Plants: Specialized and Organized (Part 1) Flashcards
What functions need to be carried out by the leaf of a plant?
- Photosynthesis
- Produces waste
- Reproduce
- Move/respond to env’t
- Grow
The leaf has many different types of cells: cell specialization
In a single-celled organism, one cell performs all the functions of life. In multi-cellular organisms, groups of similar are specialized to perform specific tasks. What are these groups called?
Tissues
(As a reference and example) Name 4 specialized cells in the human body.
- Muscle
- Skin
- Nerve
- Blood
What is photosynthesis?
Occurs in chloroplasts (green parts) of plant cells.
6CO2 (g) + 6H2O (l) + light + (chlorophyll) -> C6H12O6 (s) + 6O2 (g)
Net production of oxygen and net loss of carbon dioxide
What is cellular respiration?
It occurs in the mitochondria of plant and animal cells. [Everyone]
C6H12O6 (s) + 6O2 (g) -> 6CO2 (g) + 6H2O (l) + ATP
Net loss of oxygen and net production of carbon dioxide.
Do photosynthesis and respiration occur at the same time or at different times?
Different times or different places in the plant (roots in a day, for example)
What are epidermal cells?
Make up the epidermis (skin)
a) Description:
- a flat, single layer of cells covering the upper and lower surfaces of the leaf
- transparent, which allows solar energy to pass through
- a waxy cuticle coats the cells to prevent evaporation of water
b) Function:
- To protect the leaf
- These don’t contain chloroplasts
What are palisade tissue cells?
a) Description:
- long and narrow (column-like) cells packed closely together lying just below the upper surface
b) Function:
- Photosynthesis
- Mostly made of chloroplasts
What are spongy tissue cells?
Lungs
a) Description:
- round, loosely packed cells found just below the palisade layer
b) Function:
PRIMARY
- water and gas exchange
SECONDARY
- Photosynthesis (packed with chloroplasts)
- Helps plants to catch that little bit extra of light
What are stomata and guard cells?
a) Description:
- stomata (plural), stoma (singular)
- stomata are tiny openings on the underside of a leaf
- each stoma is controlled by two guard cells (which both have chloroplasts)
b) Function:
Stomata allow the exchange of CO2, O2, and water vapour, by letting them into the leaf
What are vascular tissue cells?
Circulatory system
a) Description:
- A series of tubes or leaf veins called xylem and phloem which are arranged together in vascular bundles
b) Function:
Xylem: carries water and minerals from roots to leaves
Phloem: carries sugars made by the leaves to other parts of the plant down
No chloroplast
Name three advantages multi-cellular organisms have over single-celled organisms.
- Larger body size
- Specialized cells
- More diversity allowed (increased survival)
Multicellularity requires a higher degree of organization to perform functions efficiently. Humans have about 100T cells. Name the levels of organization.
[Organelles] kind of…
Cells: basic unit of organization (stomach cells, phloem cells)
Tissues: many cells with the same structure and function clustered together (muscle tissue, epidermal layer)
Organs: multiple tissues working together to perform a specific function (stomach, leaf)
Systems: organs/tissues working together to perform a complex function (digestive, vascular)
Organisms
The reactants of photosynthesis are
A) light and carbon dioxide
B) light and water
C) oxygen and water
D) carbon dioxide and water
D
A reactant is any substance that will undergo a chemical change in a reaction. During photosynthesis, carbon dioxide and water are converted to glucose and oxygen within the chloroplasts of a plant cell using the sun’s energy.
Here is the basic formula for photosynthesis with (reactants shown in red):
6CO2 + 6H2O –Light–> C6H12O6 + 6O2
