Exam #1

Question 1

What are the 3 main types of tissues in plants?

Answer 1

dermal tissue, ground tissue, and vascular tissue

Question 2

Dermal Tissue

Answer 2

The outermost layer of a plant, provides protection and does water and gas exchange.

Question 3

Epidermis

Answer 3

outermost single layer of cells in the dermal tissue

Question 4

Trichomes

Answer 4

modified epidermal cells, for protection and water retention

Question 5

Stomata

Answer 5

two guard cells enclosing an aperture, regulate transpiration

Question 6

Ground tissue

Answer 6

internal tissues that make up the bulk of the plant (parenchyma, collenchyma, sclerenchyma)

Question 7

Parenchyma

Answer 7

thin cell walls, provide storage and photosynthesis

Question 8

Palisade Parenchyma

Answer 8

filled with chloroplasts, line the epidermal cells

Question 9

Spongy parenchyma

Answer 9

filled with chloroplasts, have a lot of intracellular space to allow for gas movement and exchange

Question 10

Collenchyma

Answer 10

perform metabolic processes, provide storage, transport, and mechanical strength

Question 11

Sclerenchyma

Answer 11

have a secondary cell wall (strength and hydrophobicity)

Question 12

Xylem

Answer 12

nutrient and water transport, functional cells are dead at maturity

Question 13

Xylem tracheids

Answer 13

long and narrow, with tapered ends

Question 14

Xylem vessel elements

Answer 14

very wide, have blunt ends and end wall perforation (primary cell wall dissolves at the pit pairs)

Question 15

Phloem

Answer 15

sugar and phytohormone transport

Question 16

Sieve tube element

Answer 16

movement over long distances, devoid of most cell elements at maturity to provide decreased resistance

Question 17

Companion cell (phloem)

Answer 17

has all of the typical cell elements, helps keep the sieve tube element alive

Question 18

Sieve plate

Answer 18

extensive amount of plasmodesmata connections on the end wall of the sieve tube element

Question 19

Middle lamella

Answer 19

occupies the space between adjacent cells, helps glue them together

Question 20

Primary cell wall

Answer 20

established during cell division, increases in surface area as a cell expands

Question 21

What proteins are involved in cell wall loosening?

Answer 21

expansin, XTH, endoglucanases, and pectin modifying enzymes

Question 22

Acid growth hypothesis

Answer 22

cell wall expansion accelerates with acidic conditions, this is because expansin performs better in acidic conditions, and it helps create slippage between bonds

Question 23

C-value paradox

Answer 23

the size of the genome does not always correspond to the complexity of the organism

Question 24

how is genome size measured?

Answer 24

sequencing or fluorocytometry

Question 25

nucleosome

Answer 25

DNA coiled around 8 histone proteins

Question 26

Chromatin

Answer 26

nucleosomes + linker DNA

Question 27

Heterochromatin

Answer 27

tightly arranged chromatin that is not active

Question 28

Euchromatin

Answer 28

transcriptionally active, can be as low as 10-15% of total chromatin

Question 29

Chloroplasts

Answer 29

plastid that performs photosynthesis

Question 30

Chromoplasts

Answer 30

plastid that stores and provides pigment

Question 31

Amyloplasts

Answer 31

plastids that store starch

Question 32

Leucoplasts

Answer 32

plastid that synthezizes and stores secondary metabolites

Question 33

What kinds of solutes are stored in vacuoles?

Answer 33

- mineral nutrients: potassium, nitrates, phosphates - sugars: sucrose, fructose, glucose - organic acids: molate, citric acid

Question 34

tonoplast membrane

Answer 34

lipid bilayer membrane found in vacuoles

Question 35

Peripheral protein

Answer 35

proteins that are easily removed from the plasma membrane

Question 36

Integral proteins

Answer 36

proteins that are not easy to remove from the plasma membrane, very important for solute transport, ex: aquaporins

Question 37

What is the consequence of unsaturated fatty acids in the lipid membrane?

Answer 37

unsaturated fatty acids can cause kinks in the hydrophobic tail, which lead to gaps in the membrane

Question 38

What are the main constituents of the primary cell wall?

Answer 38

cellulose, cross-linking glycans, pectins, and proteins

Question 39

Where is cellulose made in the cell?

Answer 39

on the plasma membrane by the cellulose synthase complex

Question 40

Where are cross-linking glycans and pectin made in the cell?

Answer 40

golgi apparatus

Question 41

Where are proteins made in the cell?

Answer 41

synthesis begins in the cytoplasm, then moves to the ER

Question 42

What is cellobiose?

Answer 42

two units of glucose connected with a beta 1,4 linkage

Question 43

How is cellulose made?

Answer 43

repeating units of cellobiose

Question 44

What is the ultimate precursor to lignin?

Answer 44

aromatic amino acid -> phenylalanine

Question 45

purpose of cross-linking glycans

Answer 45

potentially cross-link cellulose microfibrils, forming a network

Question 46

Where in the cell is lignin synthesized?

Answer 46

cytoplasm

Question 47

anisotropic growth

Answer 47

cell growth can occur in all directions

Question 48

isotropic growth

Answer 48

growth only occurs perpendicular to microfibril orientation

Question 49

meristematic cell function

Answer 49

divide and replicate -> how plants grow

Question 50

the root apex generates new ______

Answer 50

cells

Question 51

where does the majority of nutrient acquisition and water uptake happen?

Answer 51

roots

Question 52

what is the closest thing plants have to a brain?

Answer 52

the shoot and root apical meristems- they process information from different sources and coordinate growth and development of the plant

Question 53

vascular tissue

Answer 53

xylem and phloem- water and nutrient transportation

Question 54

plasmodesmata

Answer 54

on plasma membrane, facilitate communication and transport between cells

Question 55

what genomes are present within a cell?

Answer 55

nucleus, plastids, and mitochondria

Question 56

Arabidopsis thaliana

Answer 56

has one of the smallest plant genomes - was the first plant to ever be sequenced

Question 57

What does the nucleolus do?

Answer 57

assembles rRNA and proteins into large and small subunits

Question 58

thylakoid membrane

Answer 58

- the membranes within chloroplasts - pigments are embedded here - where the light reactions take place

Question 59

pro-plastids

Answer 59

mother plastid that can be turned into a specialized plastid, they don't have an extensive membrane network at this stage

Question 60

granum

Answer 60

stacks of thylakoid membranes inside chloroplasts

Question 61

stroma

Answer 61

- the non-membrane component of the chloroplast - carbon fixation occurs here - rubisco

Question 62

stroma lamellae/thylakoid

Answer 62

the thylakoid connections between granum

Question 63

mitochondria

Answer 63

- semi-autonomous, can divide independently - contains DNA, still requires nucleolar DNA for many proteins

Question 64

replication of plastids and mitochondria

Answer 64

- replication independent of cell division - the cell communicate a need for more - occurs through fission

Question 65

endoplasmic reticulum

Answer 65

- membrane network within the cell - provides membranes components and proteins to other organelles - can extend between cells though plasmodesmata

Question 66

Smooth ER function

Answer 66

lipid biosynthesis and storeage

Question 67

Rough ER function

Answer 67

protein synthesis

Question 68

golgi apparatus function

Answer 68

- pectin synthesis - cross-linking glycan synthesis - accept vesicles from ER and transfer to plasma membrane rndocytosis

Question 69

endocytosis

Answer 69

membrance/vesicle movement from plasma membrane to the golgi apparatus, then to vacuoles

Question 70

pits

Answer 70

regions without a secondary cell wall within vascular tissues, allow water and nutrients to move between cells