Chapter 36 - Plant form and function

Primary growth _____. a) produces epidermal, ground, and primary vascular tissues b) substantially increases the girth of the plant c) never occurs in leaves d) results from the activity of the cork cambium

A

Secondary structures are often analogous to primary structures. What primary structure is bark analogous to? a) epidermis b) branches c) cuticle d) thorns

A

What do axillary buds produce on a stem? a) Branches b) Leaves c) Lateral roots d) Seeds

A

What is an apical meristem?

A group of undifferentiated plant cells, at the tip of a stem or root, that is responsible to primary growth

What is a tap root?

A large vertical main root of plant

What is a lateral meristem?

A layer of undifferentiated plant cells found in older stem and roots that is responsible for secondary growth -also called cambium or secondary meristem

What are the two styles of growing in plants?

Addition and elongation

What is the difference between annuals, biennials, and perennials?

Annuals: life cycle completed in one year. Eg. Banana trees Biennials: life cycle spans over 2 years - over winter and reproduce in second year Perennials: live for many years

A totipotent cell is one that _____. a) has a thick secondary wall b) retains the capacity to divide and form an entirely new plant c) is dead at maturity d) conducts water or nutrients in the plant

B

Plants need secondary growth to _____. a) increase the length of stems and roots and thus increase a plant's ability to absorb photons and acquire carbon dioxide, water, and ions b) increase the width of stems and roots, providing more conducting tissue and additional support c) produce new leaves d) produce a more extensive root system

B

Vessel elements are cells found only in angiosperms. Which of the following statements best defines the characteristics of vessel elements? a) Vessel elements are specialized for support. They are long, narrow cells with a thick secondary cell wall. b) Vessel elements are specialized for water transport. They are short, wide cells with openings known as perforations that connect one cell to the next. c) Vessel elements are specialized for sugar transport. They are living cells with a thin primary cell wall. d) Vessel elements are specialized for cell division. They are small cells found in meristems.

B

Which of the following are found in both animal and plant cells? a) chloroplasts b) mitochondria c) cell walls d) vacuoles

B

Which of the following provides an example of phenotypic plasticity? a) Some plants have simple leaves, whereas others have compound leaves. b) An individual tree growing in a waterlogged environment may have shallow roots, whereas another individual of the same species growing in dry soil may have deep roots. c) Cactus plants have modified stems that help them adapt to the desert environment. d) Some plants have taproots, whereas other plants have fibrous roots.

B

Which of the following statements about mature sclerenchyma cells is true? a) They support actively growing parts of the plant. b) They usually have no cytoplasm. c) Fibers and sclereids function in both support and the transport of water. d) They produce a secondary cell wall composed only of cellulose.

B

If you were looking for cells undergoing mitosis in a plant, where would be the best place to look? a) Leaves b) Epidermis c) Meristems d) Xylem

C

What secondary meristem(s) produce(s) the layers of bark on a tree? a) cary cambium b) apical meristem c) both vascular cambium and cork cambium d) vascular cambium

C

Which cell type would likely aid in healing an injury to a plant's stem? a) sclerenchyma b) sieve-tube members c) parenchyma d) tracheids

C

Which of the following statements best explains why wood cells produced in the fall are smaller and thicker-walled than those produced in the spring? a) The wood cells divide more often in the fall than in the spring. b) There is less food for the wood cells to conduct in the fall. c) There is more water available in the spring. d) The tree produces different kinds of cells during different seasons.

C

Why is the root apical meristem covered by a thimble-shaped cap, whereas the shoot apical meristem is not? a) Roots seek out water; shoots do not. b) To respire, the shoot apical meristem cannot be covered. c) Roots need protection as they push through the soil. d) The root cap senses gravity, and shoot apical meristems do not need to sense gravity.

C

Stomata allow for gas exchange between the tissues of a leaf and the atmosphere. One gas that exits the leaf is water vapor. In which of the following situations would a leaf lose the most water? a) cool day b) sunny, calm day c) rainy day d) sunny, windy day

D

The vascular cambium _____. a) develops into cork cells b) produces cells that differentiate into secondary xylem and phloem c) is a type of apical meristem d) produces cells that differentiate into primary xylem and phloem

D

What are the different life history types found in plants?

Different life histories can be seen in the rings of wood • Vascular cambium produces lots of secondary xylem and some secondary phloem • Cork cambium produces cork cells on the outside and "cork skin" on the inside • Cabium stops growing during winter or the dry season. This results in small, thick-walled cells in wood (latewood) • Cambium divides rapidly during rainy months and spring leading to larger thin- walled cells (earlywood) • Together, alternating late and early wood constitutes wood rings

Layers of monocot:

Epidermis -> Cortex -> endodermis -> stele -> pericycle -> phloem -> xylem -> pith

What are function of leaves?

Function: used for absorbing light - is a photosynthesis organ. - can be used for reproduction - and some are modified for storage of water Eg. Modified leaves = tendrils - blade, stalk, petiole (only dicots have petioles), venation (parallel in monocots and reticulate in dicots)

What is intermediate growth?

Growth occurring because of meristems

What is the difference between heartwood and sapwood?

Heatwood: -dark-coloured -inner xylem region Sapwood: -light-coloured -outer xylem region

Where does most of the absorption of water in roots occur?

In the root hairs

What is apical dominance?

Inhibitor of lateral bud growth by apical meristem at the tip of a plant branch

What happens to the epidermis during secondary growth?

It expands and the cork cambium adds cells primarily to the outside

Know the different leaf types.

Leaf types: 1. Simple 2. Compound 3. Double compound.

What are the three cell types in tissues?

Parenchyma, Collenchyma, and Sclerenchyma

What is phloem?

