Biology Unit 1 Test

Neutral Atoms

have the same number of protons and electrons

Ions

charged particles, unbalanced

Oxidation

Loss of electrons

Reduction

gain of electrons

Elements

any substance that cannot be broken down into simpler substances

Organic molecules contain primarily these elements

C,H,O,N (carbon, hydrogen, oxygen, nitrogen)

Covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

Types of covalent bonds

polar and nonpolar

polar covalent bond

unequal sharing of electrons

nonpolar covalent bond

a covalent bond in which the electrons are shared equally by the two atoms

Why is water so important to life?

It's the perfect liquid medium in which to dissolve nutrients for ingestion or wastes for excretion, to transport important chemicals. This is primarily because it is polar and able to hydrogen bond with itself, but also because it can dissolve ionic bonds.

ionic bond

A chemical bond resulting from the attraction between oppositely charged ions.

Biological Molecules contain primarily:

Carbon bonded to carbon, or carbon bonded to other molecules

dehydration synthesis

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule. Energy RELEASE

Biologically important macromolecules

carbohydrates, lipids, proteins, nucleic acids

Macromolecules are often....

Polymers (long molecules built by linking together small, similar subunits (monomers))

Carbohydrates

molecules that contain only carbon, hydrogen, and oxygen in a 1:2:1 ratio (CH2O)

examples of carbohydrates

sugars, starches, and glucose

Monosaccharides

Single sugar molecules

Isomers

Compounds with the same formula but different structures.

Dissacharides

A sugar containing two monosaccharides, joined by a covalent bond (dehydration synthesis). Example: sucrose which is fructose + glucose.

examples of disaccharides

sucrose, lactose, maltose

Polysaccharides

long chains of sugars

examples of polysaccharides

plants starch, glycogen

What do carbohydrates do?

Transport and store energy—mostly transport disaccharides.

Alpha vs. Beta glucose, what is the difference between them, why are they important?

They are isomers of each other, meaning that they have the same molecules in them, but have different structures. The only difference between them is the location of their -H and -OH groups. However, this small change makes alpha glucose able to be digested by humans, and beta glucose basically just fiber that is unable to be digested.

Biology's Central Dogma

The transfer of information from generic material into another macromolecule, which is protein

DNA -> RNA = ?

transcription

RNA -> Protein = ?

translation

2 types of nucleic acids

DNA and RNA

Functions of DNA and RNA

Primarily specialized for storage, transmission, and use of genetic information

DNA (deoxyribonucleic acid)

Encodes information used to assemble proteins

RNA (ribonucleic acid)

Reads DNA-encoded information to direct protein synthesis.

What are nucleotides?

Monomers of Nucleic acids (basically the building blocks of them)

What are nucleotides made of?

Sugar + Phosphate + Nitrogenous base

Sugar in DNA

deoxyribose

Sugar in RNA

Ribose

All nitrogenous bases

adenine, guanine, cytosine, thymine, uracil

Examples of purines are...

Adenine (A) and Guanine (G)

examples of pyrimidines

Thymine (T), Uracil (U), Cytosine (C)

Which nitrogenous bases are used in DNA?

A, G, T, C

Which nitrogenous bases are used in RNA?

A, G, U, C

What does adenine pair with in DNA?

Thymine (T)

What does guanine pair with in DNA?

Cytosine (C)

What does adenine pair with in RNA?

Uracil (U)

What is the function of RNA?

Read DNA strand and direct protein synthesis

What is ATP?

adenosine triphosphate, the primary energy currency of the cell

What are proteins?

polymers of amino acids

What are the functions of proteins?

enzyme catalysis, defense, transport, support, motion, regulation, storage

What is an enzyme?

a protein molecule that speeds up chemical reactions, without itself being destroyed or altered upon the completion of the reaction.

What is the monomer of a protein?

amino acids (20)

What is the amino acid structure of a protein?

a central carbon atom surronded by,

- an amino group (-NH2)

- a carboxyl group (-COOH)

- single hydrogen

- variable R group

How many amino acids are there?

