Microtubules contribute to each of the following except a) mitotic spindles. b) filopodial structure. c) the human red blood cell disklike shape. d) orientation of plant cellulose microfibrils. e) intracellular transport.

Explanation:

The microtubules are made up of tubulin proteins and are hollow tubes that gives shape to the cell and organelle place in the cell. The movement of organelles occurs due to the transport function provided by the microtubules.  

Microtubules contribute to spindle apparatus involved at the time of cell division. The RBCs size is maintained by stiffness of microtubules. The microfibrils walls are arranged  parellely with cortical microtubules. The microtubules also function in intracellular transport of organelles and vesicles (membrane-bound). Thus, option b is correct.

Learn more: Microtubules

1.

2. link

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation:

i got something better   a catchphrase here it is

ahem  

ahem

what the squwock

explanation: