Module 2A - What is life? Flashcards
(22 cards)
Abiotic factors
non-living components of the environment (water, fire, gas)
- Influence survival of living organisms
What is the 7 characteristics of life?
- Living organisms consists of one or more cells
- Life requires a constant input of energy and raw material
- Life conducts metabolism (all chemical reactions occur within an organism)
- Organisms grow and develop (increase size and change over time)
- Living organisms exhibit homeostasis (regulate internal environment)
- Makes short term responses to stimuli in surroundings
- life reproduces itself
4 factors of cells:
- are the basic structural and functional (physiological) units of living organisms
- contains DNA, cell membranes and ribosomes
- are only produced from division of pre-existing cells
- have basically the same chemical composition
What is the unity of life?
shares a common ancestor
what is the tree of life?
evolutionary relationships of organisms
polymorphs
morphs of a single species
Can change colours
What are the 4 elements that comprise an organism?
- Oxygen
- Hydrogen (mix together with oxygen to make water)
- Carbon (major building block of all living matter)
- Nitrogen (vital element in all proteins)
Living organisms have many types of biomolecules that include:
- carbohydrates (CHO)
- lipids (CHO)
- proteins (CHONS)
- nucleic acids (CHONP)
What is the hierarchy of life?
levels of biological organization
All cells can be divided based on their cellular structure:
a) unicellular vs multicellular
b) prokaryote vs eukaryote
Autotroph
synthesize their own food (self feeders) from inorganic material (contains either carbon or hydrogen) to make organic materials
Heterotroph
require preformed organic molecules
- use energy in organic matter (contains carbon and hydrogen) eaten from other organisms
Two types of autotrophs:
- photoautotroph - use light energy and inorganic materials (water and carbon dioxide)
- chemoautotrophs - use inorganic compounds (H gas, S, NH3) as energy sources and don’t need light
Two types of heterotrophs
- photoheterotrophs - use light energy to generate ATP, but need to take organic compounds from their environment (doesn’t do photosynthesis)
- chemoheterotrophs - must obtain organic compounds for both energy and as a carbon source (most heterotrophs)
What is a mixotroph?
swaps from several phases going from autotropy to heterotrophy
- uses photosynthesis
- when light isn’t available they switch to chemoheterotroph
Response to stimuli: how do cichlid fish behave?
- the macho (dominant) and whimpy (subdominant) are always together
- when macho dies whimpy fights other whimpy
- combat causes growth, might out compete a macho and become one
- can turn back into a whimpy
4 types of asexual reproduction:
- Fission
- Budding
- Fragmentation and regeneration
- Parthenogenesis (animals)
Fission
- binary fission: individual separates into 2 individuals of equal size (simplest)
- multiple fission: one individual separates into multiple of equal size
Budding
new individual arises from an outgrowth of another
- “daughter” is of a different size
Fragmentation and regeneration
parent breaks off into pieces, each piece gives rise to new individual
Parthenogenesis (animals)
development of an individual from an unfertilized egg (female lays eggs)
Ex. honey bees
Honey bees (colonial bees) in reproduction
- Diploid queen mates with a male haploid drone for the queen to lay eggs
- female diploid workers are produced
- only haploid male drones are produced when the queen runs out of sperm but continues to lay eggs (parthenogenesis)
