Quiz 2 Chap 4&5

Question 1

important figures in magnifying technology and what they created

Answer 1

Robert Hooke - early compound scope (magnifying glass)

Antonie van Leeuwenhoek - first dissecting microscope

Question 2

3 components of Cell Theory

Answer 2

1. all living organisms are made of cells
2. cells are the basic units of life
3. all cells come from pre-existing cells that have multiplied

Question 3

types of prokaryotic cells

Answer 3

bacteria and archaea

Question 4

types of eukaryotic cells

Answer 4

protists, fungi, plants, animals

Question 5

basic features of all cells

Answer 5

• plasma membrane with semifluid cytosol
• chromosomes (genes)
• ribosomes (make proteins)

Question 6

features of prokaryotic cells

Answer 6

• no nucleus
• DNA in unbound region (nucleoid)
• no membrane-bound organelles
• cytoplasm bound by plasma membrane

Question 7

features of eukaryotic cells

Answer 7

• membrane-bound nucleus (DNA) and organelles
• cytoplasm between plasma membrane and nucleus
• much larger than prokaryotic cells

Question 8

challenges all eukaryotic cells experience

Answer 8

• nutrition
• excretion
• energy
• interaction with environment
• reproduction

Question 9

what limits cell size?

Answer 9

SA/volume ratio

• as surface area increases by n squared, volume increases by n cubed
• small cells have a greater surface area relative to volume

Question 10

difference between plant and animal cells

Answer 10

animals: just semifluid membrane
plants: cell membrane and wall, more rigid
- chloroplasts
- large central vacuole

Question 11

endomembrane system

Answer 11

complex and dynamic compartmental cell organization

• regulates protein traffic
• performs metabolic functions
• components either continuous or connected via transfer by vesicles

Question 12

parts of the endomembrane system

Answer 12

plasma membrane
nuclear envelope
endoplasmic reticulum
golgi apparatus
lysosomes
vacuoles

Question 13

plasma membrane

Answer 13

selective barrier to cell allowing for the passage of oxygen and nutrients

• basic structure is a phospholipid bilayer
• proteins allow for membrane transport, often active

Question 14

nucleus

Answer 14

• largest organelle, most of cell’s DNA

- shape maintained by nuclear lamina

Question 15

nuclear envelope

Answer 15

double membrane around nucleus (2 bilayers)

- pores regulate entry and exit of materials from the nucleus

Question 16

chromatin

Answer 16

genetic material in nucleus (DNA and proteins), condenses into chromosomes during prophase I

Question 17

nucleolus

Answer 17

site of ribosomal RNA synthesis

Question 18

endoplasmic reticulum

Answer 18

more than 50% of membrane in cell, continuous with nuclear envelope

Question 19

smooth ER

Answer 19

no ribosomes

• synthesizes lipids
• metabolizes carbs
• detoxifies posions
• stores calcium

Question 20

rough ER

Answer 20

bound ribosomes on surface

• secretes glycoproteins (proteins bound to carbs covalently)
• distributes transport vesicles
• membrane factory for cell

Question 21

golgi apparatus STRUCTURE and function

Answer 21

flattened membrane sacs “cisternae”

• modifies ER products and sorts material into transport vesicle
• manufactures certain macromolecules

Question 22

lysosomes

Answer 22

digestive compartments
- membranous sac of hydrolytic enzymes that digest
macromolecules (hydrolize proteins, fats,
polysaccharaides, and nucleus acids)
- conduct autophagy – recycle the cell’s own
organelles and macromolecules

Question 23

phagocytosis

Answer 23

(when cells absorb bacteria/other material): lysosomes fuse with food vacuole to digest molecules

Question 24

types and functions of vacuoles

Answer 24

food vacuoles (animals) -- break down macromolecules
contractile vacuoles (protists) -- pump excess water out of cells to help movement
central vacuoles (plants) -- hold organic compounds and water

Question 25

structure and functions of cytoskeleton

Answer 25

network of fibers (actin, myosin, dyenin) in cytoplasm - organizes cell shape, structure, and activities - anchors organelles - interacts with motor proteins - aligns chromosomes during cell division

Question 26

importance of mitochondria structure

Answer 26

double membrane, smooth outer and folded inner (cristae) - not connected to endomembrane system - increases SA for ATP synthesis - inner membrane separates intermembrane space and matrix * some steps of respiration catalyzed in matrix

