Chapter 1: Evolution, the Themes of Biology, and Scientific Inquiry Flashcards
Characteristics of life:
- composed of cells.
- organized: uses smaller structures to make bigger structures
- respond to the change in environment
- Maintain homeostasis
- able to reproduce
- energy acquisition from environment
- contain genetic info (DNA)
- Ability to evolve/adapt
What is mass and weight and what is the difference between?
Mass is the amount of matter in an object and it is constant regardless of gravitational influences. (Measured in Kilograms, and grams)
weight is how much force gravity exerts on that object (varies with location) measured in pounds and newtons
What criteria must be met in order for an organism or creature to be considered alive:
Must exhibit all 8 properties of life.
Creatures who exhibit potential for life are not considered alive
Define the following terms:
Evolution:
DNA:
- changes to the DNA of a population over long periods of time.
- genetic material of life found in all living organisms.
Are viruses considered alive, why or why not?
No, because they don’t exhibit all the properties of life
List life’s organizational Hierarchy from smallest to largest:
- Atom
- Molecules
- Organelles
- Cells
- Tissues
- Organ
- Organ system
- Multicellular organism
9.Population - Community
- Ecosystem
- Biosphere
Define the following parts of the organizational hierarchy of life:
1. Atom:
2. Molecules:
3. Organelles:
4. Cells:
5. Tissues:
6. Organs:
- anything that takes up space and has mass
- a combination of atoms (water= 2 hydrogen atoms+ oxygen atom)
- specialized structures within cells (not considered alive)
- organelles coming together (unicellular)
- cells that are similar in structure and work together to perform a particular function
- a group of tissues performing a specific function.
Define the following parts of the organizational hierarchy of life:
7. Organ system
8. Multicellular organism
9. Population
10. Community
11. Ecosystem
12. Biosphere
- a group of organs working together to perform a specific function.
- an individual form of life composed of many cells
- Organisms of the same species living in the same area.
- multiple populations of different species living in the same area. (only living)
- living and non- living surroundings in the area.( mountains, etc.
- all of the different ecosystems on earth that support life
What is the biological term for living and nonliving things:
Biotic= living
Abiotic= non- living
Q: What is an atom?
A: An atom is the smallest unit of an element that retains all of its properties and abilities.
Q: What is an element?
A: An element is a substance made up of only one type of atom.
Q: What is a molecule?
A: A molecule is made up of two or more atoms bonded together. The atoms can be the same (e.g., O₂) or different (e.g., H₂O).
Q: What is a compound?
A: A compound is a molecule made up of two or more different elements bonded together (e.g., H₂O, NaCl).
Q: Can a molecule be made up of the same element?
A: Yes, a molecule can be made up of the same element, like O₂ (oxygen molecule).
Q: What is the difference between a molecule and a compound?
A: A molecule can be made of the same or different elements, while a compound is specifically made of different elements.
Q: Are all compounds molecules?
A: Yes, all compounds are molecules, but not all molecules are compounds. Compounds must involve different elements, while molecules can consist of the same element.
What is an emergent property and when does it happen?
properties that arise upon combining smaller parts together. Only when smaller parts are combined does the emergent property arise.
What happens at each level of the hierarchy?
an emergent property arises
Explain the process of emergent properties?
The whole is greater than the sum of its parts
Define Adaptation:
process that enables organisms to improve survival and reproduction chances in their environments
What is Fitness in the biological sense:
an organism’s ability to survive and reproduce
What is natural selection/ survival of the fittest?
causes adaptation. is when the natural environment selects for organisms in a population that are more fit.
What are the two requirements for natural selection:
- genetic diversity within a population
- selective pressure for heritable traits affecting fitness.
What is one way in which evolution can occur?
through natural selection
What is evolution?
is the process in which a population undergoes BIG changes over long periods of times leading to the development of a new species.
What is taxonomy:
branch of science that deals with classifying, identifying, and naming organisms.
What are the 8 categories used to classify all life?
Dear King Philip Came Over For Great Soup
D- Domain
K- kingdom
P- phylum
C- class
O- order
F- family
G- genus
S- species
What is a domain and what are the 3 domains of life?
is the most inclusive category used to classify life.
