Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/115

Click to flip

115 Cards in this Set

  • Front
  • Back
  • 3rd side (hint)
What are Mendel's 4 basic postulates?
1. All traits are controlled by two units (alleles)
2. The units seperate in meiosis
3. Law of Dominance
4. Law of Independent Assortments
Homologous
A pair of chromosomes with the same shape and contain the same genes.
Heterozygous
Having two different alleles for a given trait.
Homozygous
Having the same two alleles for a given trait.
Chromosomes
DNA all coiled up.
Gene
A segment of DNA that codes for a specific trait.
Allele
Variations of a gene.
Dominant
An allele that masks the presense of another allele of the same gene in a heterozygous combination.
Recesive
A trait whose expression is masked in a heterozygous combination.
Gamete
A haploid reproductive cell, either sperm or egg.
Gonad
The reproductive organ.
Zygote
The diploid product of the union of two haploids.
Fertilization
The union of the nucleus of an ovum and a sperm nucleus.
Meiosis
Two succesive cell divisions that produce gametes.
Diploid
A cell containing two sets of homologous genes (aka most of the cells in the body)
Haploid
A cell containing only one set of unpaired chromosomes.
F1 Generation
The 1st generation of hybrid offspring in a genetic cross.
F2 Generation
Offspring resulting from interbreeding the hybrid F1 generation.
Centromere
The specialized region of the chromosome that holds the replicated chromosome strands together, and that ataches to the spindle in mitosis.
Nondisjunction
The failure of a pair of homologous chromosomes or chromatid pairs to seperate during meiosis or mitosis.
Carrier
One who carries the recessive allele of a certain trait and does not express that trait but can still pass it on.
Asexual Reproduction
Reproduction without sex. ex: Amoebas
Clone
A linage of genetically identical individuals produced asexually.
Mutations - What/Why/Results (good/bad/neutral)
A mutation is a change in the genetic sequence resulting in a new allele.

Causes - Mutagens: UV radiation, smoking, randomness
Harmful - cancer, disease
Neutral - most of the time
Good - helps us study how DNA works and how genes are regulated; variation
Meiosis - results/where/importance/
oppurtunity for variation?
Meisis results in four gametes and occures in the gonads. Crossing over can occur before the last cell division.
Karyotype
A photograph of the choromosomes. Can indicate possible nondisjunction and gender.
Barre Bodies/X inactivation
In female mammals, one of the X chromosomes is turned off randomly in each cell. ex: calico cats
Genetic Imprinting
When the expression of a trait is influenced by which parent you inherited it from. ex: Huntington's
Cytoplasmic Inheritance
Since the mitochondria has its own DNA and only the mother passes down cell parts in the ovum, mitochondrial diseases can only be inherited from the mother, but she will give it to all her children.
Epistasis
When one gene controls whether another gene is expressed (it turns that gene on or off). ex: Labradors
Heterotroph
Cannot create their own food.
Autotroph
Can automatically make their own food.
Decomposer
Breaks down dead organisms and returns elements and energy back into the environment.
Producer
Produce their own food.
Consumers
Feed on other heterotrophs or autotrophs.
Herbivors/Carnivors/Omnivores
Plant/Meat/Both eaters (respectively)
Name the six main biomes
Tundra
Taiga
Deciduous
Grasslands
Desert
Rainforest
Primary Succesion
Starts from something living.
3 types of Symbiosis + examples
1. Mutualism: good<->good (lichens - protists + algae)
2. Parasitism good<->bad (ticks on dogs)
3. Commensalism good<->nutral (barnicles on whales)
Energy flow
Law of 10% - in living transfers of energy only 10% is transfered
Biogeochemical cycles
Any cycle that goes between biotic and abiotic. Includes the water, carbon, and nitrogen cycle.
Nitrogen Cycle
Nitrogen absorbing bacteria takes Nitrogen from the air and into our bodies to be used by protein.
Carbon Cycle
Basically respiration and photosynthesis.
Precipitation
Rain, snow, hail, sleet, etc.
Sublimination
Solid to Gas
Evapotransrespiration
Evaporation from plants
Condensation
Gas to liquid
Evaporation
Liquid to Gas
Water can be stored in...
Ice and snow/groundwater/freshwater/ocean
Infiltration
Water absorbed into the ground.
Aphotic Zone
The zone in the ocean where light is insufficient for photosynthesis.
Photic Zone
The shallow top layer of the ocean where enough light penetrates for photosynthesis to occure.
Greenhouse gas + effects
CO2 creats a blanket around the earth, trapping in heat.
Sources of carbon dioxide
Fossil fuels and deforestation
Causes/sources of Ozone depletion
CFC's from refrigeration, air conditioning, cleaning solvents, airasol, ect.
Acid Rain
Pollution from factories gets in the air and chemically reacts, later falling as acid.
Pathogens + examples
1.Virus - flu, cold, HIV
2.Bacteria - strep, sal manila, e coli, pink eye
3.Fungus - athlete's foot
4.Protist - malaria
5.Animal - worm
There are four
Toxins
Can be nonliving (heavy metals/chemicals) or living (botulism)
Non-specific Defences
1.Enzymes in saliva/tears/sweat
2.Skin
3.Membranes
4.Low pH of stomach
5.Fever
6.Inflamation
7.Phagocytes
There are seven
Specific Defences
Lymphocytes
B Cells-made in bone marrow, make large amounts of antibodies (proteins) that bind to the antigen on invader and disable or mark it for destruction
T Cells-made in the thymus, emit chemicals that keep immune system on track and build immunity
Phagocytosis
Phagocytes - like pac man
Luecocytes - more specific
Definition of Evolution
The change over time of populations of organisms from simple to complex.
Natural Selection
Directional-favors the weirdo
Stabalizing-remains at an average
Disruptive-favors extremes on both ends
Variation
Caused by mutations and Darwin assumes that variation exists in a population for evolution to occur.
Darwin
-Evolution happens in a process of natural selection
-variation must exist
-best adapted survive
Lamarck
aquired characteristics
Wallace
came up with the same theory as Darwin
Lyell
-geologist; Uniformitarianism (the same forces at work in the past are at work today)
Malthus
limiting factors + biological potention = carrying capacity
Hardy Weinberg model
p2 + 2pq + q2 = 1
p=dominant pq=hetero q=recesive

