Comprehensive BIOL 101: Characteristics, Cell Structure, Chemistry, and Organic Molecules

What is Science?

Science is the systematic study of the structure and behavior of the physical and natural world through observation and experiment.

What is Biology?

Biology is the study of life.

What are the 7 characteristics of life?

Organized, Acquire materials and energy, Reproduce, Respond to stimuli, Homeostatic, Grow & develop, Adapt to environment.

What is the smallest unit of life?

Cell.

What is the order of levels of organization from smallest to largest?

Atom → Molecule → Cell → Tissue → Organ → Organ System → Organism → Population → Community → Ecosystem → Biosphere.

What is Taxonomy?

Taxonomy is the discipline of identifying and grouping organisms.

What is Systematics?

Systematics is the study of evolutionary relationships among organisms.

What is the hierarchical classification order?

Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species.

What are the three domains of life?

Bacteria (Prokaryote), Archaea (Prokaryote), Eukarya (Eukaryote).

What is binomial nomenclature?

A system for naming species using the format Genus species.

What is the scientific method?

Observation → Hypothesis → Investigation/Experiment → Conclusions → Communication.

What is a hypothesis?

A proposed explanation for an unexplained phenomenon that must be testable.

What is a scientific theory?

A scientific theory joins well-supported hypotheses and has support from many observations, experiments, and data.

What is matter?

Matter is anything that takes up space and has mass.

What are the three states of matter?

Solid, Liquid, Gas.

What elements make up about 95% of organisms by weight?

Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur (CHNOPS).

What is an atom?

An atom is the smallest part of an element that displays the properties of that element.

What are the three subatomic particles?

Proton (+), Neutron (0), Electron (−).

What is an isotope?

Isotopes are atoms of the same element with different numbers of neutrons.

What is radiocarbon dating?

A method to estimate the age of an organism using the decay of Carbon-14.

What is the octet rule?

Atoms tend toward a full outer orbital.

What is a molecule?

A molecule is two or more atoms bonded together.

What is an ionic bond?

An ionic bond is the attraction between oppositely charged ions formed by the transfer of electrons.

What is a covalent bond?

A covalent bond occurs when atoms share electrons.

What is the difference between polar and nonpolar covalent bonds?

Nonpolar covalent bonds share electrons equally, while polar covalent bonds share electrons unequally.

What is a hydrogen bond?

A hydrogen bond occurs due to attractions between partially positive and partially negative regions.

What is the significance of water in biology?

Water is crucial as it makes up 70-90% of organisms and has unique properties due to its polarity.

What is pH?

The pH scale measures acidity or alkalinity, ranging from 0 (acidic) to 14 (alkaline).

What is cell theory?

Cell theory states that all organisms are composed of one or more cells, cells are the basic living unit of structure and function, and all cells come only from other cells.

What is the difference between prokaryotic and eukaryotic cells?

Prokaryotic cells lack a membrane-bound nucleus and organelles, while eukaryotic cells have both.

Why are cells small?

Cells are small to maintain a high surface area-to-volume ratio for efficient material movement.

What is the main function of the plasma membrane?

Controls what enters and leaves the cell.

What does the nucleus store?

DNA.

What is the function of the nucleolus?

rRNA synthesis.

What do ribosomes do?

Make proteins.

What is the function of the rough endoplasmic reticulum (ER)?

Protein modification.

What does the smooth ER produce?

Phospholipids and steroids; stores Ca²⁺.

What is the role of the Golgi apparatus?

Packages proteins and lipids.

What do vesicles do?

Transport materials.

What is the function of lysosomes?

Break down old or foreign material.

What do peroxisomes break down?

Lipids.

What is the main function of mitochondria?

Produce ATP through cellular respiration.

What is the role of the cytoskeleton?

Provides structure, movement, and aids in cell division.

What is the function of the centrosome?

Microtubule assembly and disassembly.

What is the role of centrioles?

Cell division.

What is the function of cilia?

Movement; many and short.

What is the function of flagella?

Movement; few and long.

