Unit 4 Cell structure and transport

Question 1

cell theory

Answer 1

All life is composed of at least one cell
Cells are the basic units of living organisms. Structures (organelles) that compose cells are not considered alive
Cells develop only from pre-existing cells

Question 2

Prokaryote

Answer 2

Bacteria and Archae are prokaryotes
Lack a nucleus or membrane-bound organelles

Question 3

eukaryote

Answer 3

All forms of life with the exception of Bacteria and Archae
Contain a nucleus and membrane bound organelles

Question 4

endosymbiotic theory

Answer 4

mitochondria and chlorplasts used to be their own prokaryotic microbe before; may have combined with eukaryotic cells; this is thought because mitochondria and chloroplasts have their own DNA separate from the organisms

Question 5

Plant cells vs animal cells

Answer 5

Plant: chloroplasts, cell wall, central vacuole
Animal: centriole, cilia and flagellum

Question 6

cell wall

Answer 6

only in plant cells; nonliving and helps protect and support the cell; made of cellulose and it is semipermeable

Question 7

cell membrane

Answer 7

controls what comes in and out of the cell; prevents harmful materials from entering the cell

Question 8

nucleus

Answer 8

controls all of the cells activities and stores DNA

Question 9

nucleolus

Answer 9

small organelle inside the nucleus that makes ribosomes

Question 10

nuclear envelope

Answer 10

the membrane that surronds the nucleus

Question 11

chromatin

Answer 11

thin strands in the nucleus that contain genetic material

Question 12

cytoplasm/cytosol

Answer 12

the region on the inside of the cell; gelatinous fluid

Question 13

mitochondria

Answer 13

the “powerhouse” of the cell; they make energy that the cells can use; has its own unique DNA

Question 14

smooth endoplasmic reticulum

Answer 14

synthesize lipids like cholesterol and fats and metabolize carbs

Question 15

rough endoplasmic reticulum

Answer 15

primary site of protein synthesis; once protein synthesis is complete it folds and modifies the proteins; ribosomes attach to its surface to help in synthesizing proteins

Question 16

Golgi Apparatus

Answer 16

Modifies, sorts, and packages proteins and lipids for storage or transport out of the cell

Question 17

lysosomes

Answer 17

Contains digestive enzymes to break down waste material, old cell parts, and foreign invaders

Question 18

centriole

Answer 18

Involved in cell division (mitosis)
Organize the microtubules of the cytoskeleton

Question 19

centrosome

Answer 19

an organelle that consists of centrioles;

Question 20

vacuole

Answer 20

the storage area of cells; they store food and materials the cell needs; plants usually have one large vacuole and in animal cells they are smaller and less prominent

Question 21

vesicle

Answer 21

a sac that is used to transport materials in and out of the cell (endocytosis and exocytosis)

Question 22

phospholipid bilayer

Answer 22

this is what makes up the cell membranes in eukaryotes; composed of a hydrophilic head that faces toward the extracellular fluid; hydrophobic tail lines the inside of the bilayer

Question 23

passive transport

Answer 23

doesn’t require energy to move substances across the cell membrane; moves with the concentration gradient (high concentration to low concentration);

Question 24

diffusion

Answer 24

a method of passive transport; small and non-polar molecules; materials can just move across the membrane with no assistance

Question 25

facilitated diffusion

Answer 25

molecules need a transport protein to help them go through the membrane; transports larger molecules;

Question 26

osmosis

Answer 26

passive transport; the transport of water molecules

Question 27

concentration gradient

Answer 27

The difference in concentration from inside a cell to outside of a cell Substances move down the concentration gradient from high to low

Question 28

active transport

Answer 28

it requires energy; moves agaisnt the concentration gradient (low concentration to a high concentration); they use carrier proteins to carry materials

Question 29

endocytosis

Answer 29

method of active transport; a cell takes in substances from its surrounding environment by engulfing them within a small pocket of the cell membrane, which then pinches off to form a vesicle inside the cell; materials float around in the cell within a vesicle

Question 30

exocytosis

Answer 30

a cellular process where a cell releases substances stored within vesicles by fusing the vesicle membrane with the cell membrane,

Question 31

hypotonic

Answer 31

The concentration of solutes is LOWER OUTSIDE of the cell(extracellular fluid/environment) then inside the cell (cytoplasm)

Question 32

cytolysis

Answer 32

when there is an influx of water into the cell which causes it to burt

Question 33

hypertonic

Answer 33

The concentration of solutes is HIGHER OUTSIDE of the cell(extracellular fluid/environment) then inside the cell (cytoplasm)

Question 34

plasmolysis

Answer 34

when there is a shortage of water in the cell causing it to shrivel up

Question 35

turgor pressure

Answer 35

only in plant cells; the force against a cell wall from the influx of water; a high turgor pressure makes the plant look healthy