CH03 - SUMMARY

Question 1

They are highly organized units containing organelles, which perform specific functions.

Answer 1

Cells

Question 2

contains genetic material

Answer 2

nucleus

Question 3

This is the living
material between the nucleus and the cell membrane

Answer 3

cytoplasm

Question 4

These are the basic unit of life

Answer 4

Cells

Question 5

Cells protect and support the body, as well as provide for cell __________, __________, and ______________.

Answer 5

metabolism, communication, and inheritance.

Question 6

This forms the outer boundary of the cell. It determines what enters and leaves the cell.

Answer 6

cell membrane

Question 7

The cell membrane is composed of a double layer of __________ molecules in which proteins float.

Answer 7

phospholipid

Question 8

__________ is the movement of a solute from an area of higher concentration to an area of lower concentration within a solvent. At equilibrium, the distribution of molecules is uniform.

Answer 8

Diffusion

Question 9

____________ is the concentration of a solute at one point in a solvent minus the concentration of that solute at another point in the solvent divided by the distance between the
points.

Answer 9

concentration gradient

Question 10

_____________ pass through the cell membrane readily by dissolving in the lipid portion of the membrane. Small molecules and ions can pass through membrane channels.

Answer 10

Lipid-soluble molecules

Question 11

This is the diffusion of water across a selectively permeable membrane.

Answer 11

Osmosis

Question 12

In a _________ solution, cells swell (and can undergo lysis)

Answer 12

hypotonic

Question 13

In an _______ solution, cells neither swell nor shrink

Answer 13

isotonic

Question 14

In a _______ solution, cells shrink and undergo crenation.

Answer 14

hypertonic

Question 15

______________ transport is the movement of a substance across a membrane by means of a carrier molecule. The substances transported tend to be large, water-soluble molecules or ions.

Answer 15

Carrier-mediated transport

Question 16

_______________ moves substances from a higher to a lower concentration and does not require energy in the form of ATP.

Answer 16

Facilitated Diffusion

Question 17

_________transport can move substances from a lower to a higher concentration and requires ATP.

Answer 17

Active transport

Question 18

______________ transport uses the energy of one substance moving down its concentration gradient to move another substance across the cell membrane.

Answer 18

Secondary active transport

Question 19

In ____________, both substances move in the same direction.

Answer 19

cotransport

Question 20

In ___________, they move in opposite directions

Answer 20

countertransport.

Question 21

______________ is the movement of materials into cells by the formation of a vesicle.

Answer 21

Endocytosis

Question 22

___________ is the movement of solid material into cells.

Answer 22

Phagocytosis

Question 23

_______________is similar to phagocytosis, except that the material ingested is much smaller and is in solution.

Answer 23

Pinocytosis

Question 24

_____________ is the secretion of materials from cells by vesicle formation.

Answer 24

Exocytosis

Question 25

_____________ consists of two separate membranes that form nuclear pores at many points on the surface of the nucleus.

Answer 25

nuclear envelope (nucleus)

Question 26

DNA and associated proteins are found inside the nucleus as __________

Answer 26

chromatin

Question 27

__________ consist of RNA and proteins and are the sites of ribosomal subunit assembly.

Answer 27

Nucleoli

Question 28

___________ are the sites of protein synthesis

Answer 28

Ribosomes

Question 29

A ribosome is composed of ______________

Answer 29

one large and one small subunit

Question 30

Rough ER is a major site of _________________

Answer 30

protein synthesis

Question 31

Smooth ER is a major site of ________________.

Answer 31

lipid synthesis

Question 32

____________is a series of closely packed membrane sacs that collect, modify, package, and distribute proteins and lipids produced by the ER.

Answer 32

Golgi apparatus

Question 33

__________________ are membrane-bound sacs that carry substances from the Golgi apparatus to the cell membrane, where the vesicle contents are released.

Answer 33

Secretory Vesicles

Question 34

membrane-bound sacs containing enzymes, ____________break down phagocytized material.

Answer 34

Lysosomes

Question 35

membrane-bound sacs containing enzymes, ____________ break down fatty acids, amino acids, and hydrogen peroxide

Answer 35

Peroxixomes

Question 36

the major sites for the production of ATP, which cells use as an energy source. Mitochondria carry out aerobic respiration (requires O2).

Answer 36

Mitochondria

Question 37

This supports the cytoplasm and organelles and is involved with cell movements.

Answer 37

Cytoskeleton

Question 38

The cytoskeleton is composed of _____________, ________________, _______________.

Answer 38

microtubules, microfilaments, intermediate filaments

Question 39

_________ are located in the centrosome, are made of microtubules. They facilitate chromosome movement during cell division.

Answer 39

Centrioles

Question 40

This helps move substances over the surface of cells.

Answer 40

Cilia

Question 41

are much longer than cilia and propel sperm cells.

Answer 41

Flagella

Question 42

Increase the surface area of cells and thus aid in absorption.

Answer 42

Microvilli

Question 43

During ___________, the sequence of nucleotides in DNA (a gene) determines the sequence of nucleotides in mRNA; the mRNA moves through the nuclear pores to ribosomes.

Answer 43

transcription

Question 44

During ___________, the sequence of codons in mRNA is used at ribosomes to produce proteins. Anticodons of tRNA bind to the codons of mRNA, and the amino acids carried by tRNA are joined to form a protein.

Answer 44

translation

Question 45

The ________ consists of a series of events that produce new cells for growth and for tissue repair.

Answer 45

cell cycle

Question 46

The two phases of the cell cycle are __________ and __________.

Answer 46

interphase cell division

Question 47

DNA replicates during _____________, the nondividing phase of the cell cycle.

Answer 47

interphase

Question 48

Cell division occurs through ___________, which is divided into four stages.

Answer 48

mitosis

Question 49

Phase: each chromosome consists of two chromatids joined at the centromere.

Answer 49

Prophase

Question 50

Phase: chromosomes align at the center of the cell.

Answer 50

Metaphase

Question 51

Phase: chromatids separate at the centromere and migrate to opposite poles.

Answer 51

Anaphase

Question 52

Phase: the two new nuclei assume their normal structure, and cell division is completed, producing two new daughter cells.

Answer 52

Telophase

Question 53

the process by which cells develop specialized structures and functions, results from the selective activation and inactivation of DNA sections.

Answer 53

Differentiation

Question 54

Is the programmed death of cells. This regulates the number of cells within various tissues of the body.

Answer 54

Apoptosis