Biology

Created by

Jiya

Cards (41)

Biodiversity  
Sum of all living organisms (found everywhere)
Species Diversity  
Number of different species within an ecosystem
Genetic Diversity 
range of genetic characteristics within a single species
Alleles  
Different forms of genes (usually represented by letters)
Upper case letters are dominant
lower case letters are resessive
Genotype 
specific combonation of gene you have
Phenotype 
The physical representation of the genotype
E.G: code for rabbits, F = black fur
Genetic Drift  
an increase or decrease in allele frequency due to a chance event
Natural selection
organisms with favourable traits who are more likely to survive
naturally occurring
mutation 
changes in an organisms genetic code or DNA
gametes 
egg or sperm cells
Gene flow 
increase or decrease in alleles frequency due to immigration or emigration of organisms
Evolution 
Change in species over time, increase in abilities or organisms, adaptation due to environmental influence
Adaptation  
a structure or behaviour that helps an organism survive in its environment
Meiosis 
crossing over of chromosomes
chromosomes 
long strands of genetic information located in the nuclei of cells
every single chromosome is made of DNA
human body has 46 pairs, 23 pairs
karyotype 
XX for females and XY for males
Genotypes (Flip card) 
YY = homozygous dominant (all capital)
yy = homozygous recessive (all lower case)
Yy = heterozygous (one capital, one lowercase)
How many chromosomes in diploid and haploid
Diploid = 46 chromosomes
Haploid = 23 chromosomes
Homologous chromosomes 
Matching pairs of chromosomes (1 from mum and 1 from dad)
Variation  
species different from each other
4 conditions for natural selection
reproduction rate
inheritance patterns
variation of characteristic
variation in fitness of organisms
biotic factors 
predators, disease, competition, prey and mating patters
abiotic factors  
temperature, shelter, sunlight, water and nutrition. (Non living)
artificial selection  
'selective breeding'
(different dog breeds)
selected by humans
Lamark theory of evolution  
animals can change their traits (not by birth) and their offspring will inherit the same trait
Eg: if a giraffe stretched its neck to reach high leaves, its offspring would inherit longer necks
Darwin's theory of evolution
animals change over time to better fit their environment
Darwin's six factors
Overproduction
genetic variation
natural selection
competition
adaptation
speciation
Gene pool 
total sum of genes, all their alleles of individuals in population
system group (in order)
kingdom, phylum, class, order, family, genus, species
Kingdom
how they gain nutrition and cells
5 - anamilia, plantae, fungi, protista, monero
species
group of similar individuals that interbreed to produce fertile offspring under natural conditions
Hybrids - unable to breed
Speciation 
The process by which one species splits into 2 or more separate species
Isolation  
different groups of the population are prevented from interbreeding
prevent gene flow from population 1 going to another
Allopatric Speciation
when 2 same species become isolated from each other due to geographic barrier
Sympatric Speciation  
organisms become reproductively isolated & diverge into new species without any physical separations
Reproductive Mechanisms of Isolation
Geographic
Ecological isolation
Temporal "time" isolation
Behavioural Isolation
mechanical isolation
gametic isolation
Selective Pressure  
Biotic or abiotic influence that affects a population; influencing its survival
convergent evolution 
organisms not closely related evolve similar traits while adapting to a similar environment
divergent  
organisms from the same common ancestor evolve resulting in new species
parallel  
spices acquire similar characteristics while evolving together