A level Biology Flashcards
Calvin cycle
CO2 (fixed because it has been removed from environment and become part of cell)+RuBP=GP (rubisco)
2 ATP+2 H from NADPH=reduce GP to TP
5/6 TP+ATP regenerates RuBP
1/6 TP=starch/cellulose/amino acids
Biodiversity
Variety of ecosystems and habitats
number of different species and abundance
Genetic variation within each species
Ecosystem
Self-contained interacting community of organisms and the environment in which they live and interact
Kingdom Protocista
Single celled/group of similar cells
Kingdom fungi
Eukaryotic No photosynthesis (no chlorophyll) cell walls made of chitin (no cellulose) Heterotrophic nutrition (uses organic compounds made by other organsims as their source of energy) Reproduce by spores No cilia
Kingdom Plantae
Eukaryotic Multicellular Photosynthesis Cell walls made of cellulose Autotrophic nutrition
Kingdom Animalia
Eukaryotic Multicellular Heterotrophic nutrition Speciliased cells No cell wall
Autosomal linkage
Presence of 2 genes on the same autosome so that they are inherited together
(2 genes on the same chromosome)
Epistasis
1 gene affects the expression of another gene
Interaction of 2 genes at different loci
Gene expression
Regulatory gene-Promoter/operator/lacZ/lacY/lacA
lacZ=B-galactosidaes
lacY=permease
lacA=transacetylase
Regulatory gene
Gene that codes for protein that helps control gene expression of other genes
Structural gene
Gene that codes for protein that has a function within the a cell+used by the cell
Ethanol fermentation
Glucose-Pyruvate
Decarboxylated to ethanal
Reduced to ethanol
Using enzyme alcohol dehydrogenase
Lactate fermentation
Glucose-Pyruvate
Reduced to lactate
Using enzyme lactate dehydrogenase
Chloroplast pigments
Act as accessory pigments
Pass light energy to chlorophyll a
NADH
Coenzyme
Transports H
Allows reactions to become dehydrogenated
Seed germination
Seed absorbs water Giberellins are made by embryo+diffuse to the aleurone layer Synthesises amylase Hydrolyses starch to maltose Broken down to glucose
Gene control giberellins
No giberellins=DELLA protein cannot be broken down
PIF cannot bind to promoter
Amylase is not made
Le makes gibberellins
lele codes for non-functional enzyme(threonin) so no gibberellins are made)
Process of evolution by natural selection
A species shows genetic variation
Random mutation makes them fitter/better adapted to survive
They reproduce
Pass on advantegous alleles-increase allele frequency
Process of evolution by natural selection
A species shows genetic variation
Random mutation makes them fitter/better adapted to survive
They reproduce
Pass on advantegous alleles-increase allele frequency
DNA replication
Strands unwind
DNA polymerase attaches
Copies leading strand (5-3)
Copies lagging strand in small fragments
DNA ligase connects new nucleotides with phosphodiester backbone
Semi-conservative replication=New DNA has 1 new strand+1 old strand
Transcription
RNA polymerase attaches DNA unwinds Template strand is copied Non-transcribed strand is not copied RNA polymerase attaches nucleotides to growing mRNA with phosphodiester bond STOP message mRNA is released
Translation
tRNA transfers amino acids to ribosome Anticodon of tRNA binds to codon of mRNA Second tRNA enters 2 amino acids form peptide bond First tRNA leaves+another tRNA joins STOP message Polypeptide chain leaves ribosome
Explain why the offsprings dont present a 1:1:1:1 ratio
Some genes are inherited together (autosomal linkage)´
No random assortment
Recombinants due to crossing over
