Bio Chapter 1,2,4 practice exam

What two observations did Charles Darwin make, and what were the two inferences he drew from those observations?

1. decendents from modification 2. natural selection is a mechinism for evolution

How many more hydrogen ions does a solution at pH 2 have than a solution at pH 4?

100 times more

What is the mass number of an atom with 14 protons, 13 neutrons, and 13 electrons?

27

For an atom to have a full valence shell, with the exception of the first shell, how many electrons should it have?

8 6 4 2

How many elements exist in nature?

92

We discussed three subatomic particles. Match the subatomic particle to its description.

Proton This subatomic particle equals the atomic number of an element. This subatomic particle has a net positive charge. Electron This subatomic particle orbits the nucleus and participates in chemical bonds. This subatomic particle has a net negative charge. Neutron A change in number in this subatomic particle creates isotopes. This subatomic particle is electrically neutral.

In the following chemical reaction (photosynthesis), what are the reactants and products? 6CO2 + 6H2O ----> C6H12O6 + 6O2

Reactants: 6CO2 + 6H2O; Products: C6H12O6 + 6O2

match terms with right definition

Resolution The ability of an instrument to show two close objects as separate. Magnification The increase in an object's image size compared with its actual size.

Describe the difference between SEMs and TEMs.

SEMS studied the archeteture cell structure while TEMS studied the internal cell structure

The outermost electron shell is called the ____________ __________.

Valence Shell

___________ is the tendency of two kinds of molecules to stick together.

adhesion

population

all alligators living in the wetlands

define cell theory

all living things are composed of cells and all cells come from cells

community

all organims in the wetlands of florida everglades

organism

an individual american alligator

A(n) _________ is the smallest unit of matter that still retains the properties of an element.

atom

________ is the scientific study of life.

biology

organ

brain

Define taxonomy, and list the hierarchy of classification.

branch of biology that names species, classifies species as genuis family order class phylum kingdom

In an ionic bond, when an electron is lost, a positive charge results, leaving us with a(n)____________ . When an electron is gained, a negative charge results, leaving us with a(n) ___________ .

cation anion

____________ is the tendency of molecules of the same kind to stick together.

cohesion

NaCl (sodium chloride) is a substance consisting of two elements in a fixed ratio. This is an example of a ______________.

compound

In a __________ ________, two atoms each with an unpaired electron in its outer shell, actually share a pair of electrons.

covalent bond

What is the difference between polar covalent bonds and non-polar covalent bonds?

covalent bond Water has atoms with different electronegativities non-polar covalent -In molecules of only one element, the pull toward each atom is equal, because each atom has the same electronegativity

biosphere

earth

A(n) _____________ ________________ is used to view the ultra structure of cells and uses a beam of electrons instead of light.

electron microscope

___________ ____________ occurs when molecules with the greatest amount of energy leave the surface. An example in humans is sweating.

evaporated cooling

Define evolution and natural selection.

evolution is the process of change over time natural selection is the mechunism for evolution

T/F Cells consist of about 90% water.

false

T/F Deductive reasoning makes generalizations based on collecting and analyzing a large number of specific observations.

false

T/F In a molecule of oxygen, the two oxygens have 6 electrons each in their outermost shell. This molecule of oxygen (O2) is held together by a triple covalent bond.

false

T/F Prokaryotic cells contain a nucleus and were the first to evolve.

false

T/F Thermal energy is measures the intensity of heat.

false

T/F When water freezes, hydrogen bonds are broken. In these ice crystals, molecules are less densely packed than in liquid water, and therefore ice floats in liquid water.

false

ecosystem

florida everglades

When water cools, water molecules slow down, ______more hydrogen bonds , and _________ a considerable amount of heat is .

form released

_________________ are the unit of inheritance that transmits information from parents to offspring.

genes

If a solution is said to have a neutral pH, this means the solution has the same amount of _____ as it does _____ .

h+ OH-

Through the unaided human eye, which of following can we see?

human egg cell

A __________ is a proposed explanation for a set of observations.

hypothesis

A(n) _________ is an atom or molecule with an electrical charge resulting from the gain or loss of electrons.

ion

Elements who have the same number of protons but different number of neutrons are called _______________.

isotopes molecules electrons compounds

Explain the what is meant by the terms producer, consumer, and decomposer in biological terms.

producer - provides food consumer - eats plants and other animals decomposer - acts as the recyclable and breaks down the complex chemicals into simpler chemicals

Two types of data that are frequently collected in scientific investigations are

qualitative and quantitative

To form hydrogen bonds, heat is _________.

released

If we add a teaspoon of table salt to a glass of water, we know it will dissolve. Here, water is the ______ and the table salt is the ______ . This is an example of a(n) _______ solution.

solvent solute aqueous

Explain what electronegativity is. You may use H2O to help explain if needed.

the attraction (pull) for shared electrons

Iron is an example of a ________ __________. Iron is essential to life, but is only found in minute quantities and must come from our diets.

trace element

T/F Atoms whose outermost shells are not full tend to interact with other atoms in ways that enable to complete their valence shell.

true

T/F Eukaryotic cells are subdivided by membranes into various functional compartments, called organelles.

true

molecule

DNA

The diversity of life arises from differences in __________ _______________.

DNA sequences

When discussing pH, in liquid water, a small percentage of water molecules break apart into hydrogen ions(H+) and hydroxide ions(OH-).

Acid -Donates hydrogen ions to a solution, therefore has a higher concentration of hydrogen ions. Base - Reduces hydrogen ion concentration of a solution. This is done by either accepting the hydrogen ions or by donating hydroxide ions. Buffer- Minimizes the changes in pH. This is done by donating or accepting hydrogen ions whenever needed.

The diversity of life can be arranged into three higher levels called domains. Match the domain to the best description of that domain.

Bacteria the most diverse and widespread prokaryotes Archaea prokaryotes that often live in Earth's extreme environments Eukarya have eukaryotic cells and include single-celled and multi-cellular organisms

The hydrogen bond is one of the most important types of weak bonds. Describe hydrogen bonds using H2O as an example.

Each hydrogen atom of a water molecule can form a hydrogen bond with a nearby partially negative oxygen atom of another water molecule. The negative (oxygen) pole of a water molecule can form hydrogen bonds to two hydrogen atoms.Thus, each H2O molecule can hydrogen-bond to as many as four partners

The first microscopes were _______________ __________________. In these microscopes, a visible light passes through a specimen, then through the glass lens, and finally is projected into the viewer's eye. You Answered

light microscopes

Living organisms are composed of _____________, which is anything that occupies space and has mass.

matter

organ system

nervous system

tissue

nervous tissue

cell

neurons

Organelle

nucleus

List the properties of life

order reproduction growth and development energy processing response to environment regulation evolutionary adoption

What four elements make up approximately 96% of the weight of most living organisms?

oxygen, hydrogen, carbon, and nitrogen