Exam 1

Question 1

General and unifying concepts that govern all study and research:

Answer 1

• The cell is the basic unit of life
• Genes (consisting of DNA/RNA) are the basic unit of heredity
• Evolution accounts for the untity and diversity seen among living organisms
• All organisms survive by consuming and transforming energy
• All organisms maintain a stable internal environment

Question 2

The scientific method

Answer 2

• Make an observation
• Ask a questin
• Form a hypothesis
• Make a prediction
• Experiment
• Report results

Question 3

Basic scence vs. Applied science

Answer 3

Basic science or “pure” science seeks to expand knowledge regardless of the short-term application of that
knowledge (knowledge for knowledge’s sake). It is not focused on developing a product or a service of
immediate public or commercial value Vs. Applied science or “technology,” which aims to use science to
solve real-world problems. In applied science, the problem is usually defined for the researcher.

Question 4

Inductive reasoning and Deductive reaoning

Answer 4

-Inductive reasoning is a form of logical thinking that uses related observations to arrive at a general
conclusion.

-Deductive reasoning is a form of logical thinking that uses a general principle or law to predict specific
results.

Question 5

Proporties of life

Answer 5

1. Order
2. sensitivity or respond to stimuli
3. Reproduction
4. Growth and Devlopment
5. Regulation
6. Homeostasis
7. Energy processing

Question 6

Levels of organization of living things

Answer 6

1. Celluar level
   - atoms, molecules, organelles, cells.
2. organismal level
   - Tisssues, organ, organ system.
3. Population level
   - Population community
4. Ecosystem
5. Biosphere

Question 7

Sturcute or the atom

Answer 7

Atoms consist of three basic particles:

protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).

Question 8

Atomic number and mass

Answer 8

Atoms of each element contain a characteristic number of protons and electrons. The number of protons determines an element’s atomic number, which scientists use to distinguish one
element from another. Atomic mass is the average mass of an element.

Question 9

Isotopes

Answer 9

Different forms of an element that have the same number of protons but a different number of neutrons

Question 10

Electron shell

Answer 10

a grouping of electrons surrounding the nucleus of an atom

Question 11

Valence shell

Answer 11

Electron in the outermost shell

Question 12

Ribosomal RNA

Answer 12

Ribosomal RNA In molecular biology, ribosomal ribonucleic acid (rRNA) is the RNA component of the ribosome, and is essential for protein synthesis in all living organisms.

Question 13

RNA

Answer 13

Ribonucleic acid (RNA) is a molecule similar to DNA. Unlike
DNA, RNA is single-stranded.

Question 14

Ions and ionic bonds

Answer 14

Ionic bond is a chemical bond that forms between two ions with opposite charger (cations and anions).

-Ion atom/ chemical group that does not contain equal number of protons and elctrons.

Cations are postive ions formed by an atom losing one or more electron

Anions are negative ions formed by an atom gaining one or more electrons

Question 15

Covelant bonds

Answer 15

Covelant bond type of strong bond formed between two atoms of the same/ different elements ; forms when electrons are shared between atoms.
-The more covenant bonds between two atoms, the stroger their connection.

Single covelant bond- A bond formed when two atoms share a pair of electrons

Double covelant bond- A bond in which two atoms share two pairs of electrons

Tripple covelnat bond- A bond formed by sharing three pairs of electrons

Question 16

Cell theory

Answer 16

1. All organisms are composed of cells
2. Cells are the smallest living things
3. Cells arise onlt through pre-existing cells

Question 17

Prokaryotic cells

Answer 17

Lacks a membrane-bound nucleus 
-gentic material is present in the nucleoid.
Two types of prokaryotes:
-archea
-bacteria

Question 18

Cell size

Answer 18

Cell size is limited.
- As a cell size increases, it takes longer for material to diffuse from the cell membrane to the interior of the cell.
Surface area-to-volume: as a cell increases in size, the volume increases 10x faster than the surface area

Question 19

Eukaryotic cells

Answer 19

• posses a membrane-bound nucleus
• are more complex than prokaryotic cells
• compartmentalize many celluar functions within organelles and the endomembrane system.
• posses a cytoskeleton for support and to maintain celluar structure.

Question 20

Nucleus

Answer 20

• nuclues region is for ribosome synthesis
• control center of the cell
• Linear chromosomes are DNA orgainzed with proteins to form chromatin
• surround by a nuclues envelope composed if 2 phospholid bilayers which is continuous with the endoplasmic reticulum
• nuclear pores allow substances to enter an md exit the nucleus

Question 21

Ribosomes

Answer 21

• Ribosomes are made up of a large subunit (top) and a small subunit (bottom)
• Site of protein synthesis in the cell (assemble amino acids into proteins)
• composed of ribosomal RNA and proteins
• found within the cytosol of the cytoplasm and attached to internal membranes

Question 22

Mitochondria

Answer 22

• present in all types of eukaryotic cells
• contain oxidative metabolism enzymes for transferring the energy within macromolecules to ATP
• surrounded by 2 membranes
• smooth outer membrane
• folde inner membrane with layers called cristae
• matrix is within the inner membrane
• intermembrane space is located between the two membranes
• contain their own DNA