20 amino acids, grouped by major classes relating to their charge and polarity

What is a peptide bond?

bond between amino acids

A protein is one or more long chains of ...

amino acids joined by peptide bonds

Why does protein structure matter?

Protein function is determined by its shape

What are the different types of protein structures?

Primary, secondary, tertiary, quaternary

primary protein structure

specific sequence of amino acids

secondary protein structure

folding of amino acid chains

tertiary protein structure

folded shape of polypeptide chain

quaternary protein structure

interactions between multiple polypeptide chains/subunits

Unfolding proteins is called ...

denaturation

What is denaturation?

a structural change in a protein that results in a loss of its biological properties

What can cause denaturation?

any extreme change in temperature or pH that can affect the shape of a protein

Why do children need a more varied diet than adults?

children dont make a lot of amino acids that adults do, so they need to aquire them through food.

Lipids are

groups of molecules that contain long C-H tails, and are insoluble in water.

The two main catogories of lipids are

Fats or triglycerides, and phospholipids

Fats (triglycerides) are composed

1 glycerol and 3 fatty acids. Fatty acids are long hydrocarbon chains

What is a saturated fat?

all internal carbon atoms are bonded to at least 2 H atoms

What is an unsaturated fat?

acid in which there is at least one double bond between successive C atoms

polyunsaturated fats

contains more than one double bond

Are unsaturated fats solid or liquid at room temperature?

Liquid, because they are less dense (less hydrogen bc of double bond)

Are triglycerides good energy storage molecules?

Yes, they are an excellent souce of energy. Fats have around 9 kcal/gram while carbs have around 4

Animal fats are saturated, are they solid or liquid at room temp?

Solid, because they are more dense.

Plant fats are unsaturated, are they solid or liquid at room temp?

liquid, becuase they are less dense.

What is a phospholipid?

A molecule that is a constituent of the inner bilayer of biological membranes.

What type of head do phospholipids have?

A polar, hydrophilic head.

What type of tail do phospholipids have?

A nonpolar, hydrophobic tail.

Properties of Life

Cellular organization

Ordered complexity

Sensitivity

Growth, development, and reproduction

Energy utilization

Homeostasis

Evolutionary adaptation

What does cell theory state about living things?

All living things are made up of cells.

What is the basic unit of structure and function in living things according to cell theory?

Cells are the basic units of structure and function in living things.

How are new cells produced according to cell theory?

New cells are produced from existing cells.

prokaryotic cell

A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea.

Eukaryote

A cell that contains a nucleus and membrane bound organelles (HUMANS)

saturated fats

fats that are solid at room temperature, no double bonds

unsaturated fats

A fat that is liquid at room temperature and found in vegetable oils, nuts, and seeds. DOUBLE BOND

What is the basic unit of life according to cell theory?

Cells are the most basic unit for function in all living organisms.

What are the common features of all cells?

All cells have a cytoplasm, ribosomes, and a plasma membrane.

What distinguishes prokaryotic cells from eukaryotic cells?

Prokaryotic cells lack a membrane-bound nucleus and are simpler than eukaryotic cells.

What are the two domains of prokaryotes?

Archaea and Bacteria.

What is a hallmark feature of eukaryotic cells?

Compartmentalization achieved through membrane-bound organelles and an endomembrane system.

What is the function of the nucleus in a cell?

The nucleus contains the genetic information of the cell.

What are the two types of molecules allowed through the nuclear envelope?

The nuclear envelope allows certain molecules through nuclear pores, though the specific types are not detailed in the notes.

What is the role of ribosomes in a cell?

Ribosomes are the sites of protein synthesis.

What organelles contain their own DNA?

Mitochondria and chloroplasts.

What is the primary function of mitochondria?

Mitochondria produce energy for the cell.

What process occurs in mitochondria?

Cellular respiration, converting biochemical energy to ATP.

What is the equation for cellular respiration?

C6H12O6 (s) + 6 O2 (g) → 6 CO2 (g) + 6 H2O (l) + heat + 38 ATP.

What is the function of chloroplasts?

Chloroplasts convert light energy into chemical energy through photosynthesis.

What is the equation for photosynthesis?

2n CO2 + 2n H2O + photons → 2(CH2O)n + 2n O2.