Biology Q1 Cumulative Review

Covalent

Atoms sharing electrons

Polar covalent

Electrons shared UNEQUALLY, causing partial negative and positive charges

Ionic

Atoms losing or gaining electrons, resulting in charged ions

Cation

Positively charged ion

Anion

Negatively charged ion

Hydrogen bonding

Forms between slightly negative and positive sides of different molecules

Van der Waals forces

Weak intermolecular forces dependent on distance between atoms/molecules

Cohesion

Water attracted to another water molecule

Adhesion

Water attracted to a different molecule

Capillary action

Allows trees to transport water from roots to leaves

Surface tension

Barrier on water surface caused by cohesion, creating an 'invisible skin'

High Specific Heat capacity

Water's ability to absorb/release energy before temperature changes

Ice is less dense than liquid water

Due to rigid hydrogen bonds, occupying more space

Activation energy

Minimum energy needed for a reaction to occur

Catalyst

Substance speeding up a reaction without being consumed

Enzymes

Biological catalysts, usually proteins, speeding up reactions in cells

Active site

Region where reactants bind on an enzyme

Denatured enzymes

Enzymes losing shape due to temperature or pH changes

Carbohydrates

Monosaccharides (1:2:1 ratio of C:H:O) forming polysaccharides for energy and structure

Lipids

Fatty acids and glycerol forming triglycerides, phospholipids, and steroids for various functions

Proteins

Amino acids forming polypeptides and proteins with diverse functions and shapes

Nucleic Acids

Nucleotides with sugar, phosphate group, and nitrogenous base forming DNA & RNA for genetic information storage

Energy Flow

Unidirectional energy flow in ecosystems with matter cycling; <1% of sun's energy captured by producers

Trophic Level

Each level in a food chain or food web where organisms obtain their energy

Autotrophs/Producers

Organisms that produce their own food/energy from inorganic sources

Photosynthesis equation

6CO2 + 6H2O →C6H12O6 + 6O2

Chemosynthetic organisms

Organisms that use chemical energy to create food, often in the absence of sunlight

Consumers/Heterotrophs

Organisms that cannot produce their own food, relying on other organic sources for nutrition

Decomposers

Organisms that chemically break down organic matter, recycling nutrients

Detritivores

Organisms that feed on dead and decomposing organic matter

Scavengers

Organisms that consume decaying biomass, often meat or rotting plant material

Carbon Cycle

The cycle of carbon through the atmosphere, biosphere, geosphere, and hydrosphere

Nitrogen Cycle

The cycle of nitrogen through different forms and reservoirs in the environment

Phosphorous Cycle

The cycle of phosphorus through the environment, including its various forms and reservoirs

Water Cycle

The continuous movement of water on, above, and below the surface of the Earth

Carrying capacity

The maximum number of individuals of a species that an ecosystem can sustain indefinitely

Limiting factors

Factors, either biotic or abiotic, that restrict the growth of a population

Density-dependent limiting factors

Factors that impact population growth based on the population size

Density-independent limiting factors

Factors that affect population growth regardless of population size

Human Population Growth

The exponential increase in the global human population over the last few centuries

Ecosystem Resilience

The ability of an ecosystem to recover after a disturbance

Succession

The process of ecological change in an ecosystem over time

Symbiotic Relationships

Close and long-term interactions between different species in an ecosystem