAINTAINING BIODIVERSITY?
• Prevent EXTINCTION of animals and save them for FUTURE GENERATIONS
An economic argument for maintaining biodiversity?
- TOURISM ?
* COMMERCIAL PRODUCTS
Deforestation’s effects?
- Fewer PLANT species ?
- Fewer HABITATS ?
- Fewer NICHES
- Fewer FOOD sources ?
- LESS PROTECTION FROM PREDATORS ?
How to identify “INTERPHASE”
- NO VISIBLE CHROMOSOMES
* VISIBLE NUCLEUS
If the Standard Deviation bars DO NOT overlap, what does that tell you?
ALSO!!! LOW Sds means RESULTS MORE RELIABLE ❗️❗️❗️
(differences) ARE significant and not due to chance ?
Why repeat the measurement several times?
- Identify Anomalies
* makes the AVERAGE MORE RELIABLE
Why Self-Report was less reliable?
RESULTS rely on their OWN JUDGEMENT
Some ppts may LIE/EXAGGERATE
