Chapter 7

Question 1

Van Leeuwenhoek

Answer 1

A man from Holland who used a single-lens microscope to observe pond water and other things. The microscope revealed a fantastic world of tiny living organisms that seemed to be everywhere.

Question 2

Hooke

Answer 2

An English man who used an early compound microscope to look at a nonliving thin slice of cork, a plant material. He discovered what he called cells.

Question 3

Prokaryotes

Answer 3

Cells that do no enclose their DNA in nuclei

Question 4

Eukaryotes

Answer 4

Cells that enclose their DNA in their nuclei

Question 5

Cell Membrane

Answer 5

A thin flexible barrier surrounding the cell.

Question 6

Cell Wall

Answer 6

A strong supporting layer around the membrane.

Question 7

Nucleus

Answer 7

A large membrane-enclosed structure that contains genetic material in the form of DNA and controls many of cell’s activities.

Question 8

Cytoplasm

Answer 8

The portion of the cell outside of the nucleus.

Question 9

Nuclear Envelope

Answer 9

The double lipid bilayer membrane which surrounds the genetic material and nucleolus in eukaryotic cells.

Question 10

Nucleolus

Answer 10

A small dense region where the assembly of ribosomes begins.

Question 11

Chromatin

Answer 11

Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones.

Question 12

Chromosomes

Answer 12

Threadlike structures of DNA and protein that contains genetic information; in eukaryotes, chromosomes are found in the nucleus; in prokaryotes, they are found in the cytoplasm.

Question 13

Cytoskeleton

Answer 13

A network of protein filaments that give eukaryotic cells their shape and internal organization. It also helps transport material between different parts of the cell.

Question 14

Contractile Vacuoles

Answer 14

Large, saclike, membrane-enclosed structures that store materials like water, salts, proteins, and carbohydrates.

Question 15

Vescicles

Answer 15

A small organelle within a cell, consisting of fluid enclosed by a lipid bilayer membrane.

Question 16

Lipid Bilayer

Answer 16

Is what gives cell membranes a flexible structure that forms a strong barrier between the cell and it surroundings.

Question 17

Solute

Answer 17

The component in a solution that’s dissolved in the solvent.

Question 18

Solvent

Answer 18

The liquid in which a solute is dissolved to form a solution.

Question 19

Passive Transport

Answer 19

The movement of material across the cell membrane without using cellular energy.

Question 20

Active Transport

Answer 20

The movement of materials against a concentration difference. Active transport require energy.

Question 21

Diffusion

Answer 21

When molecules move from an area of higher concentration to an area of lower concentration.

Question 22

Equilibrium

Answer 22

When the concentration of the solute is the same throughout the solution.

Question 23

Facilitated Diffusion

Answer 23

When certain molecules cross the membrane through specific proteins channels found in the membrane.

Question 24

Osmosis

Answer 24

The diffusion of water through a selectively permeable membrane.

Question 25

Isotonic

Answer 25

When the concentration of the solutions are the same on both sides of the membrane.

Question 26

Hypertonic

Answer 26

The side of the cell with the higher concentration (above strength).

Question 27

Hypotonic

Answer 27

The side of the cell with the lower concentration (below strength).

Question 28

Osmotic Pressure

Answer 28

The pressure osmosis exerts on the hypertonic side of a selectively permeable membrane.

Question 29

Endocytosis

Answer 29

Taking materials into the cell by the means of infolding, or pockets, of the cell membrane.

Question 30

Phagocytosis

Answer 30

Large particles taken into the cell.

Question 31

Pinocytosis

Answer 31

Taking up liquid from their environment.

Question 32

Exocytosis

Answer 32

Vesicles fusing with the cell membrane.

Question 33

Unicellular

Answer 33

One-celled organisms.

Question 34

Multicellular

Answer 34

Organisms made up of many cells.

Question 35

Cell Specialization

Answer 35

The cell performing a specific function for a larger organ or tissue.

Question 36

Organ

Answer 36

Group of tissue working together.

Question 37

Organ System

Answer 37

Group of organs working together to perform a specific function.

Question 38

Receptor

Answer 38

A protein molecule usually found embedded within the plasma membrane surface of a cell that receives chemical signals from outside the cell.

Question 39

Cell Theory

Answer 39

Cells are the basic units of structure and function in living things, All living things are composed of cells, and new cells are produced from existing cells.