General Terms Flashcards
molecule
atom + atom
compound
molecules w/ dif. types of atoms
element
single type of atom
glycogen
glucose storage for animals
starch
glucose storage for plants
cellulose
plant cell wall
chitin
fungi cell wall and arthropod exoskeleton
peptidoglycan
bacterial cell wall
Purines
Adenine, Guanine
Pyrimidines
Thymine, Uracil, Cytosine
Adenine-Thymine
2 hydrogen bonds
Guanine-Cytosine
3 hydrogen bonds
Euchromatin
loose genetic material (active, available for transcription)
Heterochromatin
tight genetic material (inactive, fully condensed)
Helicase
unwinds double helix
DNA Polymerase
adds nucleotides to an existing strand (5’ to 3’)
Ligase
brings together Okazaki fragments
Topoisomerase
cuts and rejoins helix
RNA Primase
catalyses the synthesis of RNA primers
Telomeres
at the end of strands to protect them
Simple diffusion
high to low, hydrophobic
Facilitated diffusion
high to low, hydrophilic
Active transport
low to high, hydrophilic (sodium, potassium, calcium, all ions, glucose) and hydrophobic
Endocytosis
phagocytosis and pinocytosis (requires ATP)
Osmosis
low solute to high solute
Vacuole
1 membrane, waste and material storage
Ribosomes
0 membranes, protein synthesis
Smooth ER
1 membrane, substance transport around cell
Rough ER
1 membrane, synthesise membrane proteins or secrete proteins
Golgi apparatus
1 membrane, sorts and packages proteins
Mitochondria
2 membranes, cellular respiration
Lysosomes
1 membrane, digests foreign substances and worn-out organelles
Centrioles
1 membrane, spindle fiber formation during mitosis
Nucleus
2 membranes, control center and genetic info
Nucleolus
1 membrane, ribosome synthesis
Cell membrane
1 membrane, regulates transport in and out of cell
Glycolysis
Cytoplasm, anaerobic
C6H12O6 + 2ATP -> 2 Pyruvate + 4ATP + 2NADH
Fermentation
2 Pyruvate reduced either to (2 Ethanol + CO2) or (2 Lactic acid) simultaneously 2NADH oxidised to 2NAD
Pyruvate Dehydrogenase Complex
Matrix, aerobic
Pyruvate into Acetyl CoA
NAD to NADH
CO2 released as waste
Kreb’s Cycle
Matrix, aerobic
Products: oxaloacetic acid, NADH, ATP, FADH, CO2
Electron Transport Chain
Inner membrane, aerobic
Energy phosphorylates ADP to ATP
polycistronic
prokaryote transcription
monocistronic
eukaryote transcription
Transcription
DNA to mRNA; nucleus
Translation
mRNA to proteins; cytoplasm/ribosome
tRNA
carries amino acids from the cytoplasm to ribosomes
start codon
AUG
stop codon(s)
UAA, UAG, UGA
codominance
heterozygote expresses both alleles (e.g. blood type AB)
incomplete dominance
mix of dominant and recessive alleles in phenotype
law of dominance
one allele is dominant over the other
law of segregation
two copies of a gene segregate and each gamete only gets one of the alleles
law of independent assortment
traits can segregate and recombine independently of other traits (linked genes violate this)
test cross
crossing with a recessive to determine genotype
SAT pedigree chart hints
1) recessive conditions skip generations
2) sex-linked if more males are impacted
Heterotroph Hypothesis
first living organism was a heterotroph
speciation
formation of a new species by evolution
divergent evolution
2 pops. of same species end up having dif. behaviours and traits (speciation is an extreme form of this)
convergent evolution
production of traits and behaviour between two separate 2 dif. pop/species (NEVER results in speciation)
analogous structures
Same structure, different ancestors (convergent evolution). Examples: wings in birds and insects
homologous structures
different structure, same ancestors (divergent evolution). Examples: human arm and whale flipper
vestigial structure
useless e.g. appendix in humans
central nervous system (CNS)
brain + spinal cord
cerebrum
conscious mind, voluntary actions
cerebellum
coordinates muscle movement & balance; coordination
medulla
involuntary actions; primitive region
hypothalamus
homeostasis
peripheral nervous system (PNS)
somatic or autonomic nervous system
somatic nervous system
voluntary; skeletal muscles (w/ acetylcholine)
autonomic nervous system
involuntary; sympathetic or parasympathetic nervous system
sympathetic nervous system
increases body activity; fight or flight; norepinephrine
parasympathetic nervous system
decreases body activity; rest or digest; acetylcholine
peptide-based hormones
bind to receptors on extracellular surface; turns enzymes on/off; faster; examples: insulin, prolactin, glycogen
steroid hormones
