Lab `1-50

For exam 1

Experimental variable (also known as independent)

A variable that is manipulated or changed in an experiment to observe its effects on a dependent variable.

Dependent variable

The variable you use to determine your results

Controlled variable

A variable that is kept constant throughout an experiment to ensure that any changes in the dependent variable are due to the experimental variable.

Treatment

A specific condition or set of procedures applied to the experimental group in an experiment, which is compared against a control group to assess effects on the dependent variable.

Controlled treatment

Refers to a specific set of procedures or conditions applied to the control group in an experiment for comparison with the experimental group.

Covalent

A type of chemical bond where pairs of electrons are shared between atoms. Covalent bonds typically form between nonmetal atoms and can result in the formation of molecules.

Electron

A negatively charged subatomic particle that orbits the nucleus of an atom, playing a key role in chemical bonding and electricity.

Solid lines represent?

the strong covalent bonds between atoms in a molecular structure.

Partially charged atom

An atom that has an uneven distribution of electron density, resulting in a slight positive or negative charge. This occurs in polar covalent bonds where electrons are not equally shared.

Polar molecule

A molecule that has a partial positive charge on one end and a partial negative charge on the other end due to an unequal sharing of electrons.

Polar molecules are attracted to themselves and other?

partially charged molecules

Hydrogen bond

A weak attraction between a partially positive hydrogen atom and a partially negative atom, often oxygen or nitrogen, in another molecule.

Hydrogen bonds are not?

Chemical bonds, merely actractions that stabilize molecular structures.

S+

partially positive

S-

partially negative

Polar molecules in a liquid that are attracted to one another, what is this called?

Cohesion

Strengthening bonds at the top of a surface are called?

Surface tension.

Detergents have hydrophobic (non-polar) end, and a hydrophilic (polar) end

These disrupt the hydrogen bonds in the water, which can reduce the effects of surface tension

Definition of Solute?

The substance that is being dissolved

Definition of Solvent

Is the dissolving medium

what is a Solution?

A homogeneous mixture formed when a solute is dissolved in a solvent.

Osmosis

The movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Selectively permeable membrane

A barrier that allows certain molecules or ions to pass through while blocking others, essential for maintaining cellular homeostasis.

concentration gradiant

When there is a greater concentration of a substance in one area and less in another

Diffusion

The process by which molecules spread from areas of high concentration to areas of low concentration.

What does a chemical reaction begin with

one or more reactants that are altered to produce one or more products

reactants

A starting substance is a chemical reaction that undergoes a transformation to become a product

Catalase

An enzyme that catalyzes the decomposition of hydrogen peroxide into water and oxygen.

enzym

specialized biological molecules—mostly proteins, though some are RNA—that act as catalysts to speed up chemical reactions in living thing

Enzyms belong to a part of molecules called?

Catalysts that facilitate biochemical reactions.

Enzymes can bind more than one molecule called?

substrates

Specificity

Each enzyme can only bind to a specific substrate(s) due to its unique active site structure.

Shape of an enzyme is determined by

its amino acid sequence and folding.

How can we measure the degree of enzyme activity?

Enzyme activity can be measured by assessing the rate of substrate conversion to product, usually by monitoring changes in substrate or product concentration over time.