Plant Biology Flashcards
What is the function of the root?
- Anchor the plant to the soil
- They penetrate deep into the soil, absorbing water and minerals
What is the function of the stem?
- They support the leaves flowers, fruits and buds
- It holds the leaf upright so it can trap the sunlight it needs for photosynthesis
What is the function of the leaves?
- It has a green chlorophyll found in chloroplast
- Chlorophyll helps to trap sunlight so the leaf can make food for the plant
What is the function of the flower?
- Reproductive part of the plant
- Carry out pollination and form fruits and seeds after fertilization
- They only appear certain times in the life cycle of a plant
What is Photosynthesis?
The process by which leaves in the presence of sunlight and chlorophyll use carbon dioxide and water to make glucose. Oxygen is released as a byproduct.
Word equation for photosynthesis?
Carbon Dioxide + Water ——-> Glucose + Oxygen
Simple Equation for photosynthesis
6CO² + 6H²0 —————> C⁶H¹²0⁶+ 60²
What is the process of photosynthesis?
Water is absorbed by the roots of plants through osmosis. Carbon dioxide is diffused into the plants through the stomata. Sunlight is absorbed by the leaf’s chloroplast.
Inside the leaf, the sunlight causes the water to seperate into hydrogen and oxygen. The hydrogen and carbon dioxide combine to form glucose. Oxygen is released as a byproduct.
(Water is oxidized, loses electrons and turns into oxygen and carbon dioxide is reduced and gains electrons and turns into glucose)
Factors affecting photosynthesis?
- Temperature- Photosynthesis requires enzymes to carry out the reaction. As these enzymes have an optimum temperature, photosynthesis also has an optimum temperature. This is usually 25’C
- CO2- Directly proportional
- Light intensity- Directly proportional
Storage of Glucose
- Starch and Lipids in seeds
- Transported to the Mitochondria to be used for plant respiration
- Glucose monomers join to form cellulose (carbohydrate) used to build or add strength to cell walls
- Glucose and nitrate ions join to form amino acids or proteins
Parts of the leaves:
Upper & Lower Epidermis
Cuticle
Palisade Mesophyll Cell
Spongy Mesophyll Cell
Vascular Bundle
Bundlesheath Cell
Xylem
Phloem
Guard Cells
Stomata
Function of Cuticle:
- Waxy Layer
- Protects from bacteria
- Prevents water loss
- Allows light to pass through
Function of Epidermis (Upper and Lower):
- Allows maximum light to pass through (Transparent)
- Protection
- Prevents excessive water loss
- Secretes waxy cuticle
- Does not have chloroplast
Palisade mesophyll vs Spongy mesophyll
Palisade mesophyll:
- Tall
- Tightly packed
- Contains chloroplast
Spongy mesophyll:
- Irregularly Shaped
- Air spaces in between for gas exchange
- Contains chloroplast
Function of Vascular Bundle
Contains transport tissue/conducting vessles