IB Biology Unit 1 Review & Descriptive Statistics

Vocabulary flashcards covering the IB Biology One Pager notes, including levels of organization, emergent properties, processes of life, classification and taxonomy, biological variation, and descriptive statistics.

Atoms

The smallest unit of matter that cannot be broken down, composed of a nucleus, protons, electrons, and neutrons.

Simple Molecules

Chemical structures composed of a small number of atoms held together by covalent bonds, such as $H_2O$.

Macromolecules

Polymers composed of repeating monomers, including proteins and nucleic acids made of $C$, $H$, $O$, $N$, $P$, and $S$.

Subcellular Structures

Components and organelles within a cell, such as the nucleus and the Golgi apparatus.

Cells

The basic, smallest unit of life capable of performing biological functions, such as skin cells, neurons, blood cells, and bone cells.

Tissues

Groups of cells consisting of multiple cell types working together to perform a shared function, such as nervous, muscle, connective, and epithelial tissues.

Organs

Groups of tissues working together to perform a function, such as plant roots (anchor), stems (transport), and leaves (photosynthesis).

Organ Systems

Groups of organs that interact to perform major physiological functions, such as the nervous, respiratory, and muscular systems.

Organisms

Living individuals made up of interconnected parts, which can be unicellular or multicellular.

Populations

All individuals of a single species living within a particular area, characterized by genetic diversity and population dynamics.

Communities

All populations of different species coexisting in a particular area, characterized by inter-species interactions and biodiversity.

Ecosystems

Systems containing both biotic (living) and abiotic (non-living) components, characterized by energy flow across trophic levels.

Biomes

Expansive geographical regions defined by distinct climate influences and geographical distribution.

Biosphere

The global zone encompassing all of Earth's ecosystems and every level of biological organization, subject to global interactions and human impact.

Emergent Properties

Properties that arise only when components interact as a whole ($1+1 \neq 2$), meaning understanding one level of organization does not necessarily explain higher levels.

Global Workspace (conciousness)

Specialized molecules send messages into a vast network where these signals compete

Integrated Information (Phi)

A theoretical measure of consciousness that is higher in systems containing predominantly interconnected molecules, located in the hot zone at the back of the brain.

Homeostasis

The life process by which an organism adjusts to keep its internal environment stable, such as regulating internal temperature.

Metabolism

The totality of chemical reactions inside an organism that convert food into energy; absent in viruses (which are not life).

Nutrition

The acquisition of energy and matter, accomplished either by autotrophs (using the sun) or heterotrophs (using carbon).

Movement

A life process characterized as either motile (moving from place to place) or sessile (remaining in one place).

Excretion

The removal of metabolic waste from an organism, occurring via specialized waste systems in humans or across the cell membrane in unicellular organisms.

Growth and Development

An increase in size accompanied by structural and functional transformation throughout an organism's life span.

Response to Stimuli

The capacity of all living organisms to recognize and respond to environmental changes, such as through thermoreceptors.

Reproduction

The process by which living organisms create more life, occurring either sexually (two parents) or asexually (one parent).

Taxonomy

The branch of biology dedicated to classifying living things based on their natural relationships.

Binomial Nomenclature

The two-term naming convention for species where the genus is capitalized and the species is lowercase, written in italics or underlined, and abbreviated after initial use.

Dichotomous Key

A step-by-step tool used to identify biological species based on sequential pairs of observable traits.

Discrete Variation

Quantitative variation determined by genes that falls into distinct, separated categories, such as blood type or writing hand.

Continuous Variation

Quantitative variation influenced by environmental factors that forms a spectrum of values, such as height and body mass.

Intraspecies Variation

Variations occurring between individuals of the same or similar species, driven by mutation, gene flow, meiosis, and sexual reproduction.

Interspecies Variation

Differences in observable traits between entirely different biological species.

Descriptive Statistics

Brief numerical or graphical summaries of data sets that describe data, making patterns easier and quicker to comprehend.

Nominal Data

Qualitative data expressed in words without inherent order or ranking, best represented by the mode.

Ordinal Data

Qualitative data that follows a ranked order, best represented by the median.

Skew

A measure of the asymmetry of a distribution relative to the mean: perfect when $0$, moderate between $-0.5$ and $0.5$, and highly skewed around $-1$ or $1$.

Mean

A measure of central tendency used for unskewed quantitative data (skew value less than $1$) that is susceptible to outliers.

Median

The middle numerical value of magnitude, used for skewed quantitative data (skew value greater than $1$) or ordinal data.

Mode

The most frequently occurring data value, commonly used for qualitative, nominal categories.

Standard Deviation

A measure of spread paired with the mean; in unskewed data, approximately $68\%$ of values fall within $1$ standard deviation of the mean.

Range

A measure of spread calculated as the difference between the highest and lowest values, suitable for fewer than $5$ trials.

Interquartile Range

The width of the smallest interval containing the middle half ($50\%$) of the data, divided into quartiles and less affected by outliers.

Histogram

A graph representing the distribution of numerical data where the x-axis shows measurement ranges (bins) and the y-axis shows frequency per bin.

Bar Chart

A graphical display comparing quantitative data across distinct groups (x-axis) using mean values (y-axis), often with error bars displaying standard deviation.

Line/Curve Plot

A plot quantitatively comparing different groups on the x-axis with mean values on the y-axis, using error bars to show variation within a data set.

Box & Whisker Plot

A plot that compares data sets across comparative groups (x-axis) using median values (y-axis) and error bars/whiskers to show variation within each data set.