BIOLOGY CHAPTER 1 2026

What is life?

What living things do

Seven characteristics of Life

1. Cells and Organization
2. Energy use and metabolism
3. Response to environmental changes
4. Regulation and homestasis
5. Growth and Development
6. Reproduction
7. Biological evolution

Cells and Organization

Organisms maintain an internal order. The simplest unit of organization is the cell.

autotrophy

organisns that make their own food through photosynthesis

heterotrophy

organisns that cannot make their own food and have to depend on others

environmental stimuli

the reaction of things in the environment

homeostasis

organisns regulaet their cells and bodies by maintaining the internal conditions

reproduction

reproducing and taking the genes of parents and sustaining life over generations

most important principle of biology

structure defines function

reductionism

complex systems are reduced to simppler components to make them more manageable to study

cell

the basic and smallest unit of life

tissue

a bunch of cells that have a common function

organs

a group of tissues that work together to perform a specific function

organ system

group of organs that have a relative function to each other

organism

independent living unit could be unicellular or multicellular

population

a group of organisms that are made of the same species

community

interaction of population and they are in a environment

ecosystem

interaction of communities

unity

united by an evolutionary past

emergent properties

are characteristics an entity gains when it becomes part of a bigger system

Reductionist approach

studies the isolated components of the living system

system biology

anaylsis of the interactions among the parts of a biological system

what do we find at the biological hierarchy

correlation between structure and functions

what is a cell

cell is the smallest unit of organization that is required for life

what is a eukaryotic cell

it has a membrane-enclosed organelles the largest is usually the nucleus

What is a prokaryotic cell

simple and smaller than eukaryotic and does not contain nucleus or any membrane-enclosed organelles

What is full form of DNA

deoxyribonucleic acid

What are genes

The unit of inheritence

Genere expression

the process of converting information from gene o cellular product

Genome

The complete genetic makeup of an organism

Genomics

Techniques used to analyze DNA sequences in genomes

Proteomes

The entire set of proteins expressed by a given cell

Photosynthetic organisms

the chenical energy generaed by plants and they are producers

What are consumers

organisms that feed on other organisms or their remains

feedback regulation

the output or product of a process

Negative Feedback

The response reducs that initual stimulus to preserve homeostasis

Positive Feedback

An end product speeds up its own production. It speeds up the direction of change

Climate Change

The extreme change in the weather as global warming

The three domains of life

Bacteria

Which two of the domains are prokaryotes

Bacteria and Archaea

What does the eukarya domain contain

- protists
- plants

How do new species evolve to pre-existing species

Through accumlation of mulations

What is Natural Selection

natural slection is when the orgnaism adapts to the environment by the ay they are.

Genetic exchange

species exchange cell genes in different ways this is rare

Horizontal gene transfer

when generes are transfers to another organism but not sexually

What does the tree of life focus on

vertical evolution

What does the web of life have the contribution of

horizontal gene transfer

What 2 points did Charles Darwin make

- Species showed evidence of "descent with modification" from common ancestors
- "Natural selection" is the mechanism behind descent with modification

What did Darwin' theory explain

the duality of unity and diversity

What is science

science is the observation

What are examples of different branches of biology

ecology

What does biologists describe

natural structure and pocesses

What are recorded observation called

data

What are the two different forms of data

qualitative and quantitative

What is qualitivative data

It doesn't have numbers but it is form of recorded descriptions

What is quantitative data

It is got by numerical measurememnts and organized in tables and graphs

what is hypothesis

education guess

what are two explanations that are outside the bounds of science

supernatural and religious

Is a hypotesis ever proven

no

What is a theory?

a broad explanation of some aspect of the natural world that is substantiated by a large body of evidence

What are the two key attributes of a theory

- Consistency with a vast amount of known data
- Ability to make many correct predications

What are the 2 general aprooches used by biologist

1. Discovery-based science
2. Hypothesis testing

What is the goal of discovery-based science

gathering information

Scientific Method

steps that scientist use to test their thinking and give it validation

The steps of scientific method

1. Make observation
2. Formulate hypothesis
3. Give a testable predication
4. Conduct a critical experiment
5. Draw conclusions and make revisions as needed

Negative statement

proposes thhat their are no relationship between two factors

Null hypothesis

a counter-argument hypothesis