Biology Quiz: Macromolecules and Water Properties

A microscope that provides a 3D view of an object's surface, useful for observing the external features of specimens. Commonly used for dissecting and studying living specimens.

Allows viewing of both internal and external features of specimens.

A powerful microscope that uses a beam of electrons to create highly detailed images, providing a 3D view of the surface. Used for imaging external structures of inanimate specimens.

A microscope that transmits a beam of electrons through a thin specimen, generating a 2D image of the internal structure. Offers the highest magnification.

All microscopes use lenses to magnify objects, but the type of lens and the method of illumination vary depending on the microscope's purpose.

Water is a molecule made up of two hydrogen atoms bonded to one oxygen atom. Due to oxygen's higher electronegativity, the oxygen side of the molecule carries a slight negative charge, while the hydrogen side carries a slight positive charge.

The uneven distribution of charge in a water molecule, causing one side to be slightly positive and the other slightly negative.

A weak attraction between a positively charged hydrogen atom and a slightly negative atom in another molecule.

The tendency of water molecules to stick together due to hydrogen bonding. It creates surface tension, allowing water to resist external forces.

The ability of water to resist being stretched or broken due to the strong cohesive forces between molecules.

The ability of water to resist temperature changes due to hydrogen bonds absorbing heat.

The property of water that makes it less dense as a solid (ice) than as a liquid, allowing ice to float.

The ability of water to dissolve many substances due to its polar nature and ability to form hydrogen bonds.

A large molecule made of repeating smaller units called monomers.

Lipids, also known as fats, are molecules made of carbon, hydrogen, and oxygen. They play a key role in storing energy, forming cell membranes, and providing insulation.

Lipids are nonpolar molecules, meaning they don't mix well with water. This is because they have a hydrophobic (water-fearing) nature.

Proteins are complex organic molecules made up of carbon, hydrogen, oxygen, and nitrogen. They are essential for various functions in the body.

Nucleic acids are long polymers made of smaller units called nucleotides. They store and transmit genetic information.

The pH scale measures the acidity or alkalinity of a solution. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic.

The specific region on an enzyme where substrates bind to initiate a reaction.

Molecules that enzymes work on, binding to the enzyme's active site.

The process of breaking down molecules into simpler ones.

The process of building up complex molecules from simpler ones.

The minimum amount of energy needed for a chemical reaction to start.

A substance that speeds up a chemical reaction by lowering the activation energy needed to start the reaction.

A biological catalyst, usually a protein, that speeds up specific chemical reactions in living organisms.

The range of temperatures and pH values at which an enzyme works most effectively.

The theory that all living organisms are made up of cells, and that all cells come from pre-existing cells.

Prokaryotes are tiny, single-celled organisms that lack membrane-bound organelles, like a nucleus. Their DNA is in a circular shape, and they may have a tail-like flagellum for movement.

Eukaryotes are cells that have a nucleus and other membrane-bound organelles. They can be single-celled or part of multicellular organisms, like plants and animals.

Passive transport moves substances across the cell membrane without using energy. It follows the concentration gradient, moving from high to low concentration.

Active transport requires energy (ATP) to move substances against the concentration gradient, from low to high concentration.

The cell membrane is a semipermeable barrier that controls what enters and exits the cell. It only allows certain molecules to pass through.

The cell membrane is a flexible barrier that surrounds a cell, controlling what enters and exits. It's composed of a phospholipid bilayer, with proteins embedded within. Think of it like a gatekeeper.

A cell in an isotonic solution experiences no net movement of water because the solute concentrations inside and outside are equal. Imagine the cell is like a sponge, neither absorbing nor releasing water.

In a hypotonic solution, the concentration of solutes is higher inside the cell, so water moves into the cell. Think of the cell as a sponge in water - it absorbs it!

A cell in a hypertonic solution loses water to the environment because the solute concentration is higher outside the cell. Imagine the cell as a sponge in salty water - it dries out.

The cell membrane is selectively permeable, meaning it allows some substances to pass through while blocking others. Imagine it like a net that catches only certain fish.

A process that occurs in the absence of oxygen, producing a small amount of energy (ATP) and byproducts like lactic acid or alcohol.

The process of breaking down glucose in the absence of oxygen, producing lactic acid as a byproduct.

The process of breaking down glucose in the absence of oxygen, producing alcohol and carbon dioxide as byproducts.

The process of breaking down glucose in the presence of oxygen, producing a large amount of energy (ATP) and water as byproducts.

Glycolysis is the first stage of cellular respiration, where glucose is broken down into pyruvate. It occurs in the cytoplasm and does not require oxygen.

The Krebs cycle, also known as the citric acid cycle, is the second stage of cellular respiration. It occurs in the mitochondria and involves the breakdown of pyruvate to produce ATP, CO2, and energy carriers.

The electron transport chain is the final stage of cellular respiration. It occurs in the mitochondria and uses energy carriers from previous stages and oxygen to produce large amounts of ATP.

Cellular respiration is an exothermic process, meaning it releases energy. This is in contrast to photosynthesis, which is an endothermic process that absorbs energy from sunlight.