1. Bacteria.
2. Archaea.
3. Eukarya
What is the defining feature of the bacteria and archea domain of life and what does it consist of?
they lacks a nucleus. consists of prokaryotic cells
what is a prokroyote?
single-cell organism whose cell lacks a nucleus and other membrane-bound organelles.
What is the defining feature of the eukarya domain of life and what do it consist of?
consist of euokyrtic cells, and contain a nucleus
How did the three domains of life emerge?
through evolution and natural selection,
State whether the following is uni or multicellualar:
1. Prokaryote:
2. Eukaryotes:
- unicellular organisms
- contain some unicellular organisms and all multicellular organisms.
What are kingdoms of the eukarya domain and do they contain multicellular or unicellular organisms.
- Kingdom animalia- multicellular
ex- humans, tigers, etc - Kindgom Plantae- multicellular animals
ex- flowers, plants, etc. - kingdom fungi- mostly multicellular
ex- mushrooms - Protista- uni/multicellular
What are protists?
diverse group of eukaryotic microorganisms that do not fit neatly into the categories of plants, animals, or fungi
What are the 3 classes of organisms based on energy acquisition?
- Producer (autotrophs)- make their own food
- Consumer- (heterotroph)- eat other organisms.
- Decomposers- decomposing other organisms (waste, dead)
Where does most of the energy utilized by life come from?
the sun
What happens during every energy transfer, briefly describe the process?
with every energy transfer, part of that energy is lost in the form of heat.
EX- produces take energy from the sun and in that process heat is lost, and then consumers eat producers, and energy is transferred therefore resulting in another heat transfer, and the same happens when energy transfers to decomposers.
Q: What is the primary source of energy for most organisms on Earth?
A: The sun.
Q: How do plants capture energy from the sun?
A: Plants absorb light energy through their chlorophyll.
Q: What is the process by which plants convert light energy into chemical energy?
A: Photosynthesis.
Q: What are the main products involved in photosynthesis?
A: Carbon dioxide (CO₂), water (H₂O), and light energy are used to produce glucose (C₆H₁₂O₆) and oxygen (O₂).
Q: Where do plants get carbon dioxide and water from for photosynthesis?
A: CO₂ comes from the environment (absorbed through the stomata), and H₂O comes from the soil (absorbed through the roots)
Q: What happens to the glucose produced by plants in photosynthesis?
A: The glucose is used by the plant in cellular respiration to produce ATP, which powers its cellular functions.
Q: Do animals also perform cellular respiration? If so, why?
A: Yes, animals perform cellular respiration to break down glucose into ATP, which is used to power their cellular functions (such as movement, digestion, etc.).
Q: How do animals obtain energy from plants?
A: Animals consume plants, and the sugars in the plants are broken down in the animal’s cells during cellular respiration to produce ATP.
Q: How is energy transferred from plants to animals?
A: Energy is transferred when animals consume plants (producers) and break down the stored sugars into ATP.
Q: What is the byproduct of cellular respiration in plants and animals?
A: The byproducts are carbon dioxide (CO₂) and water (H₂O), which are released into the environment.
Define the scientific method, what does it start with?
are procedures used to answer questions, test ideas, and gain scientific knowledge
it starts with an observation/ question
List the steps of the scientific method?
- make an observation
- ask a question
- formulate a hypothesis and make a prediction
- Design/ conduct an experiment
- collect/ interpret data
- Draw conclusions (accept or reject initial hypothesis)
- Peer review and publish
Define the following terms:
1. Prediction:
2. Hypothesis:
3. Theory:
- expected outcome of an event
only answers the “what will happen?
can either be correct or incorrect. - a proposed and testable explanation for an observation.
Answers what will happen and why will it happen. good hypothesis= includes a prediction. - testable/ broad hypothesis of many observations, supported by a large body of evidence
Can hypothesis and theories ever be proven to be a 100%, correct?
they can never be proven to be correct, only flasfied.
They are generally accepted based on current evidence, but we can’t say that they are 100% correct, we can only say they haven’t been proven wrong yet and remains to be open for revision.
What is the principle of Falsifiability?
for a hypothesis/ theory to be scientific, it must be capable of being tested and potentially proven wrong.
