asexual and sexual reproduction subtitle: how new generations form

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Asexual and Sexual Reproduction Subtitle: how new generations form

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Page 1: Asexual and Sexual Reproduction Subtitle: how new generations form

Asexual and Sexual Reproduction

Subtitle: how new generations form

Page 2: Asexual and Sexual Reproduction Subtitle: how new generations form

Asexual Reproduction

Formation of new individuals from a single individual – one parent

Page 3: Asexual and Sexual Reproduction Subtitle: how new generations form

Asexual Reproduction

There are several ways asexual reproduction can occur including:– Binary fission– Budding– Mitosis

• Primary form of reproduction for single celled organisms like bacteria.

• Many plants reproduce asexually as well.

• Asexual offspring (children) are identical to their parent.

Page 4: Asexual and Sexual Reproduction Subtitle: how new generations form

Binary Fission

• In binary fission the parent organism is replaced by two daughter organisms, because it literally divides in two.

• Both prokaryotes and eukaryotes reproduce asexually through

binary fission

Page 5: Asexual and Sexual Reproduction Subtitle: how new generations form

Prokaryotic vs. Eukaryotic

Page 6: Asexual and Sexual Reproduction Subtitle: how new generations form

Budding• Some cells split by budding (for example

yeast), resulting in a 'mother' and 'daughter' cell.

• Potatoes, some flowers and spider plants reproduce by budding.– The offspring is smaller than the parent.

Page 7: Asexual and Sexual Reproduction Subtitle: how new generations form

Mitosis

• Mitosis is a process of cell division which results in two daughter cells from a single parent cell.

• The daughter cells are identical to each other and to the parent cell.

• It is asexual reproduction.

Page 8: Asexual and Sexual Reproduction Subtitle: how new generations form

Regeneration Process of renewal, restoration, and growth that

makes cells able to repair themselves after damage.

Page 9: Asexual and Sexual Reproduction Subtitle: how new generations form

Regeneration

• Every species is capable of regeneration, from bacteria to humans.

• Starfish are able to re-grow arms if they have been cut off. Lizzards are able to re-grow tails.

Page 10: Asexual and Sexual Reproduction Subtitle: how new generations form

Human Regeneration

All organisms, including humans, have the ability to regenerate something in the body. But the process is much more developed in lower organisms such as plants – mammals do regenerate skin, muscle, and blood. – other types of cells, such as those in the brain also

regenerate.

– researchers are actively working in this field to find ways to encourage the body to regenerate organs and limbs.

Page 11: Asexual and Sexual Reproduction Subtitle: how new generations form

Sexual Reproduction

Creation of a new organism by combining the genetic material of

two organisms.

Page 12: Asexual and Sexual Reproduction Subtitle: how new generations form

Sexual Reproduction

• Sexual reproduction is the process involving two parents. – Their genetic material is combined to produce

a new organism different from each parent.

• All mammals reproduce sexually. – Every person is unique. – Even brothers/sisters are often very different

from one another.

Page 13: Asexual and Sexual Reproduction Subtitle: how new generations form

Fraternal Twins

• Fraternal twins make up approximately 75% of the twin population and can be boy/boy, girl/girl, or boy/girl sets. Happen when Mom releases two eggs and different sperm fertilize each egg.

• They do not look any more alike than typical siblings.

Page 14: Asexual and Sexual Reproduction Subtitle: how new generations form

Maternal Twins

Occur when a single egg is fertilized which then divides into two separate embryos.

Page 15: Asexual and Sexual Reproduction Subtitle: how new generations form

Chromosomes

• With sexual reproduction, the offspring inherits half their chromosomes from each parent. – Half the chromosomes means not all traits of

a parent will be transferred to the offspring. More on that in the next section on inherited traits!

Page 16: Asexual and Sexual Reproduction Subtitle: how new generations form

Chromosomes

• Chromosomes are structures found within the nucleus of a cell.

• They contain all the genetic information in the form of genes.

Page 17: Asexual and Sexual Reproduction Subtitle: how new generations form

DNA

• DNA is a long chain formation found in the nucleus of a cell.

• It is shaped like a double-helix

• It contains all the genetic material

Page 18: Asexual and Sexual Reproduction Subtitle: how new generations form

Donor Cells for Sexual Reproduction

• Sperm are the reproductive cells of males.

• Eggs are the reproductive cells of females.– Sperm and egg cells are different from all

other cells in your body because they contain only half of your genetic information.

– 2 halves combine to make a whole new organism!

Page 19: Asexual and Sexual Reproduction Subtitle: how new generations form

Meiosis

One cell from each parent contributes genetic material to produce offspring.

– Results in 2 daughter cells

– Receives ½ of genetic material from each parent

– Produces sex cells

– You were produced by Meiosis!

Page 20: Asexual and Sexual Reproduction Subtitle: how new generations form

MeiosisIn the diagram, the parentcell duplicates it’s DNA thendivides. Will combine withanother parent to complete theProcess and each contributeHalf of the offspring’s DNA.