topic one Flashcards
biological diversity
What are the conditions for life? (9 things)
-are made of cells
-need energy
-grow & develop
-reproduce
-adapt
-respond to the environment
-CHON
-produce waste
-exchange gas
What is an adaption?
Features that increase an organisms chance of survival in an environment
What is an ecosystem?
an environment where (biotic) organisms interact with (abiotic) components
What is a population?
Group of individual species which use a common area, eat similar things, and can reproduce together
What is a community?
Different species interacting. (only biotic things)
What is genetic diversity?
Variations between the same species. (blood type, bill shape, wing span)
Species distribution…
There are more species near the equator.
The 5 kingdom system
animals, plants, fungi, prostisa (single celled organisms), Monera (bacteria)
What is interdependence?
How species rely on other species. (food chains/webs)
Commensalism?
When one species benefits and the other is NOT harmed
Mutualism?
Both species benefit
Parasitism?
One benefits, the other species is harmed.
Inter species competition
When 2 or more species compete for the same resource. This helps limit the size of populations.
What is a niche?
Where it lives, what it eats, what eats it, effects of the species (its entire role)
What is resource partitioning?
Having slightly different roles. Ex- birds eating same thing from different parts of a tree
What is natural selection?
the environment will ‘select’ which individuals will survive. Ex- all flowers die so those rabbits that eat flowers will die while the others live
Inherited vs non-inherited
Heritable characteristics are characteristics that can be DIRECTLY passed from the parents to the offspring. (skin colour)
Non-heritable characteristics include learning something from your parents (becoming athletic like them etc)
Discrete vs continuous variations
Discrete- there are only 2 options
Continuous- there are more than 2 options
Binary fission
only for single-celled organisms- when a cell splits to form an identical copy
Budding
when the parent produces a smaller version of itself which eventually detaches from the parent
Spore production
Like seeds, however produced by the division of cells
Vegetative reproduction
The reproduction of a plant NOT involving a seed. (cuttings, runners, suckers, tubers)
Sexual reproduction
2 organisms, half your genetic material from one parent. Includes the joining of gametes. Male gametes=sperm cells Female gametes=egg cells or ova. when they unite it forms a zygote. The zygote continuously divides until it forms a embryo.
Where are the male/female gametes on a plant?
Male is the pollen which is on the stamen
Female is the ovules found in the pistil
What is pollination?
occurs when pollen is transferred from the anther of the stamen to the stigma of the pistil.
What is cross-pollination?
occurs when pollen from one plant is carried to the stigma of another plant
What is cross-fertilization?
occurs when pollen forms a long tube which grows down the style into the ovary
Advantages and disadvantage of sexual reproduction
Positive- Greater variation, variation helps a species adapt and survive
Negative- lot of energy, lot of time, smaller populations
Advantages and disadvantages of asexual reproduction
Positive- no specialized cells, one parent, many offspring quickly, good when environment doesn’t change
Negative- little genetic variation, less adaptability
what is DNA?
characteristics passed through one generation to another with a code. It is like a blueprint for all living things. DNA is located in the nucleus of the cell. Every DNA molecule contains the same chemicals
What is DNA made of?
It is a ladder shape. The rungs make variations. They are made up of 4 chemicals. Guanine (g) cytosine (c) adenine (a) thymine (t) The arrangement makes the genetic code of an organism
What chemicals are always paired together?
cytosine + Guanine
Adenine + thymine
What are chromosomes?
DNA is packaged into chromosomes. Every human cell contains 46 chromosomes. (23 from mom, 23 from dad) The 23rd pair is called the sex chromosome XX= female XY= male
What is a gene?
A segment of DNA containing instructions for a specific trait. Genes are on the chromosomes (many genes per chromosome) Genes come in pairs, one from each parent.
What is an allele?
Different forms of a gene are called an allele. (type of hairline)
Difference between dominate and recessive
Dominate- one that takes over (one expressed) Ex- a white cat and a black cat mate the offspring are black meaning black is the dominate trait.
Recessive- Weaker one- usually not visible
75% of the time it will be dominate 25% of the time it will be recessive
Heterozygous vs Homozygous vs homozygous recessive
Heterozygous- having 2 different alleles (dominant&recessive)
Homozygous- having 2 identical alleles
Homozygous recessive- both recessive alleles (having 2 recessive)
what is Mitosis?
A cell divides into 2 daughter cells, each containing same amount of chromosomes as the parent cell. Mitosis occurs during growth and tissue repair.
What is meiosis?
A type of division that produces 4 daughter cells. Each with only half the DNA as the parent cell. Meiosis occurs to produce gametes for sexual reproduction.
What is selective breeding?
Breeding organisms for specific features
Pure-bred vs Hybrid
Pure-bred- reproducing 2 organisms who have the same desired characteristic (tallXtall)
Hybrid- (tallXshort)
What is incomplete dominance?
When neither trait takes over. Ex- white + red flower = pink flower
What are causes of decrease in biological diversity?
-Habitat destruction
-agriculture
-urbanization causing pollution
-expansion of industry
-forestry
-hunting
-non native species
What is extirpation?
When a species is gone from a certain area but existing elsewhere.
Natural causes of extinction?
-over population
-disease
-over specialisation (pandas only eat bamboo)
-big events (volcanoes, storms)
2 examples of biotechnology
-artificial reproduction
-cloning
What is artificial insemination?
Artificial collection and injection of sperm from a male to a female.
What is in vitro fertilization?
Fertilization happening outside the body usually in a petri dish.
What is genetic engineering?
altering DNA of an organism