Phloem: - responsible for moving sugars - functional phloem cells = alive - have sieve tube members, which are very specialized and stacked end to end and surrounded by companion cells

What's the difference between the pith and the cortex?

Pith: Vascular bundles inside ground tissue Cortex: Vascular bundles outside of ground tissue

What are the two types of growth?

Primary: growth from aperical meristem, root grows longer, trees taller, use elongation Secondary: growth from lateral meristem (set up like cylinders) - results in stem/ root thickening -

What are the two organ systems in plants?

Root and Shoot system. Shoot system: -Vegetative portions • Stems and leaves - Reproductive portions • Flowers and fruits Root system: - responsible for absorbing water and minerals

Root anatomy:

Root hairs: increase surface area of absorbing water and nutrients - where most of water is absorbed and possess proton pumps Meristem: embryonic cells that divide rapidly Apical meristem: dividing cells at/toward tip of root and shoot of plant Epidermis: boundary between plant external environment Cortex: includes endodermis = inner most layer of cortex (ground tissue) Stele: vascular tissue Pericyle: ring of cells surrounding xylem and phloem

The Shoot System - what is it and how is it involved in plant growth?

The Shoot system involves getting the leaves where they need to be to get light. The system is made up of nodes and internodes - where ever there is a bud, there is an apical meristem (two types of buds off of stem: axillery and terminal. Terminal buds suppresses growth in axillery bud)

What is the zone of quiescent?

The part of the apical meristem cells that don't grow as quickly

What is primary growth?

The process of the plant growing vertically, by cells in the apical meristem dividing, enlarging, and differentiating - the root and shoot tips extend the plant body outward, allowing it to explore new space

Anatomy of a leaf:

Top: Light-side - more lighter and colorful Underside: hazy, looking through epidermis Generally: 1. Cuticle - water leak prevention 2. Epidermis 3. Mesophyl - In dicots, there are two layers of mesophyl (upper = pallisade, and lower = spongy) - Mesophyl contains lots of chloroplast to absorb light rays 4. Epidermis 5. Stomata cells: can open or close - where gas exchange occurs - located on bottom of leaf - only place where water can evaporate - found only in leaves and modified leaves

What is xylem?

Xylem: - include tracheid cells and vessel element cells - they are elongated, and stacked from end to end - functional xylem cells = dead

The root and shoot systems of plants are dependent on each other. Which statement best describes the specific roles that the shoot and root systems perform? a) The shoots obtain CO2 and water from the atmosphere and create macromolecules using energy from sunlight, whereas the roots absorb water and minerals such as N, P, and K from the soil. b) The shoots obtain CO2 from the atmosphere and create macromolecules using energy from sunlight, whereas the roots absorb water as well as minerals such as N, P, and K from the soil. c)The shoots obtain CO2 as well as minerals such as N, P, and K from the atmosphere and create macromolecules using energy from sunlight, whereas the roots absorb water from the soil. d) The shoots create macromolecules using energy from sunlight, whereas the roots absorb water, CO2, and minerals such as N, P, and K from the soil.

b

Why does damage to the phloem sometimes kill trees?

(Girdling) cuts of transportation of important things

Describe parenchyma cells.

- non-specialized - Performs a variety of metabolic processes like photosynthesis, starch synthesis -Totipotent (allows for "seedless" plants like bananas, seedless grapes,etc. to be propagated) - Eg. Phloem

Describe Collenchyma cells.

- specialized - Thick cell walls support the plant body at growing regions of shoots - Constitute "strings" in vegetables (e.g. celery or rhubarb strings)

Layers of eudicots:

- thicker roots, more organized and centralized, starch storage, Some tissue types: - no pith - xylem in center - surrounded by phloem bundles - pericycle surrounds phloem

What are vascular bundles? Know how to label the cross-section of a monocot and eudicot cross-sections

- vessels that consists of xylem and phloem, supporting, and protective tissues

Root System: Function? Difference between monocot and dicot?

-- pulling water and nutrients out of soil-anchor plants in ground - holding tree down Monocots: Fibrous root system Dicots: taproot (main root with little ones coming off) - Eg. Carrots and oak trees

Describe sclerenchyma cells.

-specialized for support Produce thick secondary cell wall -Cells are dead at maturity; found primarily in non-growing regions - fibers (xylem) or sclerids (stone cells)/(bundles) - Eg. Skin of avocado or graininess of pear

What are modifications on the shoot system?

1. Stolon (runner) - horizontal stem - grows new set of roots and shoot - vegetated reproduction 2. Rhizome - involves root underground - helps to sprout new plant 3. Bulb - in winter- type of root 4. Tubes - store starch - a type of root underground Eg. Greenbrier weed - have thorny rhzchmes

What are the three types of plant tissue?

1.) Dermal - surrounds outside of plant, 1 cell thick, covers shoot with waxy cuticle to prevent water loss (Component tissues include epidermis and periderm) 2.) Vascular - responsible for moving water (with direction) and sugars from place of production to consumption. 2 Types: Xylem and Phloem 3.) Ground - responsible for Photosynthesis, Food storage, Regeneration, Support, Protection - includes Parenchyma tissue, Collenchyma tissue, and Sclerenchyma tissue

What are the three primary meristem divisions of an apical meristem?

1.) Protoderm - gives rise to dermal tissue system 2.) Ground meristem - gives rise to ground tissue system 3.) Procambium - gives rise to vascular tissue system

What are the three zones at the root tip?

1.) Zone of cellular division: - contains the apical meristem, where cells actively divide 2.) Zone of cellular elongation: - is made up of cells that are actively increasing in length 3.) Zone of cellular maturation: - where older cells complete their differentiation into dermal, vascular, or ground tissues

What accounts for most of the cells in a piece of wood?

Cork cells

What comprises the bark?

Cork cells, cork cambium, and secondary phloem