Part 1 Flashcards
Definition of biology?
The study of living things
Definition of variations?
visible differences in behavior or physical traits observed between all living organisms
Difference between Interspecific and Intraspecific variations?
Interspecific - Differences between different species (dog/cat)
Intraspecific - Differences between individuals of the same species (german shepherd/golden lab)
Definition of biodiversity?
It is a measurement of the interspecific and intraspecific variation that exists within an ecosystem, eg. the more variations that are observed, the greater the biodiversity
Definitions of adaptations?
Variations in physical and behavioural characteristics may allow organisms to better survive in their particular environment
Two types of adaptations?
Structural and behavioural
Definition of natural selection?
The process of organisms with favorable adaptations reproducing better than those with, passing on their genes
How do you assess the relative health of an ecosystem?
- A method called the diversity index
- # of different species/total # of organisms in area
Definition of a niche?
A role an organism fulfills in their environment
Generalists vs specialists?
Generalist - Occupy a broad niche because of their non-specific adaptations (wolves, hares)
Specialist - Occupy a narrow niche because of their specific adaptations (koalas, pandas)
Two types of competition in nature?
Interspecific competition - Occurs between different species
Intraspecific competition - Occurs between members of the same species
The three types of symbiotic relationships?
Mutualism (both benefit), Commensalism (one benefits), parasitism (one benefits at the expense of the host)
Difference between parasites and predators?
Predators kill their prey to consume them
Parasites avoid killing their host because they would have to find a new one
Definition of heritable traits?
Characteristics that are passed on from parents to their offspring are said to be heritable
How are heritable traits passed down?
Through genes, the genetic material contained within the nucleus of every cell in your body
Two types of reproduction?
Asexual and sexual reproduction
Four main types of asexual reproduction
- Binary fission
- Asexual spores
- Budding
- Asexual reproduction in plants (Vegetative reproduction)
Define binary fission
- Used by single-celled organisms such as amoeba
- The cell duplicates its genetic material and splits into two genetically identical cells
- All offspring are identical
Define asexual spores
- Used by fungi
- Organism’s genetic info is copied in each single-celled spore, which are released and spread through wind, rain, etc
- Some spores, known as zoospores, have a flagella (a tail-like structure) to help them move around
- Spores grow to become an exact copy of parent
Define budding
- Used by small animals like sea sponges and hydras
- As the organism grows, one of its cells will form a bud and start to grow on its own
- When the bud has completely developed, it detaches
- The bud is an exact copy of the original organism
Define vegetative reproduction
-
What are gametes?
Egg and sperm
What is a zygote?
single fertilized cell created by the joining of a sperm and egg
Zygospores vs Zoospores
- Zygospores are a thick-walled structure and can only be formed by the fusion of an egg (female gamete) and a male gamete
- Zoospores are an asexual spore that are flagellated (have a tail) and do not need a mate
Bacterial conjunction
- Some bacteria are able to simply transfer genetic material directly from one cell to another
- No new cell is formed (so technically it is not reproductive), but both bacteria involved in the transfer end up having a new combination of genes
- Bacteria with this mixture of genetic info will eventually reproduce using binary fission, resulting in many duplicates of the new bacteria
- Allows for variation and new inherited traits to be passed on
Gymnosperms vs Angiosperms
GYMNOSPERMS
- Used by coniferous trees like spruce, pine and fir.
- Do not form flowers or fruit; instead, seeds are produced inside cones
ANGIOSPERMS
- Used by flowering plants.
- Produce seeds that are covered by fruit.
- Seed is formed when the pollen (sperm) and the ovule (egg) unite during pollination
Parts of the stamen
- Anther (produces pollen)
- Filament (holds up anther)
Parts of the Carpel/Pistil
- Stigma (sticky lip outside of tube, catches pollen)
- Style (tube that brings polen down to the ovary
- Ovary (Where ovules are found)
Two types of fertilization?
Internal (egg is fertilized inside the body)
External (egg is fertilized outside the body)
What is cleavage?
Cell division of the zygote to create a multicellular being
What are genes?
the sections of chromosomes or strands of DNA that code for different traits
What are heritable traits?
Traits that are passed down from the parents to the offspring
What are the two types of genetic varitation + example of each
- Discrete (variations with limited possibilities, either you have it or you don’t) eg. Widows peak, hitchiker’s thumb
- Continous (variations with a range of possibilties) eg. Height, hair color
Define epigenetics?
The study of how environmental factors influence gene expression
How many chromosones do humans have?
46 (23 pairs)
What are alleles?
two possible forms of a gene
Dominant vs resessive allele
The dominant allele will be the one that is expressed
The ressesive allele is not expressed, but the coding for it will still be passed down in DNA
Genotype vs Phenotype
Genotype - the alleles that you have
Phenotype - The traits you express
Define mutation
A random error in DNA
Define mutagen
A chemical or physical agent that can induce changes in DNA (lead paint, UV rays, ect.)
What base pairs go together?
A and T, G and C
Phenotype vs Genotype
Genotype - the alleles you have
Phenotype - the genes you express
