Bio Test #1 Flashcards
things i have studied
Biology
study of life
Biologist
study how living things work, interact with their environments, and change over time
How do we determine if something is living or not?
By the 7 characteristics: organization, homeostasis, metabolism, growth & development, reproduction, response to stimuli, change over time
organization
high degree of order within an organism
cell
basic structure of organization, smallest living thing
atom
smallest unit of matter
Homeostasis
equilibrium, “same stillness; how the body maintains its internal stability even if external conditions are constantly changing
negative feedback mechanism
trying to create a response that is opposite; when the body senses a change it activates a response that negates or reverses the change, Ex. if temperature goes down, the response pushes the temperature up
Receptor
structure that senses change
Control Center
processes the info & makes decision about what response to use
effector
structure that carries out the response and restores homeostasis
Positive Feedback Mechanism
generates a response that reinforces or continues the change; can be harmful or life threatening because of its self-amplifying nature; it brings the organism even further from the equilibrium. Ex: child birth- baby’s head pushes against the cervix triggering contractions, baby pushes even more, contractions get stronger, baby comes out, contractions stop
metabolism
complete set of chemical reactions that occur in living cells, push & fueled through energy
What are the differences between the 2 metabolic reactions: catabolic & anabolic?
catabolic- yield energy by breaking down compounds
Anabolic- use energy to build new compounds
metabolic pathways
series of chemical reactions catalyzed by enzymes
Enzymes
proteins that speed up the rate of the reaction
Metabolic Rate
speed of metabolism, different for each species & it influences how much food an organism is going to require
development
any change in form of function in the life time of an organism
growth
generally a change in size
differentiation
process in which cells that are not specialized (generalists/ stem cells) become specialized & start performing a specific task
reproduction
passing of genes onto offspring
What are the 2 ways to reproduce?
Asexual- uses mitosis, & only 1 organism needed, new organism is identical to parent organism
Sexual- meiosis, 2 organisms are needed for the formation of sex cells called Gametes, new organism is different from both parent organisms
Stimulus
change, can be external (environment) or internal (inside body cell)
What are the 3 main themes of biology?
Diversity & Unity of Life Interdependence of Organisms Evolution of Life
Genetic Code
all living things have DNA
DNA
made of the same molecules in all living things, has the same shape (double helix) in all living things; the foundation of genetic engineering
presence of organelles
not all the same one are present in all cells, but there are some
Carolous Linnaeus
created the binomial system in 1735
Rules of Binomial System
each species has 2 name (genus & species); Genus is always capitalized and species is always lower-cased; names must be in Latin; handwritten names must be underlines; when typed it must be in italics; when wanting to shorten the name after the first full out name, write the 1st initial of the genus, and the whole species name
What is the purpose of classification?
to avoid confusion between scientists all over the world by studying organisms & organizing them we can understand evolutionary relationship
can help us predict physiological responses or genetic characteristics of different species
ecology
science that studies how organisms interact with each other and their environment
species
all organisms that share similar characteristics can interbreed & produce fertile offspring
population
animals of the same species that live in the same area
community
all the different populations living in the same area
biosphere
all areas of air, land & water where life is found
ecosystem
communities & their environment; characterized by energy flows and chemical cycling
climate
general pattern of the weather, main factor that determines where a certain ecosystem will occur
Human Population
the only species that can modify ecosystems for our own purpose, causes them to be the main organisms responsible for destruction or damage of ecosystem; depend on a healthy ecosystem for food, medicines, raw materials
biodiversity
total number of species in an ecosystem, used to gauge the health of an ecosystem
extinction
death of a species or a large group; preserving biosphere helps prevent this; 400 species are affected by this every day
evolution
process by which inherited characteristics within a population change over generations to the point that eventually a new species can emerge
what does evolution explain?
how organisms alive today are related to those in the past, helps us understand mechanisms behind organisms’ look & behavior
Natural Selection
ability of population of organisms to change over time
Why is natural selection important?
It allows survival in an ever changing environment
Evolution by Natural Selection
organisms that exhibit certain favorable traits are more likely to survive & reproduce
What is a product of evolution by natural selection?
adaptations
Adaptations
traits that improve an individuals ability to survive & reproduce in a specific environment
Charles Darwin
person responsible for introducing the concept of evolution by natural selection
Scientific Method
an organized approach to analyze any question about the natural word
What are the 2 main principles that the scientific method is based on?
- all events in the natural world have a natural cause
2. uniformity- the same laws apply in the same way at all times & places
Steps of the Scientific Method
- Observation
- Hypothesis
- Prediction
- Experiment
- Analyze Data & Draw Conclusions
- Communicate to peers
observation
fact that generates a question, “curiosity”
Hypothesis
come up with possible answers
Prediction
propose an outcome for the hypothesis
Experiment
How you decide to test your hypothesis
What are the steps of experiments?
- Set experimental groups
- Set variables
- The amount of repetitions
control group
an experimental group that offers a base line to compare your results
What can control be?
Control can be either the treatment that reproduces what happens “naturally” or the group where the treatment is not applied
independent variable
what is manipulated by the experimenter; should be the only thing that changes among the experimental groups; try to specify a unit if possible
Dependent Variable
what is effected by independent variable; what you measure; always remember to specify unit
controlled variables
all the other variables that affect the dependent variable & that need to be kept the same so that they do not influence the effect of the independent variables
What are ways to have repetitions?
repeat experiment several times or increase the number of trials or both
organization
high degree of order within an organism’s internal & external parts, & in its interactions with living world
unicellular
made up of one cell
multicellular
made up of multiple cell
organ system
groups of specialized parts that carry out a certain function in the organism, made up of organs
organs
structures that carry out specialized jobs within an organ system, made up of tissues
tissues
groups of cells that have similar abilities and that allow organs to function
what must cells have?
cells must be covered by a membrane, contain all genetic info needed for replication, & to carry out their functions
organelles
tiny structures that carry out functions needed for the cell to stay alive
biological molecules
the chemical compounds that provide physical structure & that bring about movement, energy use, & other cellular functions, made up of atoms
Why do living things grow?
resulting from the division & enlargement of cells
cell division
formation of 2 new cells from an existing cell
Why is reproduction important?
it is essential to continuate the species
gene
a short segment of DNA that contains the instructions for a single trait of an organism
domains
major subdivision of all organisms