Biodiversity Flashcards
What is Biodiversity?
The number and variety of organisms
Why is Biodiversity important?
Humans cannot fully comprehend what an organism contributes to the ecosystem and even getting rid of one organism can have major side effects. Additionally, without biodiversity we would have species that wouldn’t respond to changes in the environment and cause life on earth to die out
What are the 3 levels of biodiversity?
Genetic (Variation of genes within a species) Species (Variation of species within an ecosystem) and ecological (variation of ecosystems within our planet)
Explain the taxonomy pyramid
Species:
A group of organisms with similar characteristics that are capable of inbreeding
The offspring of two organisms that belong to the same species are mostly fertile
Genus:
A group of organisms with similar characteristics and encompasses a few, maybe hundreds of species
Family:
A group of organisms with similar characteristics and encompasses a few genuses
Order:
A group of organisms with similar characteristics and encompasses a few families
Class:
A group of organisms with similar characteristics and encompasses a few orders, e.g. mammals, insects
Phylum:
A group of organisms with similar characteristics and encompasses a few classes, usually based on body structure characteristics
Kingdom:
A group of organisms with similar characteristics that are dramatically different from the other kingdoms, consisting of Plants, Animals, Protists and Fungi
Domain:
One of the 3 fundamentally different branches of life, which include Eukarya (has a nucleus) Bacteria and Archaea
What are species?
A group of organisms that share many characteristics that are capable of interbreeding and creating fertile offspring
What is speciation?
The development of a species into several new species
How are unique traits essential to an organism’s survival?
Adaptations (structural, physiological or behavioral) can help a species thrive in an ecosystem
Different types of adaptations
Structural: Physical body part
Behavioral: How an organism acts
Physiological: Producing new chemicals and hormones
What is a local example of the importance of biodiversity?
The lodgepole pine was nearly wiped out by the mountain pine beetle whereas places with greater biodiversity do not suffer the same huge losses
How would a scientist measure biodiversity?
Through a diversity index that is calculated by total species/total organisms
What is an organism’s niche comprised of?
Its location and what it does
What is competition and how does it show the importance of biodiversity?
Competition is fighting for a resource by different animals (of the same species or no) and variations between them give one an advantage
What are broad niches and generalists?
A broad niche is a niche fulfilled by a generalist, an organism with adaptations and variations to allow it to survive in various different environments
What are narrow niches and specialists?
A narrow niche is a niche fulfilled by a specialist, an organism with adaptations and variations to allow it to survive in a specific environment
What is a symbiotic relationship?
A long-term dependency of one organism with another
What is mutualism?
A symbiotic relationship in which both organisms benefit
What is commensalism?
A symbiotic relationship in which one organism is not affected while the other organism benefits
What is parasitism?
A symbiotic relationship in which one organsim is harmed while the other benefits
What does interspecies and intraspecies mean?
Interspecies means between species and Intraspecies means within the same species
What is the term for a trait that is able to be passed on from parent to offspring?
Heritable
What is asexual reproduction?
A form of reproduction in which the organism creates an offspring by itself
What are the advantages and disadvantages of asexual reproduction?
Not needing to find a mate, and occurring quite quickly. However, there is less genetic diversity
What is binary fission?
A form of asexual reproduction where the original cell splits, or mitosis for single-celled organisms
What are asexual spores?
A form of asexual reproduction in which a bunch of spores get scattered around. Also called plantlets
Users of asexual spores
Fungi, Ferns, Algae
What are zoospores?
A form of spores that have flagella
What is vegetative reproduction?
A form of asexual reproduction in which plants use the meristem function to reproduce. Examples are runners(horizontal stems extending to create new plants), layering(plant bends down and makes new plant), cuttings(put part of plant in water to grow), grafting(putting a plant onto another plant) and many more
What is the meristem function?
A trait in some plants that allows them to grow back any part of the body, allowing them to duplicate with the help of stem cells
What is budding?
A form of asexual reproduction that happens when a bud grows near the base of an organism that detaches when fully grown
What is sexual reproduction?
When both parents supply genetic material
What are zygospores?
Spores with genetic material from two parents
What is bacterial conjugation?
Directly transferring genetic material that can be a form of sexual reproduction between cells
What are angiosperms?
Flowering plants
What are gymnosperms?
A plant that reproduces through an exposed seed ex. pine cones
What is a zygote?
The first cell of an organism
Describe a flower:
See image 9
Describe a plant seed/embryo
See image 10
How does pollination occur in flowers?
Pollen from the anther lands on a stigma, through the newly formed pollen tube into the egg
How does a flower seed mature?
After being fertilized, the petals die off, leaving the embryo and one or two cotyledons which will germinate when conditions are right
How does external fertilization work?
Both parents sit in water and release gametes at the same time and some end up being fertilized
Why is it useful for plants reproduce sexually and asexually?
They reproduce sexually if possible but asexually if conditions are not good
Why is internal fertilization better than external?
Higher fertility rate
What is heredity and genetics?
The passing on of traits is heredity and that branch of science is genetics
What is continuous variation?
Something that has a range of possibilities for traits ex height
What is discrete variation?
Some trait that has a limited number of possibilities ex rolled tongue or no
What is a dominant trait?
A trait that shows up in offspring, even if there is only one copy represented by a capital letter
What is a recessive trait?
A trait that does not show up in offspring unless both parents have it, represented by a lower case letter
What is the difference between heterozygosity and homozygosity?
Heterozygosity is a dominant and a recessive while homozygosity is both same
What is incomplete dominance?
Where a trait combines with another weaker trait to make a shifted phenotype ex different color wool in minecraft sheep
What is co-dominance?
Both traits show up in offspring
What are mutations?
Changes to DNA
What are mutagens?
Something that can cause mutations
What happens if too many mutations happen?