What are the three basic theories of biology?
- Cell theory: all organisms are made up of cells, and all cells come from prexisting cells.
- Hemostasis: all organisms maintain an internal stable and consistent environment
- Evolution: all living organisms evolved from a single common ancestor.
define the following terms:
1. experimental design:
2. variable:
- a scientific investigation/ procedure designed to test the validity of a hypothesis/ theory.
- two main types. refers to the changeable element of the experiment
. What are independent and dependent variables?
independent variables (x axis): controlled by the researcher
ex- age, time, amount, etc
dependent variables (y axis): measured by the researcher
ex- growth of a plant
What do well designed experiments contain?
control groups which help prevent false negatives/ positives.
Define the following:
1.False negative:
2. False positive:
- outcomes that falsely indicate the presence of a result
- outcomes that falsely indicate the absence of a result
What are the two types of controls used in an experiment?
Positive- a control group where a response is expected (makes sure everything works as it should be)
negative- a control group where no response is expected (makes sure nothing goes wrong by accident
What is the importance of the positive and negative control group?
they are important in validating your results and ensuring your experiment is functioning as expected.
What are the five unifying themes of biology:
- evolution.
- information.
- structure and function
- energy/matter
- interactions
What is the genus and the species name for humans?
the genus of the human species is ‘homo’ and the species name is “homo sapians” or us humans. The genus includes other extinct but closely related species.
Must the steps of the scientific method be followed in any particular order?
no, different investigations will move through the steps in different ways
why is it helpful to form a hypothesis?
narrows your investigation to a single idea to be tested
What is a hypothesis?
a rationale for a set of observations that leads to predications that can be tested and experimented.
what is a prediction?
the results we should expect if our hypothesis is true. Often takes a if-then form.
what is a controlled experiment?
an experiment in which an experiment group is compared with a control group that varies only in the factor being tested.
what is a placebo in the context of a clinical trial?
a treatment that doesn’t contain the substance being tested. a fake treatment that looks like an active drug but doesn’t contain any active ingredients.
what is a prospective and a retrospective study?
- prospective= a study where researchers follow participants over time to observe future outcomes.
- retrospective= a study where researchers look at past data or events and analyze them to draw conclusions.
describe the process of science?
it is nonlinear, repetitive, and collaborative.
how is a hypothesis shaped?
thru exploration and discovery such as reading literature, making observations, and can also be shaped thru interactions with the SC and society
why is hypothesis testing at the center of the process of science?
because a core component of science is testable explanations of nature.
What were the main points presented by Darwin in his book ‘On the Orgins of Species”?
- this idea of common ancestory. species living today rose from a sucession of ancestors that was different from them (descent with modifications”)
- the mechanism thru which evolution happened is called natural selection.
what is the difference between artificial and natural selection?
artificial is driven by human choice while natural selection is driven by Enviromental factors
what is DNA, what is it made up of? what are genes, what are they used for?
DNA is a double helix made up of 4 kinds of building blocks called nucleotides. (A,T,C,G)
DNA contains all of the sequences that are necessary for survival, of those sequences there are some called genes which are specifically responsible for making proteins.
What is gene expression?
Gene expression is the process by which information from a gene (DNA) is used to make a protein that performs a specific function in the body.
What happens during transcription?
During transcription, the DNA’s information for making a protein is copied into mRNA, which is like a written recipe for the protein.
What is the first step in gene expression?
he first step is transcription, where the DNA recipe is copied into mRNA (messenger RNA).
Where does mRNA go after transcription?
After transcription, the mRNA leaves the nucleus and travels to the ribosome in the cytoplasm.
What happens at the ribosome during gene expression?
At the ribosome, the mRNA is “read,” and the ribosome assembles amino acids into a protein based on the mRNA’s instructions.
What is the second step in gene expression?
The second step is translation, where the mRNA’s code is used to build a protein.
What are proteins made of?
Proteins are made of amino acids, which are linked together in a specific order based on the mRNA instructions.
Why is gene expression important?
Gene expression is crucial because it allows our cells to make proteins, which carry out essential functions in the body, like building muscles or fighting infections.
