Biology Exam #1

A suggested and testable explanation for an event is called a

HYPOTHESIS

Concept supported by a broad range of observations, experiments, and data is called

SCIENTIFIC THEORY

Put the following organization levels in order from simple to complex:

atom, molecule, cell, tissue, organ, organism

State the processes of scientific method in logical order:

OBSERVATION, QUESTION, HYPOTHESIS, PREDICTION, EXPERIMENT, RESULT, CONCLUSION

The six most common elements in living things are

O, C, N, H, P, S

The smallest units of an element is

ATOM

The atomic number is the number of

PROTONS

The nucleus of an atom is made of

PROTON & NEUTRON

Isotopes of an element contain the same number of (1) ____

but a different number of

(2) ____ in the nucleus

1) PROTONS

2) NEUTRONS

If an atom’s atomic mass is 20, its atomic number is 9, it should have ___ neutrons, and ____ electrons

11 neutrons and 9 electrons

Which electron shell has the lowest energy level?

FIRST

If an atom’s atomic number is 8, how many electrons are in the outer most shell?

Is this atom reactive?

6

YES

Define compound

CONTAIN 2 OR MORE ELEMENTS

The chemical bond formed by equal or unequal sharing electrons between two atoms is called

COVELENT BOND

The attraction between water molecules is ____ bond

HYDROGEN

When an atom loses electrons, it turns into a (1) ____; when it gains electrons, it turns into an (2)_____; The attraction between these two ions is the (3)_____ bond.

1) CATION

2) ANION

3) IONIC

Match the molecules the chemical bond within them:

A) ionic bond B) polar covalent bond C) nonpolar covalent bond
H2O, KCl, O2, CO2, NaCl

H2O - POLAR COVALENT BOND

KCI - IONIC BOND

O2 - NONPOLAR COVALENT BOND

CO2 - NONPOLAR COVALENT BOND

NaCI - IONIC BOND

Water is a polar molecule and can form (1) _____ bonds with other water molecules. List the properties of water:

A.

B.

C.

D.

E.

1) HYDROGEN

A. RESIST TEMP CHANGE
b. COHESIVE, ADHESIVE
c. SOLVENT FOR HYDROPHILIC MOLECULES
d. HIGH SURFACE TENSION
e. WATER IS DENSER THAN ICE

(1)______and (2)________cannot be used as buffer to regulate pH.

Label the following as weak acid, weak base, strong acid, or strong base.

sodium hydroxide (NaOH) , ammonia (NH3), carbonic acid (H2CO3), hydrochloric acid (HCl)

1) STRONG ACID

2) STRONG BASE

sodium hydroxide (NaOH) STRONG BASE, ammonia (NH3) WEAK BASE,
carbonic acid (H2CO3) WEAK ACID, hydrochloric acid (HCl) STRONG ACID

When an acid is neutralized with a base (1)____ and (2)_____ are produced.

1) SALT

2) WATER

The pH scale is from (1)_____ to _____.

Is a pH 8 solution acidic, alkaline, or neutral? (2) _____

1) 0 TO 14

2) ALKALINE

All organic compounds contain atoms ______ and ______

C AND H

Explain why C is important for forming organic macromolecules

FORM COVELENT BONDS WITH UP TO 4 DIFFERENT ATOMS

What are the three elements found in all carbohydrates?

C, H, AND O

1. List the monosaccharides that contain carbons:

2. List the monosaccharides that contain 6 carbons:

3. List the disaccharides _

4. List the polysaccharides that are made of glucose:

1. RIBOSE, DEOXYRIBOSE

2. GLUCOSE, FRUCTOSE, GALACTOSE

3. MALTOSE, SUCROSE, LACTOSE

4. STARCH, GLYCOGEN , CELLULOSE

Lipids include the following
a. Triglyceride: made of one _____ and three _____
b. Steroid: has _______ fused carbon rings
c. Phospholipid: made of one ______, two ________, and one _____

A. GLYCEROL AND FATTY ACIDS

B. 4

C. GLYCEROL, FATTY ACID, PHOSPHATE GROUP

In unsaturated fatty acid, some carbon atoms only bind to ____ hydrogen.

1

A protein is a polymer of (1)____. There are (2)____ of them in living things, (3)____ of them are essential for adult humans

1) AMINO ACIDS

2) 20

3) 8

There are two forms of secondary structures of protein:

ALPHA HELIX & BETA SHEET

When a protein loses its function due to disruption of active sites, protein is _______.

