Chapter 3 - Nutrients and Membrane Transport

Question 1

Nutrients

Answer 1

The substances in food that provide energy and structural materials

Question 2

Macronutrient

Answer 2

Nutrients that are required in large amounts (carbohydrates, proteins, water, and fats)

Question 3

Dehydration

Answer 3

A decrease below the body’s required water level

Question 4

Complex carbohydrates

Answer 4

Sugars that are composed of many subunits and arranged in branching chains

Question 5

Processed food

Answer 5

Food that has undergone extensive refinement and has been stripped of much of its nutritive value

Question 6

Whole foods

Answer 6

Foods that have not been stripped of their nutrition by processing

Question 7

Essential amino acids

Answer 7

Amino acids that your body cannot synthesize

Question 8

Complete proteins

Answer 8

Foods that contain all the amino acids your body needs

Question 9

Essential fatty acids

Answer 9

Fatty acids that cannot be synthesized by your body

Question 10

Saturated fat

Answer 10

Type of lipid rich in hydrogen and single bonds

Question 11

Unsaturated fats

Answer 11

Type of lipid containing many carbon-to-carbon double bonds, liquid at room temperature

Question 12

Polyunsaturated

Answer 12

Lipid that contains many unsaturated carbons

Question 13

Hydrogenation

Answer 13

Adding hydrogen gas under pressure to make liquid oils more solid

Question 14

Trams fat

Answer 14

Contains unsaturated fatty acids that have been hydrogenated, which changes the fat from a liquid to a solid at room temperature

Question 15

Micronutrients

Answer 15

Nutrients that are essential in small amounts

Question 16

Coenzymes

Answer 16

Molecules that help enzymes

Question 17

Mineral

Answer 17

Inorganic substances that do not contain carbon but are essential for many cell functions

Question 18

Vitamins

Answer 18

Organic substances supplied by food that often help with enzymic functions

Question 19

Antioxidants

Answer 19

Substances in food that prevent cells from damage caused by molecules that are generated by normal cell processes

Question 20

Free radicals

Answer 20

Highly reactive molecules with an incomplete electron shell

Question 21

Organelles

Answer 21

Individual structures within a cell that have specific and necessary functions

Question 22

Cytosol

Answer 22

Watery mix inside the cell that contains salt and enzymes

Question 23

Cytoplasm

Answer 23

Includes organelles and cytosol

Question 24

Plasma membrane

Answer 24

defines the outer boundary of each cell, isolates the cell’s contents from the environment, and serves as a barrier that determines which nutrients are allowed into and out of the cell

Question 25

Cell membrane

Answer 25

Encloses structures within the cell

Question 26

Semipermeable

Answer 26

Characteristic of cell membranes that only allows some substances to cross

Question 27

Phospholipid bilayer

Answer 27

The membrane that surrounds cells and organelles and is composed of two layers of phospholipids

Question 28

Fluid mosaic

Answer 28

The accepted model for how membranes are structured with proteins bobbing in a sea of phospholipids, allowing the composition of the membrane to change

Question 29

Cell wall

Answer 29

Tough but elastic structure surrounding plant and bacterial cell membrane

Question 30

Nucleus

Answer 30

Spherical cell structure that houses DNA; found in eukaryote

Question 31

Nuclear envelope

Answer 31

The double membrane enclosing the nucleus in eukaryotes, studded with nuclear pores that regulate traffic into and out of the nucleus

Question 32

Chromatin

Answer 32

Structure inside the nucleus that is composed of DNA and proteins

Question 33

Nucleolus

Answer 33

Structure inside the nucleus where ribosomes are synthesized

Question 34

Mitochondria

Answer 34

An energy-producing organelles surrounded by a double membrane (powerhouse of the cell)

Question 35

Chloroplasts

Answer 35

An organelle in plants that uses the sun’s energy to convert carbon dioxide and water into sugars

Question 36

Thylakoids

Answer 36

Flattened membranous sac located in the chloroplast stroma, stack to form grana

Question 37

Chrolophyll

Answer 37

Pigment molecules that reflect green light

Question 38

Lysosome

Answer 38

A membrane-enclosed sac of digestive enzymes that degrade proteins, carbohydrates, and fats

Question 39

Ribosomes

Answer 39

Organelles in which proteins are assembled

Question 40

Endoplasmic reticulum

Answer 40

A large network of membranes that begins at the nuclear envelope and extends into the cytoplasm of a eukaryotic cell

Question 41

Golgi apparatus

Answer 41

A stack of membranous sacs that receive, modify, sort, and send proteins from ER vesicles

Question 42

Centriole

Answer 42

A barrel-shaped rings composed of microtubules that anchor structures that help move chromosomes around when an animal cell divides

Question 43

Cytoskeleton

Answer 43

A framework made of protein fibers that gives shape and structural support to cells

Question 44

Central vacuole

Answer 44

Large fluid-filled organelles in plants that contain a variety of dissolved molecules, including sugars and pigments

Question 45

Diffusion

Answer 45

The movement of molecules from where they are in high concentration to where they are in low concentration

Question 46

Passive transport

Answer 46

When substances diffuse across the plasma membrane without requiring any energy input

Question 47

Facilitated diffusion

Answer 47

When molecules are transported across membranes by proteins embedded in the lipid bilayer without the input of energy

Question 48

Osmosis

Answer 48

The movement of water across a membrane (sometimes through aquaporins) from areas of high concentration to low

Question 49

Active transport

Answer 49

The transport that uses proteins, powered by ATP, to move substances up a concentration gradient

Question 50

Exocytosis

Answer 50

When a membrane-bound vesicle, carrying some substance, fuses with the plasma membrane and releases its contents into the exterior of the cell

Question 51

Endocytosis

Answer 51

When a substance is brought into the cell by a vesicle engulfing and pinching the plasma membrane inward