Living Environment Regents Review

A comprehensive vocabulary flashcard set covering biology topics for the Living Environment Regents exam, including cell biology, homeostasis, genetics, reproduction, evolution, ecology, and human impact.

Cells

The smallest units of life.

Organelles

The structures inside the cell.

Nucleus

Contains DNA (genetic information) that controls the production of proteins.

Ribosomes

Structures that read the message sent from DNA and place amino acids in the correct order to form a protein.

Mitochondria

The site of cellular aerobic respiration where $ATP$ is made for metabolic activities.

Vacuoles

Structures used to store food or wastes; plant cells have a super large version to store water and sugar.

Cytoplasm

Fluid (mostly water) where many chemical reactions take place.

Cell Membrane

Controls what goes in (nutrients and $O_2$) or out ($CO_2$ and wastes) of the cell.

Selectively permeable

A property of the cell membrane where only certain substances can pass through.

Diffusion

The movement of molecules from a high concentration to a low concentration with no energy required.

Osmosis

The diffusion of water.

Active Transport

The movement of molecules from a low concentration to a high concentration requiring energy in the form of $ATP$.

Receptor Molecules

Molecules on the cell membrane whose shape determines what substances can attach to and be brought into the cell.

Chloroplasts

The site of photosynthesis in plant cells containing the green pigment chlorophyll.

Autotrophic Organisms

Organisms that take in inorganic molecules like $CO_2$ and $H_2O$ to form complex organic compounds like glucose ($C_6H_{12}O_6$).

Heterotrophic Organisms

Organisms that cannot make their own food and must rely on other organisms for food.

Transport

The process by which materials like nutrients, wastes, and hormones are distributed throughout the cell or body.

Metabolism

All the chemical reactions that occur within an organism.

Synthesis

The process of making materials in the body, such as using nutrients to make proteins.

Excretion

The process of getting rid of toxic waste products from cellular processes.

Homeostasis

The internal stability that all organisms maintain.

Photosynthesis

The energy-storing process that happens in chloroplasts where light energy is converted into chemical energy represented by $H_2O + CO_2 \rightarrow C_6H_{12}O_6 + O_2$.

Stomates

Holes on the bottoms of leaves that open to let $CO_2$ in and close to conserve water.

Guard cells

Special cells that control the opening and closing of the stomates.

Cellular Respiration

The energy-releasing process occurring in mitochondria represented by $C_6H_{12}O_6 + O_2 \rightarrow H_2O + CO_2 + ATP$.

Pathogens

Disease-causing organisms such as viruses, bacteria, fungi, microorganisms, and protists.

Antigens

Protein name tags with a special shape that white blood cells recognize on pathogens.

White Blood Cells

Cells that produce antibodies with a special shape to recognize and destroy pathogens.

Vaccines

Dead or weakened pathogens injected into the body so white blood cells can practice making antibodies.

Feedback Mechanisms

Systems that maintain homeostasis by regulating the amount of sugar, water, or calcium in the body.

Dynamic Equilibrium

The constant small corrections that must occur to maintain homeostasis.

Enzymes

Specially shaped proteins that act as catalysts to increase the rate of biochemical reactions.

DNA

Deoxyribonucleic acid; it resides in the nucleus and carries instructions for making proteins using bases $A$, $T$, $C$, and $G$.

Genes

DNA's sequence of bases that code for a protein; they can be turned on or off (expressed) depending on the environment.

Mutation

An error in the DNA sequence that causes a mistake in the order of amino acids in a protein.

Selective Breeding

Humans choosing specific organisms to mate in order to obtain desired traits in offspring.

Recombinant DNA

DNA made by cutting genes using restriction enzymes and inserting them into another organism's DNA.

Gel electrophoresis

A technique where fragments of DNA are separated by size as they move toward a positive cathode.

Asexual Reproduction

Reproduction where one organism divides into two or more genetically identical offspring via mitosis.

Mitosis

Cell division used to produce identical cells for growth, repair, or asexual reproduction.

Sexual Reproduction

Reproduction involving two parents donating genes to form a new individual with increased genetic variation.

Meiosis

Cell division that produces gametes (sex cells) containing half the original DNA.

Fertilization

The fusion of two gametes to form a zygote, maintaining the correct chromosome number.

Placenta

A temporary organ that provides nutrients, gas exchange, and waste removal for a fetus.

Differentiation

The process where cells specialize and become different depending on which genes are turned on or off.

Evolution

Change over time in the frequency of selected genes within a population of organisms.

Natural Selection

The theory that organisms with genes better adapted to their environment (Adaptive Value) survive and reproduce.

