The Study Of Life Flashcards
What are the characteristics of life
Are composed of cells
Grow and develop
Respond to stimuli
Regulate their metabolic process
Reproduce
Evolve and develop
Have levels of organization
What is the cell theory?
New cells originate only from pre-existing cells
Prokaryotes vs.Eukaryotic cells
Prokaryotes-are unicellular organisms and they no nucleus.
Example: Monerans(bacterias)
Eukaryotic- can be unicellular or multicellular and they have a nucleus.
Examples: Protists, plants and animals.
Explain the term growth
Growth- an increase in cell size, cell number or both
What does the term respond to stimuli mean
Responding means to react to the physical and chemical changes in our internal and external environment.
We detect internal changes through our receptors.
Movement may be created by ?
Cilia
Flagella -enables many organisms to swim eg. spermatozoa
How do organisms regulate their metabolic processes
Through hormones
Example would be the process of homeostasis- maintains a constant internal environment.
Explain a negative feedback regulation
When the body response is to counteract a stimulus that is disrupting homeostasis. The accumulation of an end product of a process slows it down. Examples: the regulation of blood sugar levels and temperature regulation.
Explain what is a positive feedback regulation
When the original stimulus enhances the response an end product speeds up this process.
Example: when a woman goes into labor the contractions of the uterine done to speed up the process of giving birth to a
What are the two ways of reproduction
Asexual reproduction- the production of an offspring without the contribution of genetic material from another individual.
Examples: budding, fragmentation and parthenogenesis.
Sexual reproduction- the production of an offspring by the fusion of gametes. Egg and sperm fuse to form a zygote.
Explain what happens in any two types of asexual reproduction
Parthenogeneses- a female egg develops into a new organism without needing to be fertilized by a sperm cell.
Example: frogs
Fragmentation- a parent breaks into multiple pieces,and each develops into a fully functioning independent individual.
Example: starfish
Explain evolution and adaptation
Evolution- changes in population over time.
Adaptation- make something suitable for a new use or purpose; modify.
Adjusting to new condition whether it be structural,physiological and or behavioral.
How are living things organized?
Starting from the smallest particle that can exist is how we organized.
Atom-molecules-cell-tissue-organs-organ system which gives you a multicellular organism.
Organization in a community
Population - community - ecosystems- biosphere
How does information transfer within an organisms (externally)
Cell to cell chemical signals
Through nerve cells and hormones.
What are the 4 features of natural selection
Variation- within a population, individuals differ from one another, through random mutation
Inheritance-traits are passed on genetically from parent to offspring.
Selection- some organisms reproduce more than others.
Time- variation accumulate over many generations.
