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- examples of plant organs that unspecialised cells can differentiate into if the hormone conditions are right
- leaves, roots and flowers
- what are auxins
- chemicals that control growth near the tips of the shoots and roots
- heterozygote
- when two alleles of a pair are different
- what happens to a plant when you add rooting powder?
- it contains auxins and the plant will grow roots rapidly and start growing as new plants
- roots are....
- negatively phototropic
- gametes
- another name for the sex cells, sperms and eggs
- what do auxins do?
- they make shoots grow towards the light
- meristems
- contain unspecialised cells that are able to divide and form any cell type in the plant. But unlike human stem cells, these cells can divide to generate any type of cell for as long as the plant lives
- shoots are....
- positively phototropic
- genotype
- the alleles present
- the cells that the dividing meristems produce increase the plants what?
- heigh, girth and length
- what do cuttings of a plant contain?
- unspecialised meristem cells which can differentiate to make any cell
- chromosome
- a strand of genes
- where is meristem tissue found in a plant
- in the areas it is growing such as the roots and shoots
- examples of plant tissues that unspecialised cells can differentiate into if the hormone conditions are right
- xylem and phloem (the water and food transport tissues)
- what are proteins made by?
- ribosomes
- what is phototropism
- phototropism is movement in response to light in some parts of a plant like roots and shoots
- gene
- a section of DNA that determines a feature
- what does it mean for an embryonic stem cell to be undifferentiated?
- they're able to divide to produce any type of specialised cell
- how long are cells in humans undifferentiated?
- up till the eight cell stage
- what does DNA contain?
- all the instructions for how to grow and develop
- when a shoot is exposed to light, more auxin accumulates on the side that's in the shade, what does this make happen?
- this makes the cells grow faster on the shaded side, so the shoot bends toward the light
- where do adult humans have stem cells
- bone marrow, but they aren't as versatile as the stem cells in embryos-they can only differentiate into certain types of cell
- stem cell
- relatively undifferentiated cell
- what could embryonic stem cells be used for in sick people
- heart muscles cells for people with heart disease, nerve cells for people paralysed by spinal injuries
- what happens in negative phototropism?
- plants grow away from light
- clones
- genetically identical individuals
- meiosis
- cell division forming the sex cells
- the type of cell a stem cell differentiates into depends on what?
- which genes are active in that cell and so what proteins that cell produces
- what is DNA?
- a double helix of paired bases
- where does photosynthesis happen mainly
- in the leaves, so it's important for plant shoots, which will grow leaves, to grow toward the light
- mitosis
- cell division in growth
- phenotype
- the appearance of the organism
- why to plants need sunlight?
- for photosynthesis which makes them produce the food they need for energy and growth
- why do roots grow away from the light?
- because they can then absorb the water and nutrients the plants need for healthy growth
- what happens when the cells start to differentiat
- the embryo begins to develop tissues and organs
- what are the four bases of DNA?
- adenine, cytosine, guanine and thymine
- allele
- a different form of a gene
- in plants growth in height is mainly due to what?
- cell enlargement or elongation-cell division usually just happens in the tips of the roots and shoots
- what is differentiation
- the process of stem cells becoming specialised
- homozygote
- when two alleles of a pair are the same