What is the main component of the cell wall in plant cells?

Cellulose and lignin.

What is the function of chloroplasts?

Photosynthesis.

What does the central vacuole do?

Stores water, pigments, and toxins.

What is the difference between plant and animal cells regarding cell walls?

Plant cells have a cell wall; animal cells do not.

What is the difference between plant and animal cells regarding vacuoles?

Plant cells have a large central vacuole; animal cells have smaller, less prominent vacuoles.

What is the difference between plant and animal cells regarding centrioles?

Plant cells do not have centrioles; animal cells do.

What are the four major types of organic molecules?

Carbohydrates, lipids, proteins, nucleic acids.

What is a monomer?

An individual or simple building block.

What is the monomer of carbohydrates?

Monosaccharide.

What are the basic components of a triglyceride?

Glycerol and fatty acids.

What is the difference between saturated and unsaturated fatty acids?

Saturated fatty acids have no double bonds; unsaturated fatty acids have one or more double bonds.

What is the monomer of proteins?

Amino acid.

What bond joins amino acids?

Peptide bond.

What are the four levels of protein structure?

Primary, secondary, tertiary, quaternary.

What happens when a protein denatures?

It loses its structure and function.

What is the monomer of nucleic acids?

Nucleotide.

What are the components of a nucleotide?

Phosphate, pentose sugar, nitrogen-containing base.

What is the difference between DNA and RNA?

DNA contains deoxyribose, RNA contains ribose.

What are purines?

Adenine and Guanine.

What are pyrimidines?

Cytosine, Thymine, and Uracil.

What are the base-pairing rules in DNA?

A pairs with T, C pairs with G.

What is ATP?

Adenosine Triphosphate, the cell's energy currency.

What happens during ATP hydrolysis?

ATP is converted to ADP and energy is released.

What are the three parts of a nucleotide?

Sugar, phosphate group, nitrogenous base

What are the base-pairing rules for DNA?

Adenine pairs with Thymine, Cytosine pairs with Guanine

What are the purines?

Adenine and Guanine

What are the pyrimidines?

Cytosine, Thymine, and Uracil

What is ATP's main role in the cell?

To provide energy for cellular processes

What is the atomic number of an atom with 11 protons?

11

What element has 11 protons?

Sodium

What is the approximate atomic mass of an atom with 11 protons and 12 neutrons?

23

What happens when an atom gains two electrons?

It becomes an ion

Why does a cell benefit from having a high surface-area-to-volume ratio?

It allows for more efficient exchange of materials

Is a cell with a nucleus, mitochondria, ER, and Golgi apparatus prokaryotic or eukaryotic?

Eukaryotic

What is the complementary strand of a DNA sequence 5'-CGATTA-3'?

3'-GCTAAT-5'

What happens to a protein exposed to extreme heat?

It denatures and loses its shape, affecting its function

Why can phospholipids form a bilayer in water?

They have hydrophilic heads and hydrophobic tails

What is the definition of science?

The systematic study of the structure and behavior of the physical and natural world through observation and experiment

What are the seven characteristics of life?

Organization, energy acquisition, reproduction, response to stimuli, homeostasis, growth and development, adaptation

What is the order of levels of organization in biology?

Atom, molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere

What is the hierarchical classification of organisms?

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

What is a scientific hypothesis?

A proposed explanation for an unexplained phenomenon that is testable

What are the six major elements that make up 95% of organisms?

Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur

What is atomic mass?

The sum of protons and neutrons in an atom

What are isotopes?

Atoms of the same element with different numbers of neutrons

What is a radioactive isotope?

An isotope that decays over time

What is the half-life of Carbon-14?

5,730 years

What begins to decay after death?

¹⁴C

How many electrons can the first orbital contain?

2 electrons

How many electrons can later orbitals contain?

8 electrons

What are valence electrons?

Electrons in an atom's outer orbital that influence reactions and bonding.

What is associated with stability in an atom?

A full outer orbital.

What forms an ionic bond?

Electrons are transferred from one atom to another, creating ions with opposite charges.