Chapter 1 - Characteristics of Living Flashcards
What are the 8 Properties of Life?
-order
-sensitivity or response to the environment
-reproduction
-adaption
-growth/development
-regulation/homeostasis
-evolution
-energy processing
What is the ORDER property?
organisms are highly organized have a coordinated structure
-consist of 1 or more cells
What is the SENSTIVITY/RESPONSE TO STIMULI property?
organisms respond to diverse stimuli
-EX) plants bend to source of light, climb up walls, respond to touch
-EX) bacteria move to food and away from chemicals
What is the difference b/w a positive response and negative response?
Positive - moving toward stimuli (bacteria - food)
Negative - moving away from stimuli (bacteria - chemicals)
What is the Reproduction property?
Single-celled organisms duplicate their DNA and divide it = as cells prepare to divide to two cells, same DNA; OR conjugation (exchanging cells)
Multicellular cells typically produce specialized cells for reproduction (gametes, oocyte, sperm cells) which creates new individual w/ fertilization
What is Heredity?
Genes containing DNA are passed to offspring, ensures that offspring will belong to same species and will have similar characteristics to their parents (like size and shape)
What is DNA?
Deoxyribonucleic Acid - genetic material, code of protein information (amino acid)
What is Spontaneous Generation?
People used to think that living things came from nonliving things - mice came from chess, maggots from meat, etc.
Explain Redi’s Experiment:
3 containers - one no lid, one lid, one with mesh so air can go through but nothing else. Each container had meat inside.
No Lid = flies attracted and maggots on meat
Lid = nothing!
Mesh = flies and maggots on top of mesh
Conclusion : maggots came from the flies that were attracted to the meat, not the meat itself
BIG IDEA = Spontaneous Generation not true, living things come from other living things!
Explain Pasteur’s Experiment:
beaker with medium of broth for living things, swan neck connected that was blocked off - only air inside
broth boiled to kill all living things - blank slate
when swan neck cut, air was allowed in and living things were again found in the medium.
What are the main differences between adaptation and reponse?
adaptation - long time, changes DNA
response - detectable change, instant
What is the Adaptation property?
all living things exhibit a “fit” to their environment
-consequence of evolution by natural selection
-operates in every lineage of reproducing organisms
-enhances reproduction potential, survive to reproduce
-EX) stickbug looks like stick to camoflage
What is the Growth/Development property?
Growth - become larger
Development - change, become more complex
-result of genes providing specific instructions that will direct cellular growth/development
-ensures that a species’ young grow up to exhibit similar characteristics as its parents
-EX) Living things can repair damaged parts
What is the Regulation/Homeostasis property?
organisms require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses
Homeostasis : relatively stable internal environment required to maintain life (nutrient transport, blood flow)
-Cells require appropriate conditions (proper temp, pH, concentration of chemicals) to function properly; but conditions may change (higher body temp = proteins not working)
-Organisms can maintain homeostatic internal conditions almost constantly despite environmental changes
What is the Energy Processing property?
all organisms use a source of energy for their metabolic activities (energy from sun, from food)
-occurs in all living things at cellular level
-EX) photosynthesis - energy from sun –> chemical energy
-EX) cellular respiration - chemical energy from molecules as food
What is the Evolution property?
Diversity of life comes from mutations (random changes in hereditary material over time)
-mutations allow the possibility for organisms to adapt to the changing environment
-an organism that evolves characteristics fit for the environment has greater reproductive success
What is an atom?
The smallest unit of matter
-retains properties of an element, consists of a nucleus surrounded by electrons, incapable of division
What is a molecule?
Formed by atoms, chemical structure of at least two atoms chemically bonded
-EX) H2O, H2, CO2, O2
What is a macromolecule?
large molecules, typically formed by polymerization (combining monomers)
-EX) DNA
What is an organelle?
Aggregates of macromolecules surrounded by membranes, small structures, exist within cells, has function
-EX) mitochondria, chloroplasts
What is a cell?
Basic building block of all living things
-The smallest fundamental unit of structure and function
-classified as prokaryotes and eukaryotes
What are tissues?
combined cells, groups of similar cells that carry out similar/related functions
What are organs?
collections of tissues grouped together performing a common function
What are organ systems?
made of functionally related organs
What are organisms?
individual living entities
What is a population?
all individuals of a species living in a specific area
What is a community?
sum of populations inhabiting an area
What is an ecosystem?
all living and nonliving parts of the environment
What is a biosphere?
collection of all ecosystems, zones of life
What are prokaryotes?
single-celled without/before nucleus, simple, less organelles, asexual reproduction
EX) bacteria
What are eukaryotes?
have more membrane-bound organisms and nucleus, more complex, sexual reproduction, better for evolution
-EX) plants, humans, animals
What does a cell require?
DNA
Cell Membrane
Cytoplasm - gel like water with proteins/chemicals
Ribosome to synthesize protein
What are the 3 ancestors?
Eukaryotes
Archea
Bacteria
What is the nucleus?
a specific area for genetic material (DNA)
Is a Virus living?
No, there are no cells and it can’t reproduce without a host
What are the two cycles of viruses?
Lysogenic - inactive form
lytic - active form
What is more complex and organized, a nucleus or nucleoid?
Nucleus
What are compounds?
at 2 elements joined together - CO2, H2O
What are phylogenic trees?
summarizes the evolution of various life forms on Earth
-diagram of evolutionary relationships among species based on similarity/differences in genetic, and physical traits, both
-internal nodes = ancestors, points where an ancestor diverged to form 2 new species
-length of each branch = time elapsed since split
