bio exam 1

Science

process used to understand the natural world through observations, explanations, testing, and evidence.

-Science = process, not just facts.

4 Key Characteristics of Science

1. It is a process

2. Provides explanations and mechanisms

3. Is self-correcting

4. Makes falsifiable predictions

Memory trick: P-E-S-F
Process → Explanations → Self-correcting → Falsifiable

Critical Thinking

Judging the quality of information.

“judge evidence”

Discovery Science

Describes structures and processes that can be observed and measured.

-Discovery = Describe

hypothesis driven science

form explanations for HOW/WHY and starts w a questions/problem

-explanations for observations

Scientific Method

-formal process of inquiry used to investigate questions scientifically

Method = steps/process

7 scientific method steps

1 . Observation

2. Frame a question

3. Form a hypothesis

4. Make a prediction

5. Experiment

6. Gather results/data

7. Report findings

**O Q H P E D R

Hypothesis

tentative explanations formulated from observations and tested

-tentative= not certain, potential explanations

Falsifiable

hypothesis must be able to be shown wrong through experimentation or further observation.

-falsifiable = can prove it WRONG

Null Hypothesis

statement describing what would be observed if the hypothesis being tested is not correct.

-Null = NOTHING happened / hypothesis isn't correct

Theory

A well-supported explanation that has been repeatedly tested and successfully explains and predicts observations.

Theory = tested MANY times

Deductive Reasoning

general → specific.

DEDUCTIVE = DOWN
General idea → specific conclusion.

Inductive Reasoning

many observations to develop a general idea.

-INDUCTIVE = MANY observations

leads to hypotheses

tentative answer to well-framed question

Experiment

test that can support or falsify a prediction.

Variable

single characteristic that differs between groups in an experiment.

-differs from control group

Experimental Group

Group exposed to the variable being tested.

Experimental = gets the experiment

Control Group

Group that is identical to the experimental group except for the variable being tested.

CONTROL = comparison

2 types of data

1. qualitative

2. quantitative

qualitative data

descriptive

quantitative

numerical

Why don't scientists say an experiment "proves" a hypothesis?

⚠ EXAM WORDING:
❌ "The experiment proved the hypothesis."
✅ "The experiment supported the hypothesis/provided evidence."

Independent Variable

variable that stands alone and is changed/manipulated by the researcher.

- X-axis

IV = I change it

“causes change”

Dependent Variable

variable that depends on the independent variable.

- Y-axis

-DV = Depends on IV

“gets affected”

2 types of graphs

1. bar graph

2. scatter/line graph

prediction

IF -THEN

control

slight variation on the exp that is designed to rule out alternative explanations for the results

ideal control

variation in which everything is identical to the experiment expect ONE thing

can an experiment prove a hypothesis?

NO! only support

study of life

what, why, where, when, how living things do

no 2 organisms are…

identical

8 properties of life

1. Order

2. Sensitivity to stimuli

3. Reproduction

4. Adaptation

5. Growth & Development

6. Regulation

7. Homeostasis

8. Energy Processing

Order

Living things have complex but ordered systems.

Living = organized

Sensitivity to Stimuli

Organisms respond to changes in their environment.

Stimulus → Response

movement can be positive or negative

Irritability

ability of organisms to respond to changes in their immediate environment.

Chemotaxis

Movement in response to a chemical stimulus.

CHEMO = chemical

Phototaxis

Movement in response to light.

PHOTO = light

Reproduction

Creation of new generations of similar organisms.

Reproduction = make more life

Biogenesis → "Life comes only from life."

Adaptation

Characteristics that help organisms fit their environment; evolution by natural selection occurs in populations/species.

⚠ BIG TRAP:
An individual does NOT evolve. A population/species evolves.

Growth & Development

Increase in size, number of cells, complexity of cells, or all three.

Differentiation

Development of specialized cells that perform specific functions.

Differentiation = cells become different/specialized

Regulation

Organisms use regulatory mechanisms to coordinate internal functions.

Regulation = controlling what's happening inside

Homeostasis

Maintaining a steady internal environment despite changes in the external environment.

HOMEostasis = keeping the body's "home" stable

Energy Processing

Organisms acquire and use energy to maintain their organization through metabolic chemical reactions.

Energy = ability to do work

Metabolism

sum total of chemical reactions in an organism.

-how living things acquire energy

Metabolic pathway that builds larger molecules →

Requires an input of energy.

Anabolic pathway
→ Builds larger molecules from smaller molecules and requires energy.

🧠 ANABOLIC = ADD / BUILD 🧱

BUILD = needs energy

Metabolic pathway that breaks down large molecules →

Releases energy that cells can capture.

Catabolic pathway
→ Breaks down larger molecules into smaller molecules and releases energy.

🧠 CATABOLIC = CUT / BREAK ✂🧠 BREAK = releases energy

6 levels of livings things

Chemical → Cellular → Tissue → Organ → Organ System → Organism

Chemical Level

Atoms and molecules.

Cellular Level

Molecules, atoms, and organelles working together to perform cell functions.

Tissue Level

Collection of cells working together for a specific function.

Organ Level

Two or more tissues working together.

Organ System Level

Two or more organs working together.

Organism Level

Multiple organ systems working together to maintain the organism.

Two major ecosystem processes:

1. Cycling of nutrients

2. Flow of energy

🧠 Nutrients CYCLE 🔄

🧠 Energy FLOWS ➡

cell

lowest level of structure that can perform all activities required for life.

Cell = smallest unit of life

All organisms →

composed of cells.

DNA

Genetic information used by cells.

🧠 DNA = instructions

Cell membrane

Encloses cells and regulates passage of materials between the cell and its surroundings.

DNA building blocks

A, G, C, T

Prokaryotic Cell

→ Usually smaller, bacteria
→ → A cell that does not have a nucleus or membrane-bound organelles.

🧠 PRO = NO/ BEFORETHE NUCLEUS

Eukaryotic Cell

More complex
→ → A cell that has a nucleus and membrane-bound organelles.
→ Found in plants and animals

EU = TRUE nucleus

Biodiversity

diversity of life.

Taxonomy

Branch of biology that names and classifies species.

TAXONOMY = naming + organizing life

3 domains of life

1. bacteria

2. archaea

3. eukarya

“BAE”

bacteria

Prokaryotic

archaea

Prokaryotic

eukarya

Eukaryotic

Eukarya includes:

• kingdom Plantae 🌱

• kingdom Fungi 🍄

• kingdom Animalia 🐶

• Protists

Most plants, fungi, and animals are multicellular, while protists are generally single-celled

Binomial Name

Scientific name consisting of Genus + species.

G = Goes first + Gets capital

🧠 BI = 2 names

Phylogenetic Tree

branching diagram showing how living things are related through evolution.

🧠 Tree = family tree of life

The three major domains branch from a shared ancestor.

structure vs function

🧠 Structure = what it looks like
🧠 Function = what it does