Summary Sheets 8B the Plant Kingdom Organisms Are Classified Into Groups

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Summary Sheets 8B The plant kingdom Organisms are classified into groups. The plant kingdom contains organisms that have green leaves, cell walls made of cellulose and can photosynthesise. Kingdoms are subdivided into smaller and smaller groups. The last two of these are the genus and the species. The names of these two groups are used to give each species a two-word scientific name. Biodiversity The range of species in an area is called biodiversity. We should preserve biodiversity because: ● organisms depend on one another (they are interdependent) ● we won’t be able to make use of organisms if they become extinct ● more biodiverse areas recover better from natural disasters. Sexual reproduction in plants Reproduction produces new living things (offspring). Sexual reproduction needs two parents to produce sex cells or gametes. The gametes fuse to produce a fertilised egg cell or zygote. The zygote uses cell division to grow into an embryo, which can grow into an adult and become a parent (completing its life cycle). The offspring from sexual reproduction contain characteristics from both parents. The differences in these characteristics is inherited variation. Gametes are produced by reproductive organs. In plants, these are contained inside flowers.

The pollen grains made in the anther need to be carried to the stigma of another flower. They are usually carried by insects or the wind. The carrying of pollen from an anther to a stigma is called pollination.

Once on the stigma, a pollen grain grows a pollen tube, which enters the ovule containing an egg cell. The nucleus from the male gamete inside the pollen grain joins with the nucleus inside the egg cell to form a zygote. This is called fertilisation. The zygote grows into an embryo and the ovule becomes a seed, containing the embryo and a food store. A part of the flower forms a fruit. This is used for seed dispersal, which stops the new plants competing with the parent plants for water, nutrients, light and space. ● Some fruits are eaten by animals and the seeds come out in their faeces (e.g. apples). ● Some fruits are carried on the fur of animals (e.g. burdock). ● Some fruits are carried by the wind (e.g. dandelion). ● Some fruits explode, scattering the seeds (e.g. lupins). When conditions are right, seeds germinate. The resources needed are water, oxygen and warmth (WOW). Water allows chemical reactions to start, which break down the food store and allows cells in the embryo to swell up. Oxygen is needed for respiration, to release energy from the food store. Warmth is needed to speed up the chemical reactions. The root grows first then the shoot. Finally new leaves open and photosynthesis can start in the chloroplasts. The glucose from photosynthesis is turned into starch to be stored.

A growing plant needs light, air, water, warmth and nutrients called mineral salts (LAWWN).

Asexual reproduction in plants Some plants can reproduce using asexual reproduction. This is when one parent plant is able to produce offspring (e.g. by using runners in strawberries or tubers in potatoes).

Accuracy, estimates and sampling We can take a small sample of a larger population and use it to estimate what the larger population is like. Plant populations in an area can be estimated by taking samples using a quadrat. The more samples we take the more accurate the estimate is likely to be but the longer it will take to do.

© Pearson Education Ltd 2014. Copying permitted for purchasing institution only. This material is not copyright free. 16 Page 2 of 2 Evaluating seed dispersal 8Bd-10 1 Scientists mapped the locations of four species of tree in a forest in Malaysia. Each tree used a different method of seed dispersal. One attracted animals to its branches to eat its fruits, another had seed pods that dried up and flung the seeds into the air. Another tree had fruits that fell to the ground and either rolled away or were moved by animals digging in the earth or eating the fruits. Another had seeds with wings like a helicopter, which fluttered to the ground. a Look at the maps below. Which map corresponds to each type of seed dispersal? Explain your reasoning in each case.

b Suggest which method of seed dispersal is the best. Explain your reasoning. (To answer this question, you first need to define what you mean by ‘best’.) The scientists then examined 561 species of plant in the area. They looked for groups of each species (‘clusters’). They measured the diameters of the clusters to show how far each species spread. The bar chart shows how the mean cluster diameter depends on the type of seed dispersal. The fruits eaten by animals were divided into three groups, depending on the size of the fruit. c Which method of seed dispersal was the most successful in this area? Explain your reasoning. d Suggest a habitat in which this method of seed dispersal may not be the most successful. Explain your reasoning. 2 Seedless fruits are very popular, and some are made by hybridising different types of plants. For example, seedless watermelons are produced by breeding a D watermelon with a T watermelon. The fruits produced contain small white flecks but no large black seeds. a Describe what happens after pollination of watermelon T flowers with watermelon D pollen. b Suggest why seeds fail to form but the fruits do.

I can… ● evaluate seed dispersal methods ● describe the formation of seeds and fruits.

1 a What happens during germination?

b Which part of an embryo grows out of a seed first. Tick () one.  root  shoot  seed coat  food store c Complete the words to describe the resources needed for germination. W O W . d Choose one of the resources from part c and explain why it is needed.

2 Complete the sentences using some of the words in the box.

The raw materials for photosynthesis are and . The sugar made by photosynthesis is called . gas is also produced. Photosynthesis needs energy transferred by .

carbon dioxide cellulose chlorophyll glucose light oxygen water

3 Look at the drawings of the tree. Answer the questions by ticking () one box for each. a In which drawing will the tree release the most oxygen?  A  B  C b In which drawing will the tree release the

most carbon dioxide? A B C    c Which process releases carbon dioxide?  respiration  chemical reaction  nutrition  photosynthesis d Which of these is a raw material that the process in part c needs?  glucose  water  energy  carbon dioxide 4 Bees and some flowering plants are interdependent.

a How do the bees depend on flowers?

b How do the plants depend on bees?

c Why is it a problem for humans if there are fewer bees?

