Chapter 9: Reproduction

2 Types of Reproduction Sexual and Asexual They both need to obtain energy, grow, develop, exchange materials with the environment and REPRODUCE 2 Types of Reproduction

Why is Reproduction important? Without reproduction life on Earth could not continue Why is Reproduction important?

Asexual Reproduction Binary Fission Budding Fragmentation Parthenogenesis Asexual Reproduction

Binary Fission Happens in Bacteria and protists The parent cell divided into 2 Cell division occurs 1 parent cell= 2 daughter cells Binary Fission

Budding Happens in Sponges, Jelly Fish and Yeast The parent grows a small bud or branch on its body When the bud is large enough to live by itself it separates and the small section of cytoplasm pinches off Budding

Fragmentation Happens in Planarians Flatworms and Fungi The organism attaches itself and divides into two. Eventually the other half starts to grow Fragmentation

Females produce eggs that develop without being fertilized This is only type of asexual reproduction that produces offspring with genetic variation Honeybees Parthenogenesis

Advantages to Asexual Reproduction It is simple because it takes place quickly and easily. The organisms do not have to find a mate It is efficient because one individual can produce large numbers of offspring in a short time Advantages to Asexual Reproduction

Disadvantages to Asexual Reproduction Offspring do not have much genetic variation because they inherit DNA from only one parent In 1940 and 1950s disease destroyed most of banana crops because bananas reproduce asexually. Disadvantages to Asexual Reproduction

Sexual Reproduction External fertilization Self fertilization Internal Fertilization Conjunction Sexual Reproduction

Sexual Reproduction Reproduce through meiosis Gamete is the egg or sperm that is specialized for reproduction Male and Female Gametes join to make a zygote Zygote is a fertilized egg Sexual Reproduction

Internal and External Fertilization External happens in water and usually by fish Internal happens in mammals when the offspring develop inside the mothers body after fertilization Internal and External Fertilization

Organisms with both male and female sexual organs can produce sperm cells that fertilize their own eggs This happens in self pollinating plant Zygote is the half the DNA from the mom and Half from the dad Self Fertilization

Conjugation This happens with a Pilus- Bridge There is a dinar and receiver of DNA Conjugation

Why Sexual Reproduction is Important It takes time but it increases genetic variation Genetic diversity helps species survive changes in the environment Why Sexual Reproduction is Important

Plant Reproduction

Sexually and Asexually Plants Reproduce

Asexual Plant Reproduction Vegetable Propagation—when plants produce offspring from non reproductive tissues such as leaves, stems and roots Different ways Tubers and Bulbs Runners and Rhizomes Fragmentation Asexual Plant Reproduction

Sexual: Tubers and Bulbs Large fleshy underground stems that store nutrients and give rise to new plants Potato's and sweet potato's are Tubers Onions, Daffodils and tulips are Bulbs Sexual: Tubers and Bulbs

Asexual: Runners and Rhizomes Specialized stems that grow off an adult plant Runners are above ground Rhizomes are below ground Asexual: Runners and Rhizomes

Asexual: Fragmentation A piece of a leaf or stem breaks off the parent plant and falls to the ground Cuttings- when you cut a plant and wait for it to grow roots Asexual: Fragmentation

Plants: Sexual Reproduction Water Pollen Seeds Plants: Sexual Reproduction

Sexual Reproduction: water Water helps plants reproduce sexually Rainfall, streams and puddles help gametes travel from one plant to another The reproductive gamete travels as a spore A spore is a single reproductive Cell or gamete protected by a hard watertight covering Sexual Reproduction: water

Sexual Reproduction Pollen Pollen is a grain in a dry structure that hold a sperm cell in a tube cell Pollen is carried by wind, water or animals Pollination occurs when such a pollen grain attaches to an egg and releases its sperm Sexual Reproduction Pollen

Sexual Reproduction: Seeds Seeds are structures that enclose a plants embryo and stored food in a protective coat An embryo is the immature form of an organism that has the potential to grow and develop Sexual Reproduction: Seeds

Sexual Reproduction: plants Angiosperms Gymnosperms Sexual Reproduction: plants

Pine Trees were the first to reproduce using pollen and seeds Conifers are cone bearing plants During reproduction male cones release large amounts of pollen into the air and fertilize the egg Eggs develop into embryos and a seed coat Gymnosperms

Flowers Male and female reproductive structures are located in the same flower The reproductive organ of an angiosperm is its flower Angiosperms

Life Cycle of the Cherry Tree Meiosis Pollination Fertilization Seeds and Fruit Life Cycle of the Cherry Tree

Story of winner Reproduction

Female Reproductive System Fallopian Tubes-sites of fertilization Uterus becomes the womb Cervix is the base of the uterus Cervix connects the uterus to the vagina Male deposits sperm in the vagina Vagina is the birth canal Female Reproductive System

Male Reproductive System Main reproductive organ is the testis The urethