Assignment 23
Unique No:
DUE 2025
,QUESTION 1 – Practical Applications of Osmosis and Diffusion in Nature [10]
1. Water Uptake by Plant Roots (Osmosis)
Process:
Root hair cells typically have a higher concentration of dissolved substances
(minerals and salts) compared to the water in the surrounding soil. Due to this
difference in concentration, water moves into the root hair cells through their
selectively permeable membranes by osmosis.
Function in nature:
This mechanism supplies plants with the water needed to transport minerals,
maintain turgor pressure, and keep tissues firm for structural stability.
Importance:
Without osmotic absorption, plants would wilt, lose rigidity, and experience
reduced photosynthetic efficiency.
2. Gas Exchange in Alveoli of the Lungs (Diffusion)
Process:
Within the alveoli, oxygen is present in higher concentration than in the blood
flowing through nearby capillaries. This causes oxygen to diffuse into the blood,
while carbon dioxide moves from the blood—where its concentration is higher—
into the alveoli to be exhaled.
Function in nature:
This bidirectional diffusion supports aerobic respiration, which is essential for
energy production in living organisms.
Importance:
Efficient diffusion in the lungs is necessary for adequate ATP generation, which
sustains all life processes.
3. Salt and Water Regulation in Marine Fish (Osmosis)
, Process:
In seawater, the external salt concentration is higher than that inside a fish’s
body. Water naturally leaves the fish’s tissues through osmosis. To counteract
dehydration, marine fish drink seawater and excrete excess salts via specialised
cells in their gills.
Function in nature:
Enables marine fish to maintain fluid balance and survive in high-salinity
environments.
QUESTION 2 – Role of Embryology in Commercial and Agricultural Industries [10]
1. Artificial Insemination and Selective Breeding in Livestock
Process:
By understanding early embryonic development, farmers can determine the
optimal time for fertilisation, collect semen, and carry out artificial insemination.
Techniques such as embryo transfer are also used to place fertilised embryos
into surrogate mothers.
Example:
In dairy farming, bulls with traits linked to higher milk yield are selected. Farmers
synchronise ovulation cycles in cows and implant embryos into other females to
increase the number of offspring from top-quality genetics.
Industry benefits:
Increases productivity, enhances desirable traits, and helps reduce the
prevalence of inherited diseases.
2. Hatchery Practices in Poultry Production
Process:
Embryology guides the control of incubation factors, such as temperature,
humidity, and egg rotation, which are critical for proper embryo development.