Reproduction Chapter 2 Lesson 1

Today you will recognize that information is passed from parent to offspring during reproduction.

Sexual Reproduction Living things come from other living things. Every living thing comes from a parent organism through the process of reproduction. Sexual reproduction is the production of a new organism from two parents. A sperm cell from a male and an egg cell from a female join into a single unit in a process called fertilization. The new individual will receive some characteristics, or traits, from each parent. A trait is any characteristic of a living thing.

Asexual Reproduction Asexual reproduction is the production of a new organism from a single parent. This produces a new offspring that has the same genetic information as the parent. The offspring are identical to the original parent. You can find organisms that reproduce asexually in all six kingdoms. Bacteria, most fungi, many plants, jellyfish, coral, and worms, some lizards, fish, and insects can reproduce this way.

Quick check What are the two types of reproduction? How is genetic material transferred from parent to offspring?

Types of Asexual Reproduction Splitting – Most unicellular protists and bacteria reproduce by splitting into two cells. Before splitting the organism first makes a copy of its own genetic material. Some bacteria can divide into two new organisms every 10 to 20 minutes.

Budding Budding – Sponges, some fungi, and cnidarians reproduce through budding. During budding a small part of the parent’s body grows into a tiny and complete version of the parent. Sometimes the bud breaks off and continues growing and sometimes it stays connected and continues growing. (Coral)

Types of Asexual Reproduction in Animals Some species of fish, insects, frogs, and lizards go through asexual reproduction in a different way. The females lay eggs that are sometimes fertilized and sometimes not. In that case the eggs just develop into a new animal without fertilization. Queen honeybees lay eggs. Some are fertilized and others are not. The fertilized eggs develop into females, or worker bees. The unfertilized eggs become males or drone bees.

Propagation Plants can undergo a form of asexual reproduction. Vegetative propagation is asexual reproduction in plants that produces new plants from leaves, roots, or stems. Many plants commonly reproduce like this by producing runners. Runners are plant stems that lie on or under the ground and sprout up as new plants. Strawberries, most grasses, aspen trees, and ferns use runners to reproduce.

Advantages Asexual Reproduction Sexual Reproduction Convenient Can live in isolation Tend to be well suited to environment Variety in a species Gives rise to offspring that may be better suited Offspring is not identical to parent

Quick Check How do sexual and asexual reproduction differ? Closure: What type of reproduction will we see in our experiments?