MEIOSIS & PLANT REPRODUCTION

DATE: Saturday, February 6, 2016

TIME: 2:15 PM

WEATHER CONDITIONS: At the time of observation, it was approximately 48˚F outside. There was a 0% chance of precipitation throughout the day, and the sky was light blue with clouds sprinkled throughout.There were 30.35 in. of atmospheric pressure. The average humidity was 26%. The wind speed at the time of observation was around 5 mph.  

CHANGES: There are little to no changes in the appearance of the tree. It still remains barren and lifeless.

MEIOSIS: 

1. Mitosis vs. Meiosis

Mitosis is the division of the cell's nucleus. The end result is the parent cell dividing into two daughter cells that contain identical genetic information. In mitosis, the homologs do not pair up. 

Meiosis is a type of cell division specific to reproduction. The parent cell divides twice, resulting in four daughter cells. Each of these cells only contain half of the genetic information in order to not have an overload of DNA, but this does result in the genetic information being different and randomized. In meiosis, the homologs pair up. 

PLANT REPRODUCTION:

1. Pistil: the ovule producing part of a flower; the ovary often supports a long style that is topped with a stigma; this is a female part
2. Stamen: the pollen producing part of a flower; usually has a thin filament supporting the anther; this is a male part
3. Petals: the parts of a flower that are colored; serve as the flower's shield from the environment; helps attract or repel specific pollinators
4. In flowering plant fertilization, a female gamete (the egg) joins with the male gamete (the sperm). After the carpel is pollinated, the pollen grain germinates and a pollen tube emerges and grows. The tube creates a path through the female tissue towards the ovary, and the pollen grain attaches itself to the stigma of the female reproductive structure. This causes the pollen tube to grow and eventually enter the ovule, which creates a micropyle. The micropyle bursts into the embryo sac, and the male gamete is able to enter. This begins the process of nuclear fission. In flowering plant pollination, pollen is moved from the stamen to the stigma. Stamens are a male part of a flower that produces the sticky powder called pollen. The pistil, the flower's female part, has a stigma at the top of it that is often sticky. Seeds are made in the ovule, which is at the base of the pistil. As long as the sticky powder (pollen) gets from where it's made in the stamen to the top of the stigma (its own stigma or a neighboring plant's), this plant is considered to be pollinated. 
5. Alternation of generations is the alternation of sexual and asexual phases of reproduction. It is very common in lower level plants such as algae, fungi, and mosses. The sexual phase is called the gametophyte, and it produces the gametes, or a haploid set of chromosomes. The asexual phase, or sporophyte, produces a diploid set of chromosomes. 

RESOURCES:

• http://chsweb.lr.k12.nj.us/psidelsky/plant_meiosis.htm
• http://www.diffen.com/difference/Meiosis_vs_Mitosis
• http://www.pbs.org/wgbh/nova/miracle/divi_text.html
• http://www.amnh.org/learn/biodiversity_counts/ident_help/Parts_Plants/parts_of_flower.htm
• http://biology.tutorvista.com/plant-kingdom/plant-fertilization.html
• http://www.mbgnet.net/bioplants/pollination.html
• http://www.britannica.com/science/alternation-of-generations