DENATURED

List the nucleic acids: (1)____, (2)_____. They are polymers of (3) ______

1) DNA

2) RNA

3) NUCLEOTIDES

A nucleotide is made of a_____, a______, and a____

PHOSPHATE GROUP, PENTOSE SUGAR, N-CONTAINING BASE

The pentose sugar for DNA is _____, and for RNA is ___

DNA IS DEOXYRIBOSE

RNA IS RIBOSE

The N-containing base U can only be found in

RNA

In a DNA molecule A pairs with (1)___T, and G pairs with (2)___. The pairs are stabilized by ______ bonds

1. A PAIRS WITH T

2. G PAIRS WITH C

3. HYDROGEN BONDS

ATP is a nucleotide made of the base (1)___, the pentose sugar (2)____, and three (3)____ The terminal P bond is a (4)______ bond

1. A

2. RIBOSE

3. THREE PHOSPHATE

4. HIGH-ENERGY BOND

What is the smallest unit of life?

CELL

Eukaryotic cell has true nucleus, whereas prokaryotic cell has ___that is not enclosed by nuclear envelope.

NUCLEOID

The size of metabolically active cells is ____ because large surface area is needed for the exchange of materials

SMALL

Mitochondrion’s major function is to produce

ATP

Ribosomes are for making (1)____. Their large and small subunits are assembled in
(2) ____. They can attach to (3) _____ giving it the rough appearance

1. PROTIENS

2. NUCLEOUS

3. ROUGHER

The function of ______is to degrade unneeded substances

LYSOSOME

(1)___ is a membranous organelle. It uses its (2)___ face to receive vesicles and
(3) ___ face to deliver vesicles. It’s major function is to sort and pack proteins

1. GOLGI APPARATUS

2. CIS

3. TRANS

Define endomembrane system. ________

List its components. ____

1. CELLULAR STRUCTURES THAT ARE PHYSICALLY OR FUNCTIONALLY RELATED

2. NUCLEAR ENVELOPE, ER, VESICLE, GOLGI APPARATUS, LYSOSOME, PLASMA MEMBRANE

Peroxisome’s name comes from its unique product

H2O2

The three components of cytoskeleton are (1)____, (2)______, (3)_____.

Flagellum, centriole, and spindle fiber are all made of _____.

1. MICOGILAMENT

2. INTERMEDIATE FILAMENT

3. MICROTUBULE

all made up of: MICROTUBULE

ell nucleus is enclosed by a porous (1)_____. Inside the nucleus are
(2)______, the association of DNA with proteins

1. NUCLEAR ENVELOPE

2. NUCLEOLUS

Proteins that speed up reactions by decreasing the activation energy are called

ENZYMES

Plasma membrane is mainly made of two layers of (1)____ with their (2)_____ facing each other. Other molecules found in the membrane include (3)____ that can act as channels and (4) ____ that can stiffen and strengthen the membrane.

1. PHOSPHOLIPIDS

2. HYDROPHOBIC TAILS

3. INTEGRAL PROTEINS

4. CHOLESTEROL

The three types of intercellular junctions for animal cells are:

A. : to seal

B. to anchor

C: to allow passage from cell to cell

a. TIGHT JUNCTION : to seal
b. DESMOSOME: to anchor
c. GAP JUNCTION: to allow passage from cell to cell

Plant cells use ______ as intercellular communication

PLASMODESMATA

Compare plant cells to animal cells and list cellular structures that are unique to plants and structures that are missing in plants.

Unique to plants: CELL WALL, CHLOROPLAST, CENTRAL VACUOLE,
Missing: LYSOSOME, CENTRIOLE

Plant cell wall is mainly made of

CELLULOSE

Only _____ substances such as O2, CO2, and lipids can cross plasma membrane through simple diffusion.

HYDROPHOBIC

Transportation such as active transport, endocytosis, exocytosis requires ___

ATP

Cell internalizes solid particles through _____ and liquid through _____.

PHAGOCYTOSIS AND PINOCYTOSIS

A cell will (1)_____in a hypertonic solution, (2) ____ in a hypotonic solution such as
water, and (3)_____ in a isotonic solution such as normal saline

1. SHRINK

2. SWELL AND LYSE

3. NOT CHANGE