Asexual vs. Sexual Reproduction

Asexual Reproduction

Reproduction involving one parent, producing genetically identical offspring.

Sexual Reproduction

Reproduction involving two parents, producing genetically diverse offspring.

Gametes

Sex cells (sperm and egg) involved in sexual reproduction.

Fertilization

The process of fusion between sperm and egg.

Clones

Genetically identical offspring produced in asexual reproduction.

Genetic Variation

Differences in DNA among individuals; increased in sexual reproduction.

External Fertilization

Fertilization that occurs outside the female's body.

Internal Fertilization

Fertilization that occurs inside the female's body.

Diploid

Cells containing two sets of chromosomes (2n).

Haploid

Cells containing one set of chromosomes (n).

Somatic Cells

Non-sex body cells that are diploid.

Homologous Chromosomes

Chromosome pairs in somatic cells that are genetically similar.

Mitosis

Process that produces identical somatic cells for growth or repair.

Meiosis

Process that produces gametes and reduces chromosome number.

Binary Fission

A type of asexual reproduction resulting in two identical cells.

Multiple Fission

A type of asexual reproduction resulting in more than two identical cells.

Fragmentation

Asexual reproduction method where the parent breaks into pieces, each growing into new organisms.

Budding

Asexual reproduction where a new organism grows out of the parent.

Spore Formation

Asexual reproduction where the parent produces spores that can grow into new organisms.

Vegetative Propagation

Asexual reproduction where new plants grow from parts of the parent.

Zygote

The fertilized egg formed from the fusion of sperm and egg.

Crossing Over

The exchange of genetic material between homologous chromosomes during meiosis.

Independent Assortment

Random separation of homologous chromosomes during gamete formation.

Random Fertilization

The random union of any sperm with any egg, increasing genetic diversity.

Daphnia

An example of an organism that alternates between asexual and sexual reproduction.

Amoeba

A unicellular organism that reproduces asexually by fission.

Hydra

A simple animal that can reproduce asexually through budding.

Sponge

A simple organism that can reproduce asexually via budding or fragmentation.

Potato tuber

An example of vegetative propagation in plants.

Mitosis purpose

Growth and repair in multicellular organisms.

Meiosis outcome

Produces four haploid gametes from one germ cell.

Polar bodies

Nonfunctional cells produced during female meiosis.

Adaptive advantage of sexual reproduction

Increases genetic variation, improving survival in changing environments.

Genetic Stability

Maintained through meiosis, preventing chromosome number doubling.

Advantages of Asexual Reproduction

Rapid population growth and efficiency in stable environments.

Disadvantages of Asexual Reproduction

Low genetic variation and poor adaptation to environmental changes.

Advantages of Sexual Reproduction

Increase in genetic variation leading to better adaptation.

Disadvantages of Sexual Reproduction

Generally slower process and requires more energy for gamete production.

Environmental Trigger for Reproductive Mode Change

Changes in conditions may prompt some organisms to switch between asexual and sexual reproduction.

Fungi Asexual Reproduction Examples

Molds and mushrooms reproduce asexually mainly via spore formation.

Reproductive Strategies in Daphnia

Asexual reproduction in spring and sexual reproduction in harsh conditions (winter).

Chromosome pairs in Humans

23 pairs of chromosomes (2n = 46).

Asexual vs. Sexual Reproduction Key Takeaway

Asexual reproduction is faster with no variation; sexual reproduction is slower but increases genetic diversity.

Asexual Reproduction Examples

Common in unicellular organisms, simple animals, fungi, and some plants.

Genetic Outcome of Fertilization

Combines haploid sperm and egg to form a diploid zygote.

Chromosome Reduction Purpose in Meiosis

To ensure genetic stability across generations by reducing chromosome number.

Two divisions of Meiosis

Meiosis I (reduction division) and Meiosis II (chromatid separation).

Meiosis in Male Results

One germ cell produces four functional sperm of equal size.

Meiosis in Female Results

One germ cell produces one functional egg and three polar bodies.

Mitosis and Meiosis: Key Difference

Mitosis maintains chromosome number; meiosis reduces it for gamete formation.

Genetic Variation Sources

Crossing over, independent assortment, and random fertilization contribute to genetic diversity.

AP Biology Key Concept

Sexual reproduction increases genetic variation and maintains chromosome number.

Asexual Reproduction Efficiency

Fast and efficient, especially in stable environments.

Sexual Reproduction Organisms

Common in complex organisms such as plants and animals.

Cell Types in Organisms

Somatic cells (diploid) and gametes (haploid).

Types of Asexual Reproduction

Fission, fragmentation, budding, spore formation, and vegetative propagation.

Key Takeaway for AP Biology

Sexual reproduction enhances survival and evolution through genetic diversity.

Variations in Offspring

Increased by sexual reproduction due to genetic combinations from two parents.

Disadvantages of External Fertilization

Many gametes are wasted, resulting in low offspring survival rates.

Fertilization Types Overview

Two primary types: external and internal fertilization.

Function of Spores

Spores are a form of asexual reproduction that can grow into new organisms.

Role of DNA in Mitosis

DNA is copied and divided equally to produce identical daughter cells.

Asexual Reproduction Advantages

Allows for rapid population growth without the need for partners.

Sexual Reproduction Mechanism

Involves gametes and fertilization to create genetic combinations.

Specialization in Reproductive Cells

Gametes are specialized for sexual reproduction, whereas somatic cells are not.

Organism Strategies in Reproduction

Many organisms can switch between asexual and sexual reproduction based on environmental cues.

Key Processes in Meiosis

Meiosis I leads to the reduction of chromosomes; Meiosis II separates chromatids.

Genetic Diversity Importance

Essential for the adaptability and survival of species in changing environments.

Asexual Reproduction in Simple Organisms

Often found in unicellular organisms and some invertebrates.

Chromosomes in Fruit Flies

4 pairs (2n = 8) indicating lower complexity compared to humans.