bind to receptors on intracellular level; modifies transcription; slower; examples: aldosterone, estrogen, testosterone
anterior pituitary gland
growth hormone, thyroid-stimulating hormone, follicle-stimulating hormone, adrenocorticotropic hormone, luteinising hormone, prolactin
(GH; TSH; FSH; ACTH; LH; Prolactin)
posterior pituitary gland
oxytocin, antidiuretic hormone (ADH)
thyroid gland
thyroxine, calcitonin
parathyroid gland
parathormone
adrenal medulla
epinephrine, norepinephrine
adrenal cortex
glucocorticoids, mineralocorticoids, sex steroids
pancreas
hormones (insulin and glucagon) and digestive enzymes (exocrine role)
gonads
testosterone, estrogen, progesterone
blood
50% plasma (mostly water + glucose, hormones, ions, gases, protein (albumin, fibrinogen, lipoproteins)) + 45% red blood cells (biconcave cell (w/ no nucleus) containing haemoglobin) + 5% white blood cells and platelets
white blood cells
phagocytes (eat) or lymphocytes (B-cells and T-cells)
B-cells
make antibodies, stick around as militia
T-cells
helper cells that help all lymphocytes divide and proliferate or killer cells that kill cells that have been infected
platelets
help blood clotting by secreting substances that ultimately convert fibrinogen to fibrin
type AB
universal recipient
type O
universal donor
arteries
away from heart; blood pressure is high; thick, muscular wall; branches into capillaries
capillaries
site of exchange; smallest blood vessels; slow and low; merge to form venules which merge to form veins
veins
return blood to heart; low pressure; muscle/skeletal contractions move blood; valves to ensure correct direction; no muscular walls
lymphatic system
network of vessels that recapture fluid and filters it with lots of white blood cells (via lymph nodes) and returns it to blood
blood pathway
vena cavae- right atrium- right ventricle- pulmonary artery- lungs- pulmonary veins- left atrium- left ventricle- aorta- body- (vena cavae)
atrioventricular valves (AV)
tricuspid and mitral
semilunar valves (SV)
aortic and pulmonary
inspiration
chest cavity increases, decrease in air pressure, air rushes into lungs, diaphragm contracts/flattens out/lowers
expiration
chest cavity decreases, increase in air pressure, air rushes out, diaphragm relaxes/curves upwards
pH of blood
7.4
vitamin A
retinal for slight
vitamin B
cellular respiration, DNA replication
vitamin C
collagen
vitamin D
calcium absorption
vitamin E
protects cell membranes
vitamin K
blood clotting
iron
hemoglobin
calcium
strong bones, teeth, and for muscle contraction
iodine
thyroxine
urine
urea acid (amino acids) + uric acid (nucleic acids) + creatinine (muscle metabolism)
bones
rigid substance made up. of cells embedded in a solid calcium-phosphate matrix. Supports the body, protects soft organs, produces blood cells, stores minerals
cartilage
ends of bones at the joins; shock absorber to prevent bones from rubbing against each other
muscle components
actin + myosin = sacromere -> myofibril -> muscle cell/fiber -> fascicle => whole muscle
epidermis
surface; dead skin cells
dermis
blood vessels, nerves, hair follicles, glands
hypodermis
protects and insulates body // fat
endoderm
internal structures and organs
mesoderm
bones, blood vessels, muscles, heart and non-glandular organs
embryonic development stages
gametes - fertilisation - zygote - cleavage - morula - blastocyst - implantation - gastrulation - neuralation - fetus - birth
cuticle
waxy layer under epidermis that protects leaf and traps water
palisade layer
just under surface of leaf: most photosynthesis occurs here
spongy cells
beneath palisade: important for gas exchange, also carries out photosynthesis (but less)
stomates
gas exchange; controlled by guard cells
light-dependant reactions
membranes of thylakoids; water is split into hydrogen ions and oxygen; solar energy converted into usable energy (NADPH and ATP)
light-independant reactions
stroma of chloroplast; calvin cycle/carbon fixation, ribulose biphosphate into 2x glyceraldehyde-3-phosphate
xylem
transports water and minerals; tracheids and vessel elements
phloem
transports products of photosynthesis; sieve cells and companion cells
root hairs
increase surface area for absorption of water and minerals
stamen
anther + filament
pistil
stigma + style + pollen tube + (ovary + ovule)
anther
makes pollen w/ microspores
ovule
forms megaspores (which can divide to form eggs and polar bodies). Becomes seed in reproduction process.
