Unit 8 Lesson 2: Genetic Variation from Meiosis Flashcards
The passing of genetic information from one generation to the next is called
heredity.
heredity
the passing of genetic material found in chromosomes from parents to offspring
This genetic material is passed to offspring from each parent in the form of
alleles, which are alternative forms of a gene.
. However, the genes may not be an exact mix of the parents’ alleles because of
variations
inheritable genetic variations
changes in genetic material that can be passed to offspring
importance of inheritable genetic variations
These inheritable genetic variations create differences between organisms in a species and contribute to diversity.
How does inheritable genetic variations happen
There are many causes of genetic variation, but one of them happens during meiosis.
What is DNA
DNA (deoxyribonucleic acid) is a molecule that contains the instructions that make each organism unique.
When is DNA passed down and does every living cell contain DNA
Every living cell contains DNA, and the DNA is passed along from adults to offspring during the process of reproduction.
Some organisms replicate asexually. How do organisms like bacteria repliacate
These organisms include bacteria that can produce offspring through cell division.
. Asexual reproduction can also include a process called budding, whats thay
Asexual reproduction can also include a process called budding, where a new organism starts growing out of the body of the parent organism.
What is the realstionship between the DNA of the parents and offspring of asexual reproduction
As a result, in both forms of asexual reproduction, offspring have the same DNA as the parent.
What is the realstionship between the DNA of the parents and offspring of sexual reproduction
Other organisms replicate sexually. These offspring inherit DNA from both parents, resulting in new, unique combinations of traits.
Genetic variation can be a result of meiosis. What is Meiosis
Meiosis is a type of cell division that in two phases will result in four daughter cells, each with half the number of chromosomes of the parent cell.
Why is Meiosis is important for sexual reproduction
Meiosis is important for sexual reproduction because it produces gametes
gametes
sex cells, which are egg and sperm cells
How much chromosomes do Gametes have
. Gametes have half the number of chromosomes that body cells contain. They are haploid
haploid
the state of having half the number of chromosomes as compared to body cells. “half the chromosomes.”
How does a gamete create pairs o chromoomes
A gamete unites with another of the opposite sex to create pairs of chromosomes.
Why is it important to have sex cells that only have half the number of chromosomes? Most human cells contain 46 chromosomes found in pairs. What would happen If two body cells, each containing the full number of chromosomes, are joined together?
If two body cells, each containing the full number of chromosomes, are joined together, the resulting cell would have 92 chromosomes instead of the usual 46. This would result in an entirely different organism!
Why is it important to have sex cells that only have half the number of chromosomes? Most human cells contain 46 chromosomes found in pairs.
However, if a sperm cell only has 23 chromosomes (haploid) and the egg cell also has 23 , when they join, the offspring’s cells will have: 23+23=46 chromosomes.
Meiosis is a two-phase process:
Phase I and Phase II.
What occurs during Phase I of Meiosis
Genetic variation occurs in Phase I.
What happens during Phase II of meiosis
Phase II is an equal division of the chromosomes because the set of chromosomes in each daughter cell are just divided into two identical cells.