Cancer or new species
What is deoxyribonucleic acid?
DNA is a molecule discovered by Johann Miescher in 1868 that can reproduce, move from parent to offspring, and control cells. The structure was later discovered by Watson and Crick in 1953 with the help of Rosalind Franklin
What are chromosomes?
Many strands of DNA clumped together
What are the 23 pairs of chromosomes?
22 pairs and an x and y sex cell that does nothing in somatic cells
What is an allele?
A form of the same trait
What is a genotype?
Genetic code of traits
What is a phenotype?
Physical representation of genes
What is the structure of DNA?
Much like a coiled ladder (double helix)
What are nucleotides?
Smaller building blocks of DNA that are made of phosphates, sugar and a nitrogen base: A(adenine) T(thymine) G(guanine) and C(cytosine). A and T fit together and C and G fit together (see image 11)
What is the genetic code?
A set of code in DNA that tells it how to control the production of proteins in a cell. A section of DNA that has code for a specific protein is a gene
How many chromosomes do each human cell contain?
46, or 23 pairs
What are the 2 types of cell division?
Binary fission and the creation of sperm and egg cells (mitosis and meiosis)
What are somatic cells?
Cells that are not sperm or egg cells
How many cells are in the human body?
60-100 trillion
What are gametes?
Sex cells or sperm and egg cells
How does a cell divide?
It copies every chromosome and divides them in a process called mitosis. Thus, the two cells are exactly the same
How is gender determined?
The chromosome is xy in males and xx in females, and is determined by what chromosome the successful sperm carries
How does meiosis work?
A germ cell divides itself into 4 gametes, each having 23 so the zygote can have 46 chromosomes. This technique creates 2 to the 23rd power different combinations of chromosomes due to the different chromosomes assorting themselves into 2 groups and combined with another gamete from another parent, significantly increases biodiversity
What is genetic engineering?
Artificially creating DNA
What are biotechnologies?
Moving genes from one organism to another
How do biotechnologies help in medicine?
Many different ways, including making a bacteria produce insulin
What are transgenic animals?
Animals that have been genetically tampered with
What are GMOs?
Genetically engineering organisms to create better and more food
What are domestic animals?
An animal tamed or bred by humans to perform a certain task
What is artificial selection/selective breeding?
Breeding animals to get the traits people want
What is the theory of natural selection?
- All organisms produce more offspring than can possibly survive
- There is incredible variation within each species of organism
- Variations that increase an organism’s chance of survival are passed on
- Over time, variations are passed on to lead to changes in the genetic characteristics of a species
What is natural selection? (Not the theory)
The process in which favorable traits become more common and unfavorable traits become less common in a certain species.
What is the sixth extinction?
The theory that humans may be causing the 6th great extinction of life on our planet, with estimates on 70 species disappearing per day
What areas of the world generally support more biodiversity?
Humid, warm climates
What is a bioindicator species?
A species to look at to determine the health of an ecosystem ex grizzly bears and wolverines
Why is habitat loss such a large problem in tropical developing countries?
Trees are used for firewood, and land that is turned into farms quickly run out of nutrients as a result of the land’s dependence on the above ecosystem. As a result, the land soon becomes infertile and more forest has to be cleared
What are some examples of extinctions caused by humans?
dodos, passenger pigeons, etc.
How do zoos help with biodiversity?
They are a near-perfect sanctuary and can contain the last few species of some animals
What are seed banks?
Places to store seeds to improve genetic diversity in plants
How do global treaties help biodiversity?
They prohibit the hunting of some endangered species
How many base pairs are in a human cell?
Roughly 3 billion
What are the steps of mitosis/meiosis?
Interphase: Cell prepares for mitosis, cell grows. G1 is just growing, S is duplicating chromosomes into sister chromatids, and G2 is synthesizing proteins and organelles
Prophase: Compacts chromatin into chromatids, because in interphase they were unravelled. Exchange genes in synapsis only in meiosis I, homologous chromosomes come together only in meiosis I
Prometaphase: Nuclear membrane breaks down and chromatids are set free. Kinetochore Microtubules (little strings), also called spindle fibers, attach themselves to the chromatids and anchor themselves at opposite ends of the cell
Metaphase: Chromatids line up in a central line called the metaphase plate. In meiosis, double file line
Anaphase: Chromatids are pulled apart at the centromeres by shrinking microtubules, the chromatids are now called chromosomes, and start shrinking into 1 point
Telophase: Reformation of cell structures
Cytokinesis: Proteins cut off cell membrane and split it
Haploid vs diploid
Haploid is half the chromosomes, diploid is same
Chromatid vs Chromatin vs Chromosome
Chromatid: A chromosome during reproduction (only a line no matter what)
Chromosome: A little piece of genetic information, and during reproduction it is just 2 chromatids (can be line or x)
Chromatin: Unraveled chromosome
What is heterozygosity and homozygosity?
Two of the same alleles or 2 different alleles, respectively
Types of vegetative reproduction?
grafting, cutting, runners, rhizomes, tubers, etc. This is all due to the meristem function, or unspecialized cells that can grow into anything
What is vegetative reproduction?
A plant grows and grows and if cut, both survive
3 types of diatomic atoms (what does hydrogen bond with?)(In DNA)
Nitrogen, Oxygen, Fluorine. Only Nitrogen and oxygen in DNA
What is a karyotype?
Diagram of all chromosomes
Ex situ conservation
Protecting organisms not in their original habitats
In situ conservation
Protecting organisms in their original habitats
In vitra fertilization
Outside 2 parents fertilization, usually in a petri dish
Where must animals perform sexual reproduction?
Internally or in water
What is extirpation?
Where a species is no longer found in a certain area
How many genes are in a human cell?
30000
How many base pairs are in a gene?
3000
