Chapter 3 - Cell biology

Question 1

Lysosome

Answer 1

-Contains digestive enzymes
-Forms at Golgi
-Autophagy - breaks down organelles

Question 2

Glycocalyx

Answer 2

Combination of glucose and lipids (glycolipids) and proteins (glycoproteins) on outer membrane of plasma membrane

Question 3

Integral membrane proteins

Answer 3

-Extend deep into membranes, often from one surface to another
-Can form channels through

Question 4

Peripheral membrane proteins

Answer 4

-Attached to integral proteins at either the inner or outer surface of the lipid bilayer

Question 5

Marker molecules

Answer 5

-Glycoproteins or glycolipids
-Allow cells to identify each other or other molecules

Question 6

Transport proteins examples

Answer 6

-Channel proteins
-Carrier proteins
-ATP-powered pumps

Question 7

Transport protein specificity

Answer 7

-Single type of molecule
-Competition among similarly-shaped molecules
-Saturation - transport rate limited to number of available proteins

Question 8

Channel proteins

Answer 8

Leaky ion - always open
Gated ion - can be opened or closed by certain stimuli

Question 9

Carrier proteins

Answer 9

-AKA transporters
-Move ions from one side of membrane to the other
-Specific binding sites
-Protein changes shape to transport, then resumes original shape after

Question 10

Types of passive membrane transport

Answer 10

-Osmosis
-Diffusion
-Facilitated diffusion

Question 11

Viscosity

Answer 11

Measure of a fluid’s resistance to flow

Question 12

Aquaporins

Answer 12

Water channels

Question 13

Osmotic pressure

Answer 13

Force required to prevent water from moving across a membrane by osmosis

Question 14

Facilitated diffusion

Answer 14

-No ATP required
-Carrier or channel proteins
-Move manufactured proteins out, amino acids and glucose in

Question 15

Sodium potassium pump

Answer 15

-Move ions against concentration gradient to sustain electrical membrane potential
-Sodium out of cell, potassium in

Question 16

Secondary active transport

Answer 16

Uses potential energy in concentration gradient (established with primary active transport) to help move another substance

Question 17

Vesicular transport

Answer 17

-Requires ATP
-Endocytosis (phagocytosis and pinocytosis)
-Exocytosis

Question 18

Microtubules

Answer 18

-Hollow tubes made of tubulin protein
-Internal scaffold, transport, cell division

Question 19

Actin filaments/microfilaments

Answer 19

Structure, support for microvilli, contractility, movement

Question 20

Intermediate filaments

Answer 20

Mechanical strength

Question 21

Cytoplasmic inclusions

Answer 21

-Aggregates of chemical such as lipid droplets
-Melanin

Question 22

Nucleolus

Answer 22

Dense region where ribosomes are manufactured

Question 23

Cadherins

Answer 23

Proteins that attach cells to other cells

Question 24

Integrins

Answer 24

Proteins that attach cells to extracellular molecules

Question 25

Cisternae

Answer 25

Interior space of sacs and tubules that make up the ER

Question 26

Smooth ER

Answer 26

Makes lipids and carbohydrates

Question 27

Peroxisomes

Answer 27

-Contains enzymes to break down fatty acids and amino acids -Hydrogen peroxide is a by-product - also breaks this down

Question 28

Centrioles

Answer 28

-Located in centrosome (specialized zone near nucleus) -Center of microtubule formation -Organize spindle fibers (type of microtubule) during cell division

Question 29

Cilia

Answer 29

-Move materials over surface of cells -Contains microtubules -Dynein arms -Basal body

Question 30

Dynein arms

Answer 30

-Connect adjacent microtubules -Push microtubules past each other

Question 31

Basal body

Answer 31

-Modified centriole -Located at base of cilium

Question 32

Microvilli

Answer 32

-Extension of plasma membrane to increase surface area -Many per cell -Do not move

Question 33

Prophase

Answer 33

-Nuclear envelope disintegrates -Chromatin condenses -Spindles attach to kinetochore

Question 34

Metaphase

Answer 34

Chromosomes align at nuclear equator

Question 35

Anaphase

Answer 35

-Spindles separate the chromatids -Cytokinesis begins

Question 36

Telophase

Answer 36

-Chromosomes decondense -Nuclear envelope reforms -Cytokinesis continues

Question 37

Kinetochore

Answer 37

Protein structure that binds the centromere and provides a point of attachment for microtubules that will separate and move the chromatids during mitosis