130 likes | 444 Views
Multicellular Organisms. National 4 Unit 2. Germination. For seeds to germinate (i.e. grow), they need particular conditions: Water Oxygen Warmth. Propagation. Propagation is the process by which a grower increases the yield of a particular plant. There are two methods of propagation:
E N D
Multicellular Organisms National 4 Unit 2
Germination For seeds to germinate (i.e. grow), they need particular conditions: Water Oxygen Warmth
Propagation Propagation is the process by which a grower increases the yield of a particular plant. There are two methods of propagation: Vegetative Artificial
VegetativePropagation Vegetative propagation is a form of asexual reproduction in plants. This means that the offspring formed through this type of propagation will be identical to the parent plant (a clone). Why is this important?
Vegetative Propagation Examples: Bulbs are an example of vegetative propagation. An example of a bulb is an onion. They act as a food store for the plant to grow from the bud. Bud (Will grow Into a new plant)
Vegetative Propagation Examples: Tubers are another example of vegetative propagationwhich act as a food store. An example of a tuber is a potato.
Vegetative Propagation Some plants, like the strawberry plant, produce miniature plantscalled plantletsattached to the parent. The plantlets obtain food from the parent plant until they have produced roots and can absorb water and minerals from the soil.
Growing Plants Some plants can be sheltered to allow us to control the conditions they are grown in and protect them. Polythene tunnel Greenhouse
Genetics We all receive one allele for each characteristic from our mother and one from our father The allele that is expressed in the phenotype (the physical appearance) is known as the dominant allele and the other as the recessive allele The dominant allele is represented by a capital letter and the recessive by a lower case.
Genetics If the alleles that an individual receive from their parent are the same, they are said to be homozygous. If the alleles from each parent are different then they are said to be heterozygous.
Genetics For example: Purple petals (P) is dominant to yellow petals (p). If a true-breeding (homozygous) purple plant is crossed with a yellow plant, the offspring will all be yellow.
Insulin Insulin is a hormone that allows our body cells to absorb glucose from our blood. Special cells (called beta cells) in the pancreas produce insulin and release it into the bloodstream. When we eat a meal, the level of glucose in our blood increases. This leads to a rise in insulin.
Insulin On occasion, the pancreas may not produce enough insulin or our body cells may stop responding to it. This leads to diabetes and means we cannot control the amount of glucose in our blood.