Lab Practical 1 Flashcards
what do humans categorize?
- colors
- the vast diversity of life
taxonomy
- devoted classification of organisms
dear king phillip came over for good soup
domain, kingdom, phylum, class, order, family, genus, species
evolution
- similarities are due to common ancestry, but there are always exceptions to this
carolus linnaeus
- biologists use a taxonomic system that was devised by Linnaeus
- a hierarchal system group organisms into more inclusive categories from species up to kingdom
fixity of species
the belief that the earth and all the organisms on it had been created suddenly in their present form
common ancestor
- individuals have inherited traits from the same ancestor
- the greater the resemblance between two species, the more recently they diverged from a common ancestor
what were Mendel’s key findings?
traits are passed down in discrete units called genes, rather than via blending inheritance
genotype
alleles that an organism has at a gene locus
phenotype
observable trait that is determined by the genotype
autosomal dominant
traits where only one copy of the allele is needed for the trait to be displated
autosomal recessive
traits where both copies of the allele must be the same for the trait to be displayed
sex-linked trait
traits whose genes are located on the sex chromosome, usually the X
- hemophilia (recessive), no alleles on Y,
what are two principles of inheritance?
principle of segregation and principle of independent assortment
principle of segregation
pairs of alleles in a gene separate during the production of sex cells (meiosis), such that each gamete (egg or sperm) has just one allele (haploid)
principle of independent assortment
genes that code for different traits sort out independently of each other during gamete formation
what is evolution?
the change in allele frequency in a population over time
allele frequency
the fraction of individuals in a population who have a certain allele
microevolution
guided by variation within a population
what causes evolution?
- mutation
- selection
- gene flow
- genetic drift
genetic drift
random change results in a change in allele frequency in a population
- types: genetic bottleneck and founder’s effect
mutation
the spontaneous change in one allele into another
gene flow
migration, the influx/outflow from/to other populations
selection
natural selection proposed by Darwin. conditions of the environment cause nonrandom elimination of some individuals’ alleles in the next generation, either because they were unable to successfully reproduce or had no offspring that were able to successfully reproduce
what are the planes of the body?
sagittal plane, coronal plane, and transverse
human dentition
each quadrant has 2 incisors, 1 canine, 2 premolars, and 3 molars
- total of 32 teeth
osteology
study of bones and teeth
skeleton roles
the support system for the rest of the body—making
movement possible, and protecting vital organs like the heart, lungs, and brain—a new understanding is emerging of bones as an important, dynamic organ of the body.
above
superior
toward the head
cranial
towards the belly
ventral
towards the front
anterior
towards the midline
medial
region of limb closer to trunk
proximal
below
inferior
towards the tail
caudal
towards the back
dorsal
towards the back
posterior
away from the midline
lateral
region of limb away from trunk
distal
strepsirrhines
lemurs and lorises
haplorhines
monkeys and apes
platyrrhines
new world monkeys
catarrhines
old world monkeys and apes
cercopithecoids
old world monkeys
hominoids
apes (including humans)
primate classification
what are the general primate traits?
- majority have a dental formula of 2.1.3.3. or 2.1.2.3
- more orthognathic
- flat nails rather than claw on the big toe
- postorbital bar
- opposable thumb
- forward facing (convergent) orbits
what are the characteristics of the strepsirrhines?
- long snout
- unfused mandibular symphysis
- unfused frontal bone
- postorbital bar but no postorbital plate
- grooming claw on second digit of foot
- tooth comb
what are the characteristics of the haplorrhines?
- short snout
- fused mandibular symphysis
- fused frontal bone
- postorbital plate
- no grooming claws
- no tooth comb
what are the exceptions the group tarsiers of the haplorrhines have?
- no fused mandibular symphysis
- 2 grooming claws
what are the characteristics of catarrhines?
- old world monkeys and apes
- no prehensile tails
- dentition of 2.1.2.3
- downward-facing nose
what are the characteristics of platyrrhines
- new world monkeys
- some have prehensile tails
- 2.1.3.3
- flat nose
what are the characteristics of cercopithecoids?
- narrow nose
- narrow palate
- tail
- smaller brains
- bilophondont molars
what are the characteristics of hominoids?
- broad nose
- broad palate
- no tail
- larger brains
- Y-5 molars
prosimians
lemurs, lorises, and tarsiers
anthropoids
monkeys, apes, and humans
symplesiomorphy
shared ancestral traits
synapomorphy
shared derived traits