p+q=1
p=dominant allels q=recesive allels
Genetic Drift
Changes due to chance in the gene pool of a small population
Gene Pool
All the genes in a population at any one time
Bottleneck Effect
When the # of organisms is drastically reduced for a few generations, which leaves the population inbred.
Founder's Effect
Colonization by a small population that differs in genetic makeup from its source population.
Homologous Structures
Sharing a common ancestor even if the function differs (ex: human hand and dolphin fin)
Analogous Structures
Similarity in form or function but not the result of a common ancestor, indicates evidence of similar biological preasures (ex:incect wing and bird wing)
Co-evolution
The evolution of two species interacting with each other and reciprocally influencing each other's adaptations (ex: pollenators+plants; ants+acacia tree)
Definition of Species
Must be able to produce viable offspring.
First fossil evidence of life __ years ago.
3.5 billion
Earth is __ years old.
4.6 billion
Carbon Dating
-accurate up to 60 thousand years
-half life of about 5730 years
Potassium/Argon Dating
-used for more geological puroposes and rocks >100000 years old
Why was oxygen missing from the original atmosphere?
No photosynthetic organisms existed to create it.
Where did oxygen come from?
Photosynthetic life
Punctuated Equilibrium
Periods of alternating gradual and rapid evolution.
Gradualism
Constant, steady evolution over time.
Taxonomy
The classification of organisms in ways that reflect relationships and help distinguish types of organisms
Binomial Nomenclature
a two word naming system for each species, together these two words form the scientific name.
Heirarchial Classifications
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Six/Five Kingdoms
Eukaryotic
Protist
Plant
Fungus
Animal
Prokaryotic
Archea
Bacteria
Genus vs. Species
Species is more specific than Genus, both are italized and in latin, the Genus comes before the Species and is capitalized
Darwin's contribution to taxonomy
Developed a new system of relationships based on morphological observations
Comparitive DNA sequencing
Indicated how closely two organisms are related by recording how similar their DNA sequences are. Now used to group animals in taxonomy.
Three Domains
Archea-no nucleus; live in extreme environments
Bacteria-no nucleus;live everywhere; decomposer; disease
Eukaryia-nuclues+cell parts
Four kingdoms of Eukaryia
Protist-single celled
Plant-Autotrophical
Fungus-disease; decompose; food
Animal-invertabrates&invertabrates
Prokaryotic vs. Eukaryotic
A prokaryotic cell has no nuclues and lacks certain cell parts
Chloroplast
Photosynthesis; seperate DNA; located in plant cells only
Mitochondria
Respiration; seperate DNA; located in both plant and animal cells
Carbohydrates
-C,O,H (2:1 ratio)
-sub-unit=saccharide
Lipids
-C,O,H (not a fixed ratio)
-sub-unit=fatty acids+glycerol
Protein
-C,H,O,N, and sometimes S
-sub-unit=amino acids
-function: enzymes, hemoglobin, immune system, hair, muscles, ect.
Nucleic Acid
-sub-unit=phosphate+sugar+"base"
-function: DNA and RNA
Four DNA nucleotide/four RNA nucleotides
Thymine (Uracin in RNA)
Adenine
Guanine
Cytocine
Cell Membranes
Selectively Permeable, depends on polarity, size, and electric charge (charged/large molecules need special transport proteins)
Organic vs. Inorganic molecules
Organic molecules must contain carbon
Six main elements found in living organisms
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur
Diffusion
refers to the movement of molecules from and area of higher concentration to an area of lower concentrations
Osmosis
the movement of water down its concentration gradient
Turgor
the outward presure of a cell against its cell wall
What happens to an animal/plant cell in water?
An animal cell will burst and a plant cell will exprerience increased turgor
Endocytosis
Pulling something in through active transport
Exocytosis
Pushing something out through acive transport
Mitosis
Results in two identical daughter cells each with the same number of chromosomes as the parent cell.
Photosynthesis reaction
3CO2 + 3H2O -> C3H6O3 +3O2
Ribosomes
Small bodies composed of RNA and protein; catalyse the synthesis of cell proteins