Chapter 1 Flashcards
First property of life: cells and organization
- cells are the smallest unit of life
- living things are highly organized
- most things in life are unicellular like bacteria and Archeae but plenty are mutlicellular
- we all have at least one cell
Second property of life: energy use and metabolism
- chemical reactions –> metabolism
- everyone alive requires energy and a regular input of it
- if you run out of energy you wont survive
- you can acquire energy from food, if you go long enough without food you die
- chemical reactions go on within the body of an organism and is collectively our metabolism
- maintenance of organisms requires energy
- all living organism acquire energy to maintain internal order
- cells carry out a variety of chemical reactions that are responsible for the breakdown of nutrients
-metabolism- breaking things down (food we eat) to use to build things up
metabolism
chemical reactions breaking things down (food we eat) to use to build things up
-chemical reactions involved with the break down and synthesis of cellular molecules
Third property of life: response to the environment
- to survive organisms react to the environment
- example: phototropism- plants bending toward the light
- able to have input of information from the environment and process it
- organisms vary on how to process the information but we all connect to some extent
Fourth property of life: regulation and homeostasis
- maintain constant internal state
- we all work to maintain homeostatic imbalance- an internal condition we prefer
- we all work to maintain a set point of 98.6
- we all try to maintain some type of homeostasis- chemical imbalance like alcohol, body works to remove it
- bacteria works for this too chemical or pH balance
Fifth property of life: growth and development
- growth- biomass, getting bigger
- development- life stages, changing physiologically your body (from birth to now)
- first born 3rd or more of the body was the head and now developmentally changes gives adult body
Sixth property of life: reproduction
- with DNA as the blueprint
- living things give rise to more living things- this is done by passing DNA from parent to offspring
- DNA is information holding molecule to pass traits from parents to offspring
Seveth property of life: biological evolution
- traits promote survival of the individual and offspring
- evolution- change in genes over time
- looking at a population and how the principles of it change over time
Cells
- cells are the most basic level of life
- the lowest level capable of performing all the activates of life
- all organisms are composed of cells
- all living things consist of cells and cells come from pre-exisiting cells
- simplest unit
Cell theory
- foundation of biology
- every organism has been made up of one or more cells
1. All organisms are composed of cells
2. cells are the smallest units of life
3. new cells come from pre-existing cells via cell divisions
Genes and their expression
- genome- collection of genes that make you up
- genomics- analyzing and comparing DNA whether looking at different people or different species
- genome is a set of directions for the proteome
- proteome- is proteins that are made based on directions in the genome
- they determine each other
- things doing all the work in our body and things that make you, you are due to proteins
- DNA is important and necessary but they are not the ones actually doing stuff, those are the proteins
- central dogma of biology
Central dogma of biology
- start with a bunch of information in our DNA sequence and that is transcribed to a strand called mRNA which takes information out to the cell and uses it to make some more protein
- this process from DNA to RNA to protein is how things happen in any cells body
Evolution- The unifying theory
- change in genes over time
- looking at a population and how the principles of it change over time
- the unifying theory?
Taxonomy
- how life is classified
- grouping of species based on common ancestry
- usually in 3 domains of life
- diversity of life and how we organize everyone on this evolutionary tree
- bacteria and archaea- signle celled oranisms, smaller and more simple in construction, prokaryotic but both very different genetically and biochemically
- eukarya is multicellular and has a nucleus and breaks into 4 kingdoms
1. protist 2. plants 3. fungi 4. animals - bacteria- unicellular, single celled organism, prokaryotes with many diverse environments
- archeae- unicellular, prokaryotic
- different ways to construct the cell wall and membrane than bacteria
- live in extreme environments
prokaryotic
now nucleus or membrane bound organelles, small, many diverse environments
eukaryotic
-DNA is stored in the nucleus, 4 kingdoms, both unicellular or multicellular
organism
-applied to all living things, maintain an internal order that is separated from the environment
metabolism
chemical reactions involved with the breakdown and synthesis of cellular molecules
homeostasis
living cells and organism regulate their cells and bodies to maintain relatively stable internal conditions
growth
produces more or larger cells
development
is a series of changes in the state of a cell, tissue, organ or organisms, eventually resulting in organism with a define set of characteristics
mutation
- how we get new genetic variation to exist
- parents passing traits to offspring and sometimes mutations over time lead to individuals over time lead to individuals having different versions of traits
- the environment changed from forest to grass so the traits varied
- they got bigger to see over grass toes reduced, teeth got bigger
- example: horses used to look like deers and were forest dwelling
- new species arise from an accumulation of mutations (common, rare adaptive mutations is a rare material for natural selection in evolution)
natural selection
traits that are favorable in an environmental condition, then these traits are more likely to be prevalent in the future
Domain: Archaea
unicellular prokaryotes that often live in extreme environments, such as hot springs
- different ways to construct cell wall and cell membrane
- mostly live in an extreme environment
reproduction
generate offspring
genes
segments of DNA, govern the characteristics, or traits of organisms
DNA
provides a blueprint of the organization, development and function of living things
protein
composed of one or more polypeptides
polypeptide