Question 27

mitochondria function

Answer 27

change energy from one form to another | - cellular respiration, generates ATP

Question 28

metabolism

Answer 28

all of organism's chemical reactions, emergent properties arise from interactions between molecules within cell

Question 29

metabolic pathway

Answer 29

linked series of chemical reactions - begins with a specific molecule and ends with a product - each step catalyzed by a specific enzyme

Question 30

anabolic vs catabolic pathways

Answer 30

anabolic - build large molecules (i.e. protein synthesis) | catabolic - releases energy by breaking down complex molecules (respiration)

Question 31

ATP structure and what is it

Answer 31

cell's energy shuttle | - made of ribose (sugar), adenine (nitrogenous base), and 3 phosphate groups

Question 32

how does ATP function in the cell

Answer 32

- energy released when phosphate bonds broken by hydrolysis | - ATP regenerated by an addition of a phosphate group to ADP

Question 33

phosphorylation

Answer 33

chemical addition of a phosphate group - phosphorylation cascade of proteins (signal transduction) - oxidative phosphorylation of ATP (cellular respiration)

Question 34

enzymes

Answer 34

catalytic proteins that speed up reactions by lowering activation energy

Question 35

catalyst

Answer 35

chemical agent that speeds up a reaction without being consumed

Question 36

activation energy

Answer 36

initial energy needed to start a chemical reaction, often supplied as heat from surroundings ****enzymes lower activation energy

Question 37

aerobic vs anaerobic respiration

Answer 37

aerobic: consumes organic molecules and O2, yields ATP anaerobic: consumes compounds other than O2

Question 38

what is the fuel for respiration?

Answer 38

primarily glucose, but carbs, fats, and proteins can all power it

Question 39

redox reactions

Answer 39

chemical reactions that transfer electrons between reactants | - release energy used to synthesize ATP

Question 40

oxidation vs reduction

Answer 40

oxidation - substance loses electrons, is oxidized, is reducing agent reduction - substance gains electrons, is reduced, is oxidizing agent

Question 41

what is oxidized during cellular respiration? what is reduced?

Answer 41

- fuel (glucose) is oxidized - carriers like NADH are temporarily reduced, then oxidized in ETC - O2 is reduced (at the end of ETC to form H2O)

Question 42

how do electrons transfer energy in respiration?

Answer 42

- electrons from organic compounds first transferred to NAD+ to make NADH and also to coenzyme A - each NADH represents stored energy to make ATP - NADH "electron carriers" donate electrons to compounds during the Electron Transport Chain * in ETC, O2 pulls electrons down the chain yielding energy for ATP in a series of redox reactions

Question 43

4 stages of respiration

Answer 43

glycolysis (glucose --> pyruvate) pyruvate oxidation citric acid cycle (completes glucose breakdown) oxidative phosphorylation (most of ATP synthesis)

Question 44

what stages does most ATP come from?

Answer 44

- 90% produced during oxidative phosphorylation, powered by redox reactions - rest produced during glycolysis and citric acid cycle by substrate-level phosphorylation

Question 45

glycolysis -- where, what goes in, what comes out

Answer 45

occurs in the cytoplasm; 2 major phases - energy investment phase (-2 ATP) *ATP used in phosphorylation of glucose, then split into 2 3- carbon molecules - energy payoff phase (+4 ATP, +2 NADH) * phosphorylation without ATP investment * net gain of +2 ATP and +2 NADH

Question 46

pyruvate oxidation -- where, what goes in, what comes out

Answer 46

occurs in matrix--pyruvate (3 carbon) binds with coenzyme A to become Acetyl CoA

Question 47

citric acid cycle -- where, what goes in, what comes out

Answer 47

oxidizes pyruvate within mitochondrial matrix; 8 steps each catalyzed by a specific enzyme ***begins with Acetyl CoA, yields 1 ATP, 3 NADH, and 1 FADH2 per turn - acetyl group of Acetyl CoA joins the cycle by binding with oxaloacetate to become citrate - next 7 steps decompose citrate back to oxaloacetate (making a cycle) - NADH and FADH2 that are produced by the cycle relay electrons from pyruvate to the ETC