Plant structure, growth, and response

Question 1

What does the term Development mean?

Answer 1

The specific series or changes by which cells form tissues, organs, and organisms

Question 2

What factors effect development?

Answer 2

Genetic information inherited from parent but also external environment such as pH, water and minerals

Question 3

What is Developmental Plasticity?

Answer 3

The ability to alter form in response to local environmental conditions

Question 4

A single genotype can produce different phenotypes in different environments.
What is this called?

Answer 4

Developmental Plasticity

Question 5

The three overlapping processes involved in the development of a multicellular organism are

Answer 5

growth, morphogenesis, and differentiation.

Question 6

What is Growth?

Answer 6

An irreversible increase in size

Question 7

What is Morphogenesis?

Answer 7

The process that gives a tissue, organ, or organism its shape and determines the positions of cell types

Question 8

What is Cell differentiation?

Answer 8

The process by which cells with the same genes become different from one another

Question 9

The plane of cell division refers to

Answer 9

development of the new cell wall that bisects a plant cell during cytokinesis

Question 10

What is cytokinesis?

Answer 10

Cell splitting apart

Question 11

What is transverse division and what does it lead to in leaf growth?

Answer 11

Leaf elongation

Question 12

What is longitudinal division and what does it lead to in leaf growth?

Answer 12

Leaf broadening

Question 13

mutations that affect the plane of cell division (e.g., tangled-1) do not affect

Answer 13

leaf shape.

Question 14

Although the plane of cell division does not determine the shape of plant organs, the symmetry of cell division is important in determining

Answer 14

cell fate.

Question 15

What is symmetry of cell division?

Answer 15

The distribution of cytoplasm between daughter cells

Question 16

What is Asymmetrical cell division and what does it signs? Explain Guard Cells.

Answer 16

One daughter cell receives more cytoplasm than the other during mitosis; usually signals a key event in development; Guard cells are the smaller cell in asymmetrical cell division

Question 17

Asymmetrical cell division also plays a role in establishment of

Answer 17

polarity

Question 18

What is the first cell division of a plant zygote like?

Answer 18

normally asymmetrical, initiating polarization of the plant body into shoot and root.

Question 19

What does the establishment of polarity lead to in plants?

Answer 19

Downward growth of roots, upward growth of shoots

Question 20

What is polarity?

Answer 20

The condition of having structural or chemical differences at opposite ends of an organism

Question 21

What happens if the first cell division of a plant zygote is symmetrical instead (e.g., the gnom mutant)?

Answer 21

The first cell division of the zygote is abnormal because it is symmetrical, and the resulting ball-shaped plant has neither roots nor leaves

Question 22

Growing plant cells expand mainly through

Answer 22

water uptake and “packaging” of water in the large central vacuole of the cells.

Question 23

What is the usual orientation of cell growth and how is that determined?

Answer 23

Through “cuttings”; Steam cutting- adventitious roots emerge from the end that was nearest the root; in root cutting- adventitious shoots arise from the end that was nearest the shoot

Question 24

What are cellulose microfibrils?

Answer 24

The orientation of these in the innermost layers of the cell wall causes differential growth; they do not stretch so the cell expands mainly perpendicular to the main orientation of them

Question 25

During morphogenesis, cells acquire different identities in an ordered spatial arrangement. What does that mean?

Answer 25

Certain cells form where they need to be for example dermal tissue forms on the exterior and vascular tissue in the interior

Question 26

What is pattern formation?

Answer 26

The development of specific structures in specific locations

Question 27

Experimental work has shown that a plant cell’s fate is established late in development and largely depends on signaling from

Answer 27

neighboring cells.

Question 28

The gene KNOTTED-1 is important in the development of

Answer 28

leaf morphology

Question 29

Given that the cells of a developing organism share a common genome, what controls differentiation?

Answer 29

Depends to a large degree on the control of gene expression- the regulation of transcription and translation, resulting in the production of specific proteins

Question 30

Gene expression is one thing; how about the final position of a cell in a developing organ? What does cell-to-cell communication have to do with this?

Answer 30

Cells receive information about hoe they should specialize form neighboring cells; this is "cell-to-cell communication"

Question 31

Explain the two cell types that arise in the root epidermis of Arabidopsis: root hit cells and hairless epidermal cells

Answer 31

Cell fate is associated with the position of the epidermal cells; Immature epidermal cells in contact with two root cortex differentiate into root hair cells by not expressing a homeotic gene called GLABRA-2; Immature epidermal cells in contact with only one cortical cell differentiate into mature hairless cells by expressing GLABRA-2

Question 32

What are phase changes?

Answer 32

The morphological changes that arise for transitions in shoot apical meristem activity; 3 phases in plants juvenile stage-> adult vegetative stage -> adult reproductive stage

Question 33

Flower function involves a phase change from

Answer 33

vegetative growth to reproductive growth

Question 34

This phase change involves the conversion of ____ vegetative meristems to ____ floral meristems and is associated with the switching on of floral ____ _____ ____

Answer 34

indeterminant; determinant; meristem identity genes.

Question 35

What are organ identity genes, what do they control, and how do they control it?

Answer 35

A plant homeotic gene that uses positional information to determine which emerging leaves develop into which types of floral organs; ABC hypothesis

Question 36

Explain floral organs and their arrangement.

Answer 36

SEPALS form the first outermost whorl; PETALS form the second; STAMENS form the third; and CARPALS for the fourth and innermost whorl

Question 37

Go through the steps for de-etiolation of potatoes to happen

Answer 37

1. The light signal is detected by the phytochrome receptor 2. Transduction is than initiated by second messengers cGMP and CA2+ channels 3. The second messengers activate two different specific protein kinase 4. Both pathway lead to expression of genes for proteins that function in the response

Question 38

What are second messengers and what do they do?

Answer 38

Small molecules and ions in the cell that amplify the signal and transfer it from the receptor to other proteins that carry out the response

Question 39

What are protein kinase?

Answer 39

Enzyme that works in phosphorylation

Question 40

What is post-translational modification?

Answer 40

Activates preexisting enzymes by having a kinase cascade

Question 41

What is Transcriptional Regulation?

Answer 41

Increases or Decreases the synthesis of mRNA encoding a specific enzyme

Question 42

What are de-etiolation response proteins?

Answer 42

Many are enzymes that function in photosynthesis directly; others are enzymes involved in supplying the chemical pre- cursors necessary for chlorophyll production; still others affect the levels of plant hormones that regulate growth.

Question 43

Plant hormones help (3)

Answer 43

coordinate growth, development, and responses to stimuli.

Question 44

What is a hormone?

Answer 44

is a signaling molecule that is produced in tiny amounts by one part of an organism’s body and transported to other parts, where it binds to a specific receptor and triggers responses in target cells and tissues.

Question 45

What is tropism?

Answer 45

Any growth response that results in plant organs curving toward or away from stimuli

Question 46

What is phototropism?

Answer 46

The growth of a shoot toward light or away from it

Question 47

In 1880, Charles and Francis Darwin removed and covered parts of grass coleoptiles to determine what part senses light. Coleoptile is

Answer 47

the covering of the young shoot of the embryo of a grass seed.

Question 48

Peter Boyce-Jensen separated coleoptiles with different materials to determine

Answer 48

how the signal for phototropism is transmitted.

Question 49

plant growth, development, and responses to stimuli are highly coordinated and under control of multiple chemical agents known as

Answer 49

hormones or plant growth regulators