Unit 1 Flashcards
Biology
The scientific study of living things.
Eukaryotes
cells that have a nuclear membrane
Explain why humans use classification systems and the limitations of the systems we use.
We classify to be able to simplify by groups. Are limitations used to help us understand relationships between organisms; although it is not part of the real world.
Define hierarchy of structural organization
Life is highly organized from the simplest atoms to complex multicellular organisms. Along this hierarchy of structure, atoms form molecules that are used to form organelles, which in turn form the functional subsystems within cells. Cells are organized into tissues, and then into organs and organ systems such as the nervous system. This organization extends beyond individuals to populations, communities, ecosystems, and the entire biosphere.
Examples of each hierarchy level
Cellular Level = Atoms; Organismal Level = Organs; Populational Level = Ecosystems.
Explain the overall relationship among hierarchy levels with respect to complexity
Along this hierarchy of structure, atoms form molecules that are used to form organelles, which in turn form the functional subsystems within cells. Cells are organized into tissues, and then into organs and organ systems such as the nervous system. This organization extends beyond individuals to populations, communities, ecosystems, and the entire biosphere.
Explain how using the hierarchical system can help us understand life.
Hierarchy helps us simplify the complexity of life so we may better understand the relationships.
What is the goal of systematics?
To understand the history of ancestor-descendant relations that unites all forms of life on Earth.
What kind of characteristics reflect common ancestry?
Homologous characteristics
What is the major assumption of systematics?
That the greater the number of shared homologous characteristics between two species, the more closely they are related.
What kinds of information can we get from phylogenetics trees?
It shows us the relationship between groups of organisms.
How are organisms grouped in taxonomy?
They are grouped by shared characteristics.
State the assumptions underlying taxonomic classification.
That similar organisms have properties in common and that similar organisms are more closely related to each other than organisms in different groups.
Name the 5 kingdoms, the organisms found in each and the major characteristics of each kingdom.
MONERA = All prokaryotes like bacteria PROTISTA = Single celled organisms like algae PLANTAE = Multicellular eukaryotes autotrophs like plants FUNGI = Multicellular heterotrophs that absord nutrients like mushrooms ANIMALIA = Multicellular heterotrophs the ingest other organisms like humans
List 7 main levels of taxonomic classification.
KINGDOM, PHYLUM, CLASS, ORDER, FAMILY, GENUS, SPECIES
Be able to write out the taxonomic classification for one species.
KINGDOM: Animalia PHYLUM: Chordata CLASS:Mammalia ORDER:Primates FAMILY: Hominidae GENUS: Homo SPECIES: Sapiens
Explain why taxonomic classification may change over time.
As more information is gained about them like their DNA structure.
What is the source of genetic variation?
Mutations in the DNA and sexual reproduction.
What does DNA stand for?
Deoxyribonucleic acid
What is DNA?
A large & complex molecule found in all living cells. It’s job is to carry information between generations.
Where is DNA found?
Two places in eukaryotic cells 1.) In the nucleus - contains most of the genesthat control the cell. 2.) Mitochondria and plastids - contain extranuclear genes that control the function and reproduction of these subcellular components.
What are Chromosomes?
Nuclear DNA and protein
Where is DNA found in eukaryotic cells?
1.) In the nucleus - contains most of the genesthat control the cell. 2.) Mitochondria and plastids - contain extranuclear genes that control the function and reproduction of these subcellular components.
State the function of DNA.
DNA carries inform between generation.
What are the 4 nitrogenous bases in DNA?
A.C.T.G. (Adenine, Cytosine, Thymine, Guanine)
What does RNA stand for?
Ribonucleic acid
What is the nitrogenous base in RNA?
Uracil
How many genes are in a chromosome?
Thousands
How many nucleotides are in a gene?
Hundreds to thousands
What are polypeptide chains?
Proteins
What determines a cells structure?
Polypeptides
What are triplet codes?
3-nucleotide sequences found in genes (64 combinations of AUCG)
Meiosis?
Separates the chromosomes of the parents into two complete sets. (diploid cells split into haploid cells and when male and female haploids join they become zygote cells which are diploids again.
Mitosis?
Somatic cell division; nuclear division in which the duplicated chromosomes separate to form two genetically identical daughter nuclei.
Extranuclear DNA?
control function and reproduction
Gene?
Determine the structure of the polypeptide
Genetic code?
Consists of all possible triplets that can be made by combining the four nucleotides in different ways (64)
Allele?
One form of a particular gene
What is the molecular structure of DNA?
Sugar, Phosphate, and Nitrogenous
Relationship between genes & DNA?
DNA provides the nitrogenous bases that form the triplets of genes.
Relationship between nucleotides & DNA?
DNA is made of subunits of nucleotides.
Relationship between genes & nucleotides?
Genes are made of many 3-nucleotide sequences called triplet codes.
Relationship between genes & proteins?
Genes determine the structure of proteins (polypeptide chains)
Which living things use the genetic code?
All living things use the genetic code
Explain the genetic basis of the differences between species?
Each species has a different amount of DNA in each cell.
Explain the genetic basis of the differences between individuals in the same species?
Each individual within a species gets a slightly different combination of alleles.
Explain the genetic basis of the differences between cell types within a individual?
Not all genes are active all the time in all cells.
How is DNA related to reproduction?
When reproducing organisms have to pass on a copy of their DNA to the offspring.
What is the cumulative effect of mutation over millions of years?
It has brought about the biological diversity that exists on the earth now.
Transmission of traits from one generation to another is known as
Heredity
A biome found along the coast of continent with rainy winters ans long dry summers is known as ____.
Chaparral
Semi conservative
A model describing principle of DNA replication
Mechanism to fix DNA that has been incorrectly replicated?
proofreading, mismatch repair, nucleotide excision repair
One difference between bacterial DNA and Mammalian DNA is that bacterial DNA _____.
Is circular