Plant life cycle and reproduction Flashcards
Name the parts of a flower. Label the male and female parts and others.
Male: Anther and filament
Female: Stigma, style, ovary, ovules
Others: Petal, Sepal
Explain why seeds or fruits need to be dispersed.
It is to prevent overcrowding so that the young plants will not have to compete for space, water, mineral salts and sunlight with the parent plants.
Tube A was filled with cooled boiled water and Tube B was filled with tap water. 3 seeds were put in both tubes. A layer of oil was poured in both tubes before sealing them.
After 3 days kept in a warm cupboard, the seeds in Tube B germinated while the seeds in Tube A did not. Explain why.
There is dissolved air in the tap water in Tube. Thus, with the presence of air, water and warmth, the seeds were able to germinate. There is no air in the cooled boiled water in Tube A as all the air escaped out of the water during the boiling process. The layer of oil also prevented air from dissolving in the water. Thus, without air the seeds in Tube A could not germinate.
How do you tell if a flower is pollinated by wind or animals.
Flowers pollinated by wind have long anthers and stigma that hang out of the petal to catch the pollen grains easily.
Flowers pollinated by animals have large colorful petals, sacs filled with nectar, and an appealing scent to attract pollinators. The anthers are found inside the flower so the pollen is transferred to the animal when it enters the flower to feed on the nectar
Explain why the seeds of the African Tulip can be dispersed further than those of the Saga.
Why might the young plants of the Saga grow as healthily as the young plants of the African Tulip
The seeds of the African Tulip have wing-like structures while those of the Saga do not. The wing-like structures increase the total exposed surface area of the seed in contact with the wind, thus enabling them to stay afloat in the air for a longer time, allowing them to be dispersed further from the parent plant.
The young plants of the Saga are closer to one another, resulting in overcrowding and competition for space, water, mineral salts and sunlight with each other
A seed was placed on some moist cotton balls. A few days later the roots and shoots had grown out of the seed. describe how the roots and the shoot had grew and explain why.
The roots grow downwards to absorb water and dissolved mineral salts for the seedling. The shoot grows upward to obtain more sunlight so that the plant can make more food when the leaves are developed
State one difference between the flowers of a kiwi and mango and explain your answer.
The flower of the kiwi has many ovules while the flower of the mango only has one.
After fertilization, the ovules in the flower will develop seeds. The kiwi has many seeds so the flower has many ovules while the mango has only one seed so the flower one ovule.
Plant B was noticed to be growing only near the river. Describe one likely characteristic of the seeds of Plant B.
Give a reason why
The fruits have fibrous husk. Plant B was found growing only near the river so the seeds are likely dispersed by water. The fibrous husk trap air to help the seed float on the water.
Fruit A is fleshy and juicy. Explain how having a hard seed coat is important for the dispersal of the seeds of Fruit A.
Fruit A is fleshy and juicy, thus the seeds are likely dispersed by animals when the seeds are passed out in the waste. The hard seed coat protects the seed from being digested when the fruit is eaten by animals