most genes are transcribed into type of RNA molecule called mRNA which is translated into a polypeptide with a specific amino acid sequence
tissue
in the case of multicellular organisms, such as plants and animals, many cells of the same type associate with each other to form tissues
organ
composed of two or more types of tissue
population
a group of organisms of the same species that occupy the same environment
community
a biological community is an assemblage of populations of different species
the types of species found in a community are determined by the environment and by the interactions of species with each other
ecosystem
formed by interactions of a community of organisms with their physical environment
biosphere
- all of the places on the Earth where living organisms exists
- life is found in the air, in bodies of water and on land in soil
Eukarya
- unicellular and multicellular organisms having cells with internal compartments that serve various functions
- 4 kingdoms (protists, plants, fungi and animals)
- all have a nucleus
binomial nomenclature
- each species has a unique scientific name
- genus is capitalized and specific epithet is not capitalized
- both names are italicized
observation
observe something in the natural world, you can see something happening and you want to be able to figure out the cause of it
hypothesis
a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation
hypothesis testing
- observations- you observe something in the natural would, you want to figure out the cause of it
- formulate testable hypothesis- then come up with a causable explanation for these observations
- experiments (control & experimental groups) (vary by a single variable)
- data analysis- statistics to analyze all the information gathered, see if control and experimental are actually different
- Hypothesis (tentatively) accepted or rejected
control sample
don’t change anything
experimental sample
change some variable and compare it with the control group
scientific theory
- nothing is “proven”
- everything subject to modification based on best evidence available
- all claims/hypothesis must be falsifiable
- theory- generally set of principles supported by evidence
- theories generally not is dispute in the scientific community
- though some portions of them may be
- more valuable than a fact because theories have explanatory power
Biology is the study of life
- biology is the study of living things and the study of life
- tree frogs have ameba and sickle cell ameba
- trees and plants all of which have very different properties but all fall under the same category of life
- principles fall under the category of life
12 Principles of Biology
- cells and organization
- energy use and metabolism
- response to the environment
- regulation and homeostasis
- growth and development
- Reproduction
- biological evolution
- Inheritance
- structure determines function
- Emergent properties
- biology is experimental
- biology affect society in many important ways
hierarchical organization of life
- atoms
- molecules and macromolecules
- cells
- tissues
- organs
- organism
- population
- community
- ecosystem
- biosphere
Unity and Diversity of life
Unity- common characteristics
- evolutionary history
- interrelatedness of organisms
- life is organized in 3 different domains
- Diversity- in form
- what an organism looks like, function and what they are doing in the world
- what you look liked and how you behave varies
Two Mechanisms of Evolutionary Change: 1. Vertical Descent with mutation
- Progressive changes in a lineage
- from small deer like to a big animal
- sharing genes or passing genes is through reproduction
- new species evolve from existing species by accumulation of mutations
- new species come from mutations
- natural selection takes advantage of beneficial mutations
- NS traits that are favorable in environmental conditions, then these are the traits that are more likely to be prevalent in the future
- passing genetic information from parent to offspring
- through mutation different individuals have different versions of these traits
how do you get new species?
through accumulation of mutations (common, rare adaptive mutations is a rare material for natural selection in evolution
Two Mechanisms of Evolutionary Change: 2. Horizontal Gene Transfer
- genetic exchange between different species
- example: genes that confer antibiotic resistance are sometimes transferred between different bacterial species
- sharing genetic information with organisms that already exist
- example: bacteria, not making a new individual you share genes with someone who already exist, bacteria shares genes across species within a species
- exampleL readily certain bacteria share genes that give certain antibiotics resistance, any new antibiotic, you can make predictions on how long it’ll be useful for depending on how widely used and how long it is available
Domain Bacteria
- mostly unicellular prokaryotes that inhabit many diverse environments on Earth
- single celled organisms, prokaryotes with many diverse environments
- no nucleus or any membrane bound organelles
Domain: Eukarya
unicellular and multicellular organisms having cells with internal compartments that serve various functions
- 4 kingdoms
- protists- single celled
- plants
- fungi
- animals
- all have a nucleus
classification of life
domain kingdom phylum class order family genus species (Do Kids Play Catch On the Farmer's Grass?)
genome
- we all have it, t is the collection of all of our genes that make up up
- genomics- techniques to analyze/compare DNA
- genome is really a set of direction for the proteome
proteome
- is proteins that are made based on directions in the genome
- things doing all the work in our body and things that make us, us is due to proteins
- DNA is important and necessary but they are not ones actually doing stuff, proteins are
- proteomics- techniques to analyze/ compare proteins
biology as a scientific discipline
- science- is both a body of knowledge and a method to gain that knowledge
- constantly challenging itself, evolving
proving a theory
- nothing is proven
- everything subject to modification based on best evidence available
- all claims/hypotheses must be falsifiable
science is collaborative!
- Within a lab, students, postdocs, technicians, and PI work together
- Different labs often collaborate
- At meetings, scientists discuss new data – and debate!
- You can discuss science without having “all the answers”
- Science is a never-ending series of questions
- Publication is based on peer-review