I can… ● describe what happens in germination ● explain what resources seeds and plants need ● describe how organisms are interdependent.

© Pearson Education Ltd 2014. Copying permitted for purchasing institution only. This material is not copyright free. 37 Plant life cycle 8Be-5 1 a Cut out the cards and match each picture with the correct sentences. b Arrange the pictures into a life cycle, and add some arrows. I can… ● recall the stages in the life cycle of a flowering plant ● describe how flowering plants reproduce sexually.

Pollination is when pollen from one flower lands on the stigma of another flower. Pollen grains are made by the male reproductive organs.

Fertilisation is when the nucleus from the male gamete in the pollen grain

joins with the nucleus from the egg cell. The egg cells are found inside the female reproductive organs.

Germination is when the A plant continues to grow After fertilisation a seed is seed starts to grow. all through its life. formed, which is often surrounded by a fruit.

Name Class Date

1 Draw lines to link the processes with what happens in each process. Draw more lines to show the order in which the processes happen. One has been done for you.

Order Process What happens

1 fertilisation The plant makes flowers.

2 flowering The plant is old enough to have flowers.

3 germination Fruits are carried away from the parent plant.

4 mature plant The male gamete joins with an egg cell.

5 pollination The seed starts to grow a tiny shoot and root.

6 seed dispersal Pollen grains land on a stigma.

2 Circle the resources a seed needs to germinate. light mineral salts oxygen warmth water 3 Look at the drawing of the seed. Describe the functions (jobs) of the parts labelled X and Y.

The function of part X is

The function of part Y is

4 Complete the following word equation, which sums up what happens in respiration.

oxygen + glucose  + . 5 Explain why a plant will not grow if it does not have enough light.

I can… ● recall the stages in the life cycle of a flowering plant ● recall the resources needed for germination ● describe what happens in germination ● recall what happens in respiration and photosynthesis.

1 Look at this packet of seeds. a When should Lavatera seeds be planted (sown)? b How many months does it take, after germination, for a Lavatera plant to be able to reproduce sexually? c If you plant these seeds in December, they can germinate. Suggest why you would not want to plant these seeds in December. d Which part of the Lavatera seedling will emerge first from the seed? e What does this part do? f What two substances does a seed need to germinate? g What does it need these substances for? h From where does the growing seedling get its supply of glucose for respiration?

2 During the last 200 years, the UK has lost 97% of its wildflower meadows. a Describe an effect this has had on insect populations and explain your reasoning. b Suggest how this might affect humans. Explain your reasoning.

3 Copy and complete these word equations to show what happens in respiration and photosynthesis.

glucose +  + water

water +  + glucose

4 Wild primrose seeds will only germinate after the seeds have spent a couple of months in wet and cold conditions. a Suggest what part of a primrose seed stops the embryo root emerging. b Suggest how the conditions in which the primrose seeds are kept alter this part of the seed to eventually allow germination. c What is the advantage for wild primrose plants of having seeds that only germinate after a period in wet and cold conditions?

5 Bumblebees and wild primroses are interdependent. Explain what this statement means.

I can… ● explain why seeds and plants need certain resources ● describe how organisms are interdependent.

© Pearson Education Ltd 2014. Copying permitted for purchasing institution only. This material is not copyright free. 44 Germination and 8Be-8 photosynthesis 1 The experiment on the right was set up. a What substance would you test for in the leaves to see if photosynthesis was occurring? b How would you do this test? c What result would you expect if you did this test on leaf A? Explain your reasoning.

2 A variegated leaf has some white patches on it. While still growing on the plant, one variegated leaf had a piece of metal foil placed over it, as shown. a Make a drawing of the leaf, without the metal foil. Shade in the area in which you would expect photosynthesis to occur. b Explain why you have shaded your leaf in this way. c What part of a plant cell contains chlorophyll?

3 The terms used by most scientists to describe the different parts of a bean seed are shown in the drawing on the right. The micropyle is a tiny canal through which water can enter. a Explain the functions of the different parts of the seed (apart from the micropyle). b Why do you think the radicle is just above the micropyle?

4 Many seeds do not require light to germinate but some do. Light from the Sun contains different Light sequence Mean colours of light, including ‘red light’ and ‘far red light’. (5 mins total) percentage of Red light is absorbed by leaves. Far red light goes germinated through leaves. An experiment was done to see how seeds Centella asiatica seeds germinated when exposed to Control 68 different types of light. Many seeds do not require light to germinate but some do. Light from the Sun Red 73 contains ‘red light’ and ‘far red light’. Red light is Blue 38 absorbed by leaves. Far red light goes through leaves. An experiment was done to see how Far red 10 Ocimum americanum seeds germinated when Dark 4

exposed to sequences of ‘red light’ and ‘far red light’. a What was the effect of ‘red light’ and ‘far red light’ on germination? b Explain why this may be an advantage to the seeds.

I can… ● explain why seeds and plants need certain resources ● explain why seeds may only germinate at certain times.