endosperm
food storing tissue that surrounds the embryo
ovary
becomes a fruit in reproduction process
fixed-action patterns
preprogrammed stereotypical behaviour triggered by specific stimuli
imprinting
recognition of some object as “mother”
classical conditioning
neutral signal leads to a reflex
operant conditioning
reward/punishment system
insight learning
ability to approach new situations and figure it out -> reasoning
phototropism
towards light
negative gravitropism
stem upwards
positive gravitropism
root downwards
thigmotropism
along a surface
circadian rhythm
when a biological clock makes an organism do something on a daily basis.
symbiosis
different species sharing a living space
mutualism
both organisms benefit
parasitism
one benefits, one harmed
commensalism
one benefits, one is neutral
abiotic
non-living
biotic
living
biological organisation
cell - tissue - organ - organism - population - community - ecosystem - biome - biosphere
population
group of individuals in a particular area that can interbreed and therefore share the same gene pool
community
group of populations that live in a particular environment, interact but not reproductively
niche
a way an organism lives in its environment
competition
two dif. organisms with the same niche
coevolution
alternate evolution of two species based on their interactions with each other
decomposers
bacteria/fungi; eat the dead
ecological succession
gradual change in an ecological community
pioneer organism
first to start living in the previously uninhabited area
climax community
succession ended, stable community
ecosystem
community + the environment it lives in
transpiration
water vapor escaping stomates
evaporation
water vapor escaping body of water
respiration
carbon returned to atmosphere
photosynthesis
carbon removed from atmosphere
legumes
plants with their own nitrogen-fixing bacteria
biomes
large areas classified by their ecosystems
the tundra
permafrost, deep root growth is difficult
the taiga
coniferous forest
the deciduous forest
lots of rain, hot and cold seasons, trees drop and regrow leaves
the grasslands
low-growing plants, fertile soil, insects are dominant herbivores.
tropical rain forest
highest rainfall, greatest diversity, very tall trees
the desert
driest, flora and fauna adapted to arid environment.
intertidal zone
marine; where land and water meet
neritic zone
marine; extends from intertidal zone to continental shelf
oceanic zone
marine; open ocean, very little nutrient concentration
pelagic
open water
bethic
ocean bottom
abyssal zone
marine; deep under oceanic zone; no light
photic zone
light for photosynthesis
aphotic zone
no light for photosynthesis, nutrients come from photic zone
littoral zone
freshwater; near shore, many plants, wide variety of consumers
limnetic zone
freshwater; farther from shore, light for photosynthesis, primary consumers thrive
profundal zone
freshwater; underneath limnetic zone; aphotic region; sinking nutrients; primary consumers are food for secondary consumers
human impact
greenhouse effect, o-zone depletion, acid rain, desertification, deforestation, pollution, reduction in biodiversity
adaptive radiation
numerous species from one common ancestor
tendons
bone to muscle
ligaments
bone to bone
chromosomal disorders
down syndrome, klinefelter’s syndrome
autosomal recessive disorders
PKU, cystic fibrosis, Tay-Sach’s
autosomal dominant disorders
huntington’s disease
sex-linked recessive
color blindness and hemophilia
hardy-weinberg principle
p^2 + 2pq + q^2 = 1
p^2 = homozygous dominant q^2 = homozygous recessive 2pq = heterozygous
silent mutation
not visible in phenotype because the protein product remains unchanged
zooplankton
primary consumer in an aquatic ecosystem
directional selection
one extreme favoured
- peppered moths
stabilising selection
neither extreme favoured
disruptive selection
both extremes favoured
- balanced polymorphism
evidence for evolution
- fossil record
- comparative anatomy + biochemistry + embryology
- molecular biology
- biogeography
types of natural selection
stabilising selection, diversifying or disruptive selection, and directional selection
sources of variation in a population
mutation, genetic drift and gene flow
single point mutation
introduces a new allele in the population
genetic drift
change in the gene pool due to chance
- bottleneck effect
- founder effect
the bottleneck effect
natural disasters reduce the population, and therefore the gene pool. Certain alleles may be then under or overrepresented compared with the original population.
the founder effect
when a small population breaks away from a larger population to colonise a new area, rare alleles may be overrepresented
gene flow
movement of alleles into or out of a population; can result from migration
Hardy-Weinberg factors that MUST be true if a population is stable…
1) Population is large
2) Population is isolated
3) No Mutations
4) Mating must be random
5) No natural selection
Forms of Isolation
1) Geographic Isolation
2) Polyploidy
3) Habitat Isolation (species encounter each other rarely in their area)
4) Behavioural Isolation (firefly example)
5) Temporal Isolation (if a flower becomes sexually mature earlier)
6) Reproductive Isolation (anatomical incompatibility: Great Dane x Chihuahua)
Patterns of Evolution
1) Divergent evolution
2) Convergent evolution
3) Parallel evolution
4) Coevolution
5) Adaptive radiation
Theories of Evolution
1) Gradualism
2) Punctuated Equilibrium
3) Spontaneous Generation
