Biology Unit 1 Test review (TOPICS ALL IN ONE YIPPEE)

What is biology?

The study of life and living organisms.

What are the characteristics of life?

Made of cells, use energy, grow/develop, reproduce, respond to stimuli, maintain homeostasis, and contain genetic information.

What is homeostasis?

Maintaining a stable internal environment.

What is the difference between a hypothesis and a theory?

A hypothesis is a testable explanation; a theory is a well-supported explanation based on lots of evidence.

What are the three main subatomic particles?

Protons (+)

Neutrons (0)

Electrons (-)

Where are protons, neutrons, and electrons located?

Protons/neutrons = nucleus; electrons = outside the nucleus.

What does the atomic number tell you?

The number of protons.

How do you find the number of electrons in a neutral atom?

Electrons = protons = atomic number.

What is a chemical bond?

An attraction that holds atoms together.

What are the main types of chemical bonds?

Ionic, covalent, and hydrogen bonds.

What are the four major biomolecules?

Carbohydrates, lipids, proteins, and nucleic acids.

What are carbohydrates mainly used for?

Quick energy and some structural support.

What are lipids mainly used for?

Long-term energy storage, insulation, cell membranes, and hormones/signaling.

What are proteins made of?

Amino acids.

What are proteins used for?

Enzymes, structure, transport, movement, defense, and signaling.

What are nucleic acids made of?

Nucleotides.

What are DNA and RNA?

Nucleic acids that store/use genetic information.

What is dehydration synthesis?

Builds a larger molecule by removing water.

What is hydrolysis?

Breaks a larger molecule apart by adding water.

What is an enzyme?

A protein that speeds up chemical reactions.

What does an enzyme do to activation energy?

Lowers it, making the reaction happen more easily.

What is the substrate?

The molecule an enzyme acts on.

What is the active site?

The part of an enzyme where the substrate binds.

What factors can affect enzyme activity?

Temperature, pH, and substrate concentration.

What is a nucleotide?

The monomer of nucleic acids; it contains a sugar, phosphate group, and nitrogenous base.

What are the three parts of a DNA nucleotide?

Deoxyribose sugar, phosphate group, and nitrogenous base.

What are DNA's four nitrogenous bases?

Adenine (A), thymine (T), cytosine (C), and guanine (G).

What are the DNA base-pairing rules?

A pairs with T; C pairs with G.

What is DNA's structure?

A double helix made of two complementary strands.

What happens during DNA replication?

DNA unwinds, the strands separate, and each original strand is used as a template to build a new complementary strand.