Chapter 4

Question 1

Cell Theory

Answer 1

Cells are fundamental units of life and function.

Question 2

Homeostasis

Answer 2

Maintenance of stable internal conditions in cells.

Question 3

Cytology

Answer 3

Study of cell structure and function.

Question 4

Sex Cells

Answer 4

Reproductive cells with one chromosome set.

Question 5

Somatic Cells

Answer 5

All body cells except reproductive cells.

Question 6

Cell Membrane

Answer 6

Barrier separating cytoplasm from extracellular fluid.

Question 7

Interstitial Fluid

Answer 7

Fluid between cells in tissues.

Question 8

Physical Isolation

Answer 8

Cell membrane forms barrier to protect contents.

Question 9

Selective Permeability

Answer 9

Regulates entry and exit of substances.

Question 10

Cellular Receptors

Answer 10

Proteins detecting environmental changes.

Question 11

Cytoskeleton

Answer 11

Structural proteins providing cell shape and strength.

Question 12

Microvilli

Answer 12

Projections increasing surface area for absorption.

Question 13

Centrioles

Answer 13

Assist in cell division by forming spindle apparatus.

Question 14

Cilia

Answer 14

Extensions moving fluids across cell surfaces.

Question 15

Ribosomes

Answer 15

Sites of protein synthesis in cells.

Question 16

Free Ribosomes

Answer 16

Ribosomes synthesizing proteins for cell use.

Question 17

Fixed Ribosomes

Answer 17

Ribosomes attached to ER for secretion.

Question 18

Proteasomes

Answer 18

Degrade damaged proteins into peptides.

Question 19

Endoplasmic Reticulum

Answer 19

Network of membranes for synthesis and transport.

Question 20

Smooth ER

Answer 20

Synthesizes lipids and carbohydrates, no ribosomes.

Question 21

Rough ER

Answer 21

Has ribosomes; synthesizes proteins and glycoproteins.

Question 22

Golgi Apparatus

Answer 22

Modifies and packages proteins for secretion.

Question 23

Lysosomes

Answer 23

Digestive vesicles breaking down waste materials.

Question 24

Peroxisomes

Answer 24

Break down fatty acids, producing hydrogen peroxide.

Question 25

Mitochondria

Answer 25

Powerhouses producing ATP through aerobic respiration.

Question 26

Nucleus

Answer 26

Control center containing DNA and genetic information.

Question 27

Nuclear Envelope

Answer 27

Double membrane surrounding the nucleus.

Question 28

Nucleoli

Answer 28

Sites of ribosomal RNA synthesis within nucleus.

Question 29

Nucleosomes

Answer 29

DNA coiling around histone proteins for structure.

Question 30

Genetic Code

Answer 30

Sequence of nitrogenous bases encoding protein instructions.

Question 31

Genes

Answer 31

Functional DNA units coding for proteins.

Question 32

Triplet Code

Answer 32

Three-base sequence representing one amino acid.

Question 33

Protein Synthesis

Answer 33

Process of creating proteins from RNA.

Question 34

Transcription

Answer 34

Conversion of DNA into RNA.

Question 35

Translation

Answer 35

Conversion of RNA into proteins.

Question 36

Permeability

Answer 36

Determines material movement across a membrane.

Question 37

Impermeable Membrane

Answer 37

Allows no materials to pass through.

Question 38

Freely Permeable Membrane

Answer 38

Allows all materials to pass through.

Question 39

Selectively Permeable Membrane

Answer 39

Allows some materials to pass, restricts others.

Question 40

Active Transport

Answer 40

Requires energy (ATP) to move substances.

Question 41

Passive Transport

Answer 41

No energy required for substance movement.

Question 42

Diffusion

Answer 42

Movement of molecules from high to low concentration.

Question 43

Concentration Gradient

Answer 43

Difference in solute concentration across a space.

Question 44

Simple Diffusion

Answer 44

Direct movement of lipid-soluble compounds.

Question 45

Channel-Mediated Diffusion

Answer 45

Movement of water-soluble compounds through channels.

Question 46

Osmosis

Answer 46

Diffusion of water across a membrane.

Question 47

Tonicity

Answer 47

Effect of solute concentration on cell volume.

Question 48

Isotonic Solution

Answer 48

No net movement of water in/out of a cell.

Question 49

Hypertonic Solution

Answer 49

Causes cell to lose water and shrink.

Question 50

Hypotonic Solution

Answer 50

Causes cell to gain water and potentially rupture.

Question 51

Carrier-Mediated Transport

Answer 51

Transport proteins move specific substances across membranes.

Question 52

Cotransport

Answer 52

Simultaneous transport of two substances in same direction.

Question 53

Countertransport

Answer 53

Transport of one substance in while another exits.

Question 54

Active Transport Proteins

Answer 54

Move ions against concentration gradients using ATP.

Question 55

Sodium-Potassium Exchange Pump

Answer 55

Moves 3 Na+ out and 2 K+ into cells.

Question 56

Vesicular Transport

Answer 56

Bulk transport of substances using vesicles.

Question 57

Endocytosis

Answer 57

Process of taking substances into the cell.

Question 58

Pinocytosis

Answer 58

Cell drinking; uptake of extracellular fluid.

Question 59

Phagocytosis

Answer 59

Cell eating; engulfing large particles.

Question 60

Exocytosis

Answer 60

Process of expelling substances from the cell.

Question 61

Cell Life Cycle

Answer 61

Sequence of events from one cell division to another.

Question 62

Interphase

Answer 62

Phase where cells spend most time working.

Question 63

Mitosis

Answer 63

Division of the nucleus into two nuclei.

Question 64

Prophase

Answer 64

First stage of mitosis; chromosomes condense.

Question 65

Metaphase

Answer 65

Chromosomes align at the metaphase plate.

Question 66

Anaphase

Answer 66

Chromosomes are pulled apart to opposite poles.

Question 67

Telophase

Answer 67

Nuclear membranes reform around separated chromosomes.

Question 68

Cytokinesis

Answer 68

Division of cytoplasm into two daughter cells.