Answer:
Positive
Explanation:
Hydrotropism is how a plant responds to water in a growing way. Positive means towards and negative means away. Roots grow toward the source of moisture, making that relationship positive.
Answer:
The mutations occur at a rate of 0.56 base changes every 1 billion years. If this rate stays consistent, the mutation rate can be used to determine when different lineages of a particular species split
oxygen flow is low and his lungs do not have a lot of capacity
(1)
For unicellular organisms, cell division is important for the reproduction of the population, Unicellular organism mainly use cell division, also called binary fission, for pollution growth. This is because unicellular organisms are only composed of one cell.
Multicellular organisms use cell division for growth and reproduction. Cell division causes increase in the number of cells composing the organism hence its growth in size. Cell division is also used to create gametes that are used in reproduction by fertilization.
(2)
Even in fully developed organisms, cell division is important in tissue repair. In tissue homeostasis, there is a balanced rate of cell division and cell death . An example in muscles. Due to the stress experienced by muscle cells, they usually have a lower life span and therefore the damaged cells are often replaced with new ones by cell division. This prevents tissue wastage.
(3)
Growth factors signal the growth of a cell. They usually bind receptors on the cell surface and indicate how the cell should grow and divide base don environmental stimuli. An example is during regular exercises. Growth factors indicate that the muscle cells should divide regularly and grow bigger to accommodate the higher stress in the muscles from the workout. This is how your muscles grow bigger and stronger with more exercise.
(4)
Differentiation of cells occurs through the silencing of some gene allowing the cell to produce particular proteins (and other biomolecules) that align with its functions in the body. This especially critical in multicellular organisms. An example is that while al the cells in your body have the same DNA, some cells differentiate into liver cells while others into lungs, stomach, heart, and etcetera.
Learn More:
For more on cell division check out;
brainly.com/question/4365207
brainly.com/question/11266913
#LearnWithBrainly
