wrong questions Flashcards
(26 cards)
fossil evidence for natural selection
fossils show change over time, development of species over time, evidence of extinction, how organisms from the past are related to species alive today
genetic evidence for natural selection
mendel’s breeding experiments
genetic variation in a species due to mutation
antibiotic resistance in bacteria
why the change in the number of chromosomes in meiosis is important
meiosis forms gametes
two gametes fuse/fertilise
so keeps chromosome number constant from generation to generation
rp10 explain why the pH changes more quickly when the temp is higher
enzymes work more quickly
lipids broken down more quickly
so fatty acids produced more quickly
what is tissue culture
a group of cells grown into a new organism
why does decrease in body temp is an advantage during hibernation
lower temperature gradient between animal and air
loses less energy as heat from body
so body energy store lasts longer
how does dilation of blood vessels in the skin help to decrease body temperature
increase blood flowing near surface of skin
increase heat lost
which cools blood which cools the body
why do athletes who sweat a lot are advised to take salt tablets each day
to replace mineralions lost in sweat
why do plants not decay in peat bogs
lack of oxygen for aerobic respiration
so no energy released for microorganisms
low ph denatures enzymes so less metabolism/respiration/no energy released in microoragnimsn
why control needed
to COMPARE with other thing
uses of auxin
weed killers
rooting powders
uses of ethene
stimulate ripening of fruit
uses of gibberellins
growing larger fruit
inducing flowering (more/bigger flowers)
inducing germination
what scientific term describes the structure of dna molecule—made of two strands twisted around each other
double helix
steps for tissue culture why: several groups of cells are scraped off the leaf
so many/several plants can be produced
steps for tissue culture why:nutrients added to the agar jelly
for making protein/amino acids
making chlorophyll
providing energy/for respiration
steps for tissue culture why: hormones added to the agar jelly
so roots and shoots develop
or so differentiation occurs
steps for tissue culture why: sterile conditions
to prevent growth/entry of microorganisms
steps for tissue culture why: temp at 20c
for optimum growth
why does a person with type 2 diabetes has higher blood insulin conc than a non diabetic person
cells absorb less glucose
glucose conc in blood remains high
stimulates pancreas to release more insulin
why more land is being used for farming and why increased farming has lead to biodiversity
incr population incr food
crops for food
crops for biofuels
peat use as compost/fuel—CO2
increase use of pesticides
loss of habitat—mass migration
fertiliser run off
use of pesticide damages food chains
more CO2–global warming
acid rain
how does brain recieve info about light entering eye
retina sensitive to light
impulse passes along sensory neurone in the optic nerve
how does making dog food from insects improves human food security in future
less land required
so more space for crops for human food
so less methane from animals released so less global warming
so less harmful effects of global warming on food production, e.g. floods.
why fossil record is incomplete
fossils buried deeper so hard to find
fossils smaller so harder to find
more likely to be destroyed by geological activity
oldest organisms were softbodied so tissue decayed
dating older fossils is hard
older eras less researched by scientist because less to find
unclear when one species evolves into another species
