Unit 1: Life, Cells, and Microscopy Flashcards
atom
The fundamental building block of all matter, living or not.
biosphere
The sum of all ecosystems: every region of Earth where organisms live, extending across the lithosphere, hydrosphere, and atmosphere.
cell
The smallest unit of life. This is where the magic happens!
community
All populations of all species and their interactions within a habitat.
ecosystem
A community interacting with its physical, abiotic environment through the transfer of energy and materials.
emergent property
A characteristic of a system that does not appear in any of the system’s component parts. (e.g. “roundness”)
molecule
An association of two or more atoms, joined in a chemical bond.
organ
A group of tissues that work together to perform a collective task.
organ system
A group of organs that work together to perform a collective task.
organism
Individual that consists of one or more cells.
population
Group of interbreeding individuals of the same species that live in a given area.
tissue
In multicelled organisms, specialized cells organized in a pattern that allows them to perform a collective function.
When do the unique properties of life emerge?
They emerge as certain kinds of molecules become organized into cells.
When do emergent properties occur?
They occur at each successive level of life’s organization.
What do the higher levels of life’s organization include?
They include multicelled organisms, populations, communities, ecosystems, biomes, and the biosphere.
What are the “molecules of life”?
Lipids, proteins, DNA, RNA, and complex carbohydrates.
How do cells survive and replicate themselves?
They do this by using energy, raw materials, and information in their DNA.
consumer
Organisms that get energy and nutrients by feeding on tissues, wastes, or remains of other organisms.
development
Moving from a single cell to a multicelled adult (if applicable)
DNA
Deoxyribonucleic acid
energy
The capacity to do work.
growth
An increase in the number, size and volume of cells.
homeostasis
The set of processes by which an organism keeps its internal conditions within tolerable ranges.
inheritance
Transmission of DNA to offspring.
nutrient
A substance that an organism needs for growth and survival, but which it cannot make for itself.
photosynthesis
The process by which producers use light energy to make sugars from carbon dioxide and water.
producer
And organism that makes its own food using energy and simple raw materials from the environment.
reproduction
The processes by which individuals produce offspring.
What do living things have in common? (unity)
They require energy and nutrients, they sense and respond to change, they consist of one or more cells, and they use DNA.
archaeon (archaea)
A single-celled prokaryote that is more closely related to eukaryotes than to bacteria.
bacterium (bacteria)
A member of the most well-known and diverse single-celled prokaryotes (lacking a nucleus).
biodiversity
The scope of variation among living organisms.
eukaryote
An organism who cells characteristically have a nucleus.
fungus
A single- or multicelled eukaryotic consumer that digests material outside its body, then absorbs released nutrients.
nucleus
The double-membraned sac that encloses a cell’s DNA.
protist
A member of a diverse group of simple eukaryotes.
How do organisms differ from one another?
Complexity of the cell (prokaryotic vs. eukaryote)
Organization (uni- vs multi-cellular)
Mode of nutrition (consumers vs. producers)
species
A unique type of organism; however, it’s important to remember that “species” is a convenient but artificial construct of the human mind.
What info does DNA carry?
It carries hereditary information.
What does the info inside DNA guide?
It guides growth, development, functioning, and reproduction.
What do you call the first cell formed in humans by the sperm fertilizing an egg?
A zygote
What do we call organisms with no nucleus and no organelles?
Prokaryotes
What are the two kinds of prokaryotes?
Bacteria and archaea
What do we call organisms with a nucleus and organelles?
Eukaryotes
What kind of organisms are unicellular and/or form colonies and filaments?
Protists (i.e. kelp)
What does “true” tissue mean when defining multicellular organisms?
They have actual specialization and interact to fulfill collective tasks
How do fungi feed?
By externally digesting their food and then absorbing it.
What makes up the outer barrier of a cell?
Lipids, specifically phospholipids
What is the evolutionary advantage to being multicellular?
Specialization and division of labour; in unicellular organisms, the single cell must do ALL the work.
biome
A larger region containing ecosystems with similar climate, plants, and animal populations.
Who was the first person to describe a cell?
Robert Hooke
When did Hooke live?
1635-1703
What material was Hooke working with?
Cork, so all the cells he observed were dead
Who was the first to describe living cells and when?
Anton van Leeuwenhoek in the 1600s
What are the four points of Cell Theory?
(Everything Basic Before DNA)
- All living things are made of cells.
- The cell is the basic unit of structure and function.
- All cells come from preexisting cells.
- Cells contain genetic information.
What is the mystery of life?
That, as far as we can tell, all cells come from preexisting cells…so where did the first one come from?
What do all cells have?
- A cell membrane
- Cytoplasm
- DNA (at least at the start of life)
What is cytoplasm?
Basically, whatever is inside the cell that isn’t the nucleus.
What is metabolism?
All the chemical reactions that happen in a cell to keep it functioning?
How is metabolism related to living things?
All living things need nutrients and energy to do metabolism.
The cell is the basic unit of “structure” and “function”.
What does “structure” mean?
It is the building blocks of life.
The cell is the basic unit of “structure” and “function”.
What does “function” mean?
It is the smallest unit that performs the functions of life, i.e. does metabolism, like enzyme production.
What two things does a microscope provide?
Magnification and resolution.
What is magnification?
Enlarging small objects by a factor of how many times the object gets larger.
What is resolution or resolving power?
The ability to distinguish between two objects.
What are the three different kinds of microscopes?
Compound light microscope, scanning electron microscope, and transmission electron microscope.
How does a compound light microscope work?
It uses visible light and lenses to illuminate its subject.
What are the two lenses called in a compound light microscope?
Ocular and objective.
Which lens is closest to the specimen in a compound light microscope?
Objective
Which lens do you look through in a compound light microscope?
Ocular
What is the smallest thing a compound light microscope can see?
Certain kinds of bacteria.
What does a scanning electron microscope show?
Surface details of cells and structures.
What does a transmission electron microscope show?
Detailed images of internal structures.
What do you call the outer layer that separates a cell’s contents from its environment?
The plasma membrane
What do you carry a microscope by?
The arm
What do you call that part of microscope that you look through?
The eyepiece
What do you call that part of microscope that you rotate to look at things?
The revolving nosepiece.
What do you call that part of microscope that holds a slide down?
The stage clip
What do you call that part of microscope that is the smallest magnification?
Low-power objective
What do you call that part of microscope that is the largest magnification?
High-power objective
What do you call that part of microscope that you set a slide on?
The stage
What do you call that part of microscope that controls how much light goes through?
The diaphragm
What do you call that part of microscope that provides light?
The substage lamp
What do you call that part of microscope that you use FIRST for focusing?
The coarse adjustment
What do you call that part of microscope that you use SECOND for focusing?
The find adjustment.