Evolutionary Tree

A diagram that illustrates the common ancestry and change of species over time.

Ecosystem

The interaction between living (biotic) and nonliving (abiotic) factors in a given area.

Decomposers

Organisms like bacteria and fungi that break down dead material to recycle nutrients like nitrogen.

Energy Pyramid

A diagram showing that 90% of energy is lost to metabolic activities at each level as it is passed through a food chain.

Carrying Capacity

The amount of organisms that can be supported by a habitat depending on available food or space.

Ecological Succession

The process by which ecosystems evolve and change over time, such as a field turning into a forest.

Trade-off

A decision involving weighing the good and bad influences of an action on the environment.

Independent Variable

The variable in an experiment that is changed or controlled to test the effects on the dependent variable.

Dependent Variable

The variable being tested and measured in a scientific experiment.

Cell Theory

The theory that all living things are made up of cells, and cells are the basic unit of life.

Prokaryotic Cells

Simpler cells without a nucleus; examples include bacteria.

Eukaryotic Cells

Complex cells with a nucleus; examples include plant and animal cells.

Cytoskeleton

A network of fibers that helps maintain the cell's shape and aids in movement.

Endoplasmic Reticulum (ER)

A network of membranes involved in protein and lipid synthesis.

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins for secretion.

Lysosomes

Organelles that contain digestive enzymes to break down waste and cellular debris.

Permeability

The ability of a membrane to allow substances to pass through.

Hypotonic Solution

A solution with a lower concentration of solutes compared to another solution, causing cells to swell.

Hypertonic Solution

A solution with a higher concentration of solutes compared to another solution, causing cells to shrink.

Isotonic Solution

A solution that has the same concentration of solutes as another solution, resulting in no net movement of water.

Facilitated Diffusion

The process of passive transport of molecules across a cell membrane via special proteins.

Exocytosis

The process by which a cell expels materials in vesicles.

Endocytosis

The process by which cells take in materials by engulfing them with the cell membrane.

Cell Cycle

The series of phases that a cell goes through to grow and divide.

Glycolysis

The first step of cellular respiration where glucose is broken down in the cytoplasm to produce ATP.

Krebs Cycle

A series of chemical reactions in the mitochondria that produce energy through the oxidation of acetyl-CoA.

Anaerobic Respiration

The process of producing cellular energy without oxygen.

Gene Expression

The process by which information from a gene is used to produce a functional gene product, usually a protein.

Biotechnology

The use of biological processes, organisms, or systems to develop products and technologies.

Stem Cells

Undifferentiated cells with the potential to develop into different cell types.

Cloning

The process of producing genetically identical individuals of an organism.

Cells

The smallest units of life.

Organelles

The structures inside the cell.

Nucleus

Contains DNA (genetic information) that controls the production of proteins.

Ribosomes

Structures that read the message sent from DNA and place amino acids in the correct order to form a protein.

Mitochondria

The site of cellular aerobic respiration where $ATP$ is made for metabolic activities.

Vacuoles

Structures used to store food or wastes; plant cells have a super large version to store water and sugar.

Cytoplasm

Fluid (mostly water) where many chemical reactions take place.

Cell Membrane

Controls what goes in (nutrients and $O_2$) or out ($CO_2$ and wastes) of the cell.

Selectively permeable

A property of the cell membrane where only certain substances can pass through.

Diffusion

The movement of molecules from a high concentration to a low concentration with no energy required.

Osmosis

The diffusion of water.

Active Transport

The movement of molecules from a low concentration to a high concentration requiring energy in the form of $ATP$.

Receptor Molecules

Molecules on the cell membrane whose shape determines what substances can attach to and be brought into the cell.

Chloroplasts

The site of photosynthesis in plant cells containing the green pigment chlorophyll.

Autotrophic Organisms

Organisms that take in inorganic molecules like $CO_2$ and $H_2O$ to form complex organic compounds like glucose ($C_6H_{12}O_6$).

Heterotrophic Organisms

Organisms that cannot make their own food and must rely on other organisms for food.

Transport

The process by which materials like nutrients, wastes, and hormones are distributed throughout the cell or body.

Metabolism

All the chemical reactions that occur within an organism.

Synthesis

The process of making materials in the body, such as using nutrients to make proteins.

Excretion

The process of getting rid of toxic waste products from cellular processes.

Homeostasis

The internal stability that all organisms maintain.

Photosynthesis

The energy-storing process that happens in chloroplasts where light energy is converted into chemical energy represented by $H_2O + CO_2 \rightarrow C_6H_{12}O_6 + O_2$.