Unit Exam 1 Study Guide - Fall 2020

These flashcards cover key vocabulary and concepts from the Unit Exam 1 study guide based on Chapters 1, 2, and 3.

Organism

Each living individual is an organism.

Cell

The basic unit of life.

DNA

The molecule that all organisms have and is passed on to the next generation.

Ecosystem

The living and non-living components of an area.

Organelle

A membrane-bounded structure that has a specific function within a cell.

Homeostasis

The process by which a cell or organism maintains internal constancy and is an optimal balance.

Evolution

The genetic change over time in a population.

Domains of Life

The three domains of life are Bacteria, Archaea, and Eukarya.

Scientific method

The scientific method begins with observations and questions.

Hypothesis

Potential explanations for observations, which can be supported or falsified by data.

Independent variable

What is manipulated in an experiment.

Theory

An explanation for a natural phenomenon that is broader in scope than hypotheses.

Electrons

Subatomic particles that surround the atomic nucleus and are very small and fast.

Ion

A charged atom.

Protons

Subatomic particles that determine the atomic number.

Isotopes

Different forms of the same element that may vary in neutron number.

Covalent bond

A bond formed when atoms share electrons.

Protein

One of the four biomolecules essential for life.

Amino acid

The monomer for proteins.

Nucleotide

The monomer for DNA and RNA.

Polysaccharide

The polymer for carbohydrates.

Dehydration synthesis

The chemical reaction that joins monomers together.

Hydrolysis

A process that adds a water molecule.

Peptide bond

The type of bond formed when proteins are synthesized.

Secondary structure

A protein structure characterized by alpha helices and beta sheets.

Uracil

A nitrogenous base found only in RNA.

Triglyceride

A type of fat that has three fatty acid chains.

Unsaturated fatty acid

A type of fatty acid that is liquid at room temperature.

Surface area

Cells benefit from small size because it gives them more surface area.

Ribosomes

Organelles located on the rough endoplasmic reticulum and free in the cytoplasm.

Chloroplast

An organelle found in plant cells but not in animal cells.

Phospholipid bilayer

The structure that makes up the cell membrane.

Nucleus

The organelle that contains the DNA.

Nuclear envelope

The two-layered structure that mRNA is exported out through.

Golgi apparatus

An organelle that acts as a processing center.

Lysosomes

Organelles involved with cellular digestion.

Mitochondria

Organelle involved in cellular respiration.

Chloroplasts

Organelle involved in photosynthesis.

Cytoskeleton

A network of protein tracks and tubules found in eukaryotic cells.

Plasmodesmata

Structures that facilitate communication in plant cells.

Organ system

A group of different organs that work together, such as the circulatory system.

Metabolism

All chemical reactions that occur in a cell.

Domain Archaea

The domain to which prokaryotes belong.

Adaptations

Inherited characteristics or behaviors that enable survival and reproduction.

Organelles

Compartments within cells that carry out specific functions.

Atoms

Particles that make up molecules.

Heat

Energy lost from an ecosystem during energy transfers.

Taxonomy

The science of naming and classifying organisms.

Eukarya

The domain characterized by unicellular and multicellular organisms whose cells contain a nucleus.

Lipids

Types of molecules including phospholipids, triglycerides, and steroids.

Nucleotides

Molecules that make up nucleic acids like DNA and RNA.

Matter

Anything that takes up space.

Orbital

An area around the nucleus of an atom where an electron is likely to be found.

Cytoplasm

The part of a cell that contains various organelles.

Hydrophilic; hydrophobic

Describes the phosphate head of a phospholipid and the tails that face away from water.

Endoplasmic reticulum

A network of membranes winding through the cell.

Eukaryotic cells

Cells that contain membrane-bounded organelles and a nucleus.

True/False

A nucleotide is made of a phosphate group, a sugar, and a nitrogenous base.

Amino acids

Building blocks of proteins that have unique structures due to their R groups.

Prokaryotes

The most ancient forms of life.