Ch 4 Cell Theory and Organelles

Question 1

what makes a cell a cell?

Answer 1

barrier, organelles, energy transfer, proteins, DNA

Question 2

plasma membrane

Answer 2

fluid mixture of equal parts lipid and protein by weight. regulates movement of MOST substances in and out of cell, contains phospholipids, cholesterols, and glycoproteins

Question 3

phospholipid bilayer

Answer 3

polar hydrophilic heads, nonpolar hydrophobic tails, ensures cytosol remains inside cell and interstitium outside

Question 4

membrane cholesterol

Answer 4

support

Question 5

membrane glycoproteins

Answer 5

maintain extracellular matrix

Question 6

membrane proteins

Answer 6

half of plasma membrane by weight, float and move in fluid bilayer, perform most membrane functions

Question 7

what are the six membrane proteins

Answer 7

transport, cell surface receptors, identify markers, enzymes, anchoring sites, cell adhesion

Question 8

transport proteins

Answer 8

regulate movement of substances across membrane

Question 9

cell surface receptors

Answer 9

bind molecules call ligands

Question 10

identify markers

Answer 10

distinguish healthy cells from cells to be destroyed

Question 11

enzymes

Answer 11

catabolize chemical reactions, could be internal or external

Question 12

anchoring sites

Answer 12

secure cytoskeleton to plasma membrane

Question 12

cell adhesion

Answer 12

perform cell to cell attachments

Question 13

ligands

Answer 13

molecules that bind to macromolecules, ie a neurotransmitter released from a nerve cell that binds to the cell surface receptor of a muscle cell

Question 14

a cell is only a cell if…

Answer 14

…plasma membrane is intact and functioning

Question 15

cytoplasm

Answer 15

cellular components between plasma membrane and nucleus. includes cytosol, organelles, and inclusions

Question 16

cytosol

Answer 16

viscous fluid of the cytoplasm, high water content, contains dissolved macromolecules and ions

Question 17

organelles

Answer 17

complex organized structures within cells, unique shapes and functions

Question 18

membrane bound

Answer 18

organelles enclosed by a membrane

Question 19

non-membrane bound

Answer 19

composed of protein

Question 20

nucleus

Answer 20

contains DNA instructions for building proteins, controls functions of cell
membrane bound

Question 21

ribosomes

Answer 21

read genetic information coming from nucleus and translates it
non-membrane bound

Question 22

rough endoplasmic reticulum

Answer 22

ribosomes attached, protein synthesis
membrane bound

Question 23

smooth endoplasmic reticulum

Answer 23

lipid synthesis (liver) steroid synthesis (testes) absorption and transport of fats (intestines) detoxification (liver) molecule breakdown (liver)
membrane bound

Question 24

golgi complex

Answer 24

logistics center: modifies proteins and lipids. vesicles move to membrane and contents expelled through exocytosis
membrane bound

Question 25

lysosome

Answer 25

vesicles containing digestive enzymes - acidic (phagocytosis)
membrane bound

Question 26

mitochondria

Answer 26

powerhouse of the cell. ATP production
membrane bound

Question 27

cytoskeleton

Answer 27

made of fibrous proteins
microfilaments - actin
intermediate filaments - high tension strength; tendons, filaments
microtubules - function in intercellular matrix
non-membrane bound

Question 28

centrioles

Answer 28

barrel shaped, base of cilia and flagella, important in mitosis
non-membrane bound