Adaptations

of Plant

Photosynthetic

Systems: Leaf

and Stem

Design

By: Breana Hull

and Duc Vo

Photosynthesis

Using CO2 and H2O to form O2

and sugar, using energy from

sunlight

Enzyme used called Rubisco

Form and Anatomy-

Shoot System

The shoot system of a

plant is composed of all features that are

above the ground

Common features of

plants are:

Apical bud

Stem

Blades

Stem The steam of a plant is the

thick structure which all other shoot features deviates

Made up of nodes and internodes

Nodes--points of attachments for leaves

Internodes--areas between nodes resulting from plant growth but is not accompanied by leaves. Holds the plant upright and house the internal plant organs necessary to sustain photosynthesis(Xylem & Phloem)

Xylem

Cells specialized in the conduction of water and its transport from the root upward towards leaves.

Two types: Tracheid's & Vessel Elements

Dead cells that produce long ducts that water can adheres to and propel up the shoot.

Proliferated with pits that allow movement between cells.

Tracheid's are longer with tapering end

Vessel elements are wider with shorter segments that stack on top of one another

Phloem

Live functioning

cells with no major

organelles present

in other cells(i.e.

nucleus or

ribosomes)

Specialized in

sugar and mineral

transport to cells

and from cell-to-

cell.

Apical Bud

Resides at the tips of stem

Location of meristems, which

aid in elongation of

plants(primary growth).

Blade (Leaf)

Where the majority

of photosynthesis

takes place.

Uptake of carbon

dioxide and

release of oxygen

via stomata made

up of two guard

cells.

Blade (Leaf) cont…

Outermost layer of leaf and whole plant is the

cuticle; waxy film that prevent water loss.

Epidermis a closely packed single cell layer that

form a membrane around the organism.

Protective in function.

Two layers of mesophyll: palisade and spongy

Palisade are long while spongy are round and

smaller in size located near stomata.

Are made up of parenchyma cells

Parenchyma Cells

Function mainly in the photosynthetic

process of plants.

Large central vacuole

Majority of chloroplasts in plants

Serve in production and storage of

energy rich products.

ChloroplastOrganelle within the cells of the leaves

filled with Chlorophyll that absorbs

sunlight, making it appear green

Where photosynthesis takes place

The Photosystems- (Light Reaction)

Pigment Molecules

Light-harvesting complexes

Reaction-center complex

Primary electron acceptor

Calvin Cycle- (Dark Cycle)

Bryophytes Moss

Single layer leaf

structure

Low growing and

high number of

leaves on stem

maximize

photosynthesis

and carpeting of

available space.

Prefer moist areas

Seedless Plants--

Whisk Fern

Warm tropic

conditions

Leaves are highly

reduced to

prevent

desiccation

Seed Plants--

Nerium Oleander

Subtopic habitat

Thick cuticle and

epidermal layers

decrease level of

water loss.

Stomata are

located in cavities

to prevent water

loss from dry wind.

StomataBalance the requirement for water

conservation for photosynthesis

Surrounded by guard cells which control

the opening and closing of the stomata

In low water and high temperature

conditions, they can close their stomata

to prevent water loss

Guard cells

They close when become turgid with water, water is then released into the stomata to re-open

Water is stabilized in and out of the guard cells as potassium ions are transported across the plasma membrane, regulating the amount of water and ions taken in

Some plants use an alternate mechanism for

hot, arid climates to conserve water,

nutrients and regulate photosynthesis. These

are also used as an alternate mode of

carbon fixation.

These include:

C3

C4

CAM

C3

Cool, moist conditions

Most plants, normal conditions

Stomata open during the day

Photosynthesis occurs throughout the leaf

C4 Plants

This minimizes photorespiration and maximizes sugar production. Includes corn and sugarcane plants

Have unique leaves for photosynthesis and designated cells

two types of cells: bundle-sheath cells- tightly packed around the veins of the

leaf: contain chloroplasts

mesophyll cells- in between the bundle-sheath and leaf surface, loose- convert CO2 into organic compounds

Photosynthesizes quicker because the CO2 is being delivered straight to the enzymes, preventing photorespiration; good under hot and light conditions

CAM

In water storing plants, like cacti, pineapple

Open stomata at night and close it during the day, to avoid the harsh climate

Mesophyll cells store organic acids in vacuoles over night and release them the next morning; when light reactions can take place in the day, the sugar can then be incorporated into the chloroplasts

Interesting Story

Researchers from Arizona State

University, in 2005, found the first

organism that lives 1 mile deep in the

ocean that performs photosynthesis.

Since no sunlight reaches this far in

the sea, it has been determined that

these use the dim radiation from

hydrothermal vents.

References Campbell, Neil. 2010. Biology. Edition 8. Pearson Education, Inc. “pages 200-202, G-7”

Desert Ecology of Tucson, AZ. August 12, 2008. Types of Photosynthesis. Pima Community College. http://wc.pima.edu/Bfiero/tucsonecology/plants/plants_photosynthesis.htm. “January 24, 2011”

Almost Eden. 8 Oct 2009. White Oleander. Almost Eden. <http://www.almostedenplants.com/shopping/shopexd.asp?id=732>. “Accessed on 1/22/2011.”

Plant Structure and Function. <http://www.uic.edu/classes/bios/bios100/labs/plantanatomy.htm>. “Accessed on 1/22/2011.”

Jan A. Nilsson. 2004. Classification: Plantae. Jan A. Nilsson. <http://www.southtexascollege.edu/nilsson/4_gb_lecturenotes_f/4_gb_22_cla_pla_j_spr2003.html>. “Accessed on 1/22/2011.”

The University of New Mexico. 2002. The University of New Mexico. <http://biology.unm.edu/ccouncil/Biology_203/Summaries/Flowerin gPlants.htm>. “Accessed on 1/22/2011.”

Uberraschungsbilder. 28 Mar 2006. Green tree moss. Wikimedia Commons. <http://commons.wikimedia.org/wiki/File:Green_tree_moss.jpg>. “Accessed on 1/22/2011.”

Mr. Girard’s Biological Sciences Website. 14 Jan 2011. Stems. Plainville High School. <http://phsgirard.org/index.html>. “Accessed on 1/22/2011.”

M. J. Farabee. 6/6/07. Parenchyma. M. J. Farabee. <http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookplantanat.html>. “Accessed on 1/22/2011.”

Ms. Turin. 12 May 2009. Cheat sheet. WordPress.com. <http://1mkturin.wordpress.com/category/biology/>. “Accessed on 1/22/2011.”

Benjamin Cummings. 2009. Photosystems. PBWorks. <http://avonapbio.pbworks.com/w/page/9429291/Chapter-10>. “Accessed on 1/22/2011.”

Cambell, Neil A. Jane B. Reece. 2008. Biology. Eighth Edition. Pearson Benjamin Cummings. “See page 199.” “Accessed on 1/22/2011.”

Pearson Education, Inc. 2004. Chemical Products of Light Reactions. Pearson Education, Inc. <http://knight.noble-hs.sad60.k12.me.us/content/exploringLife/text/chapter8/concept8.2.html>. “Accessed on 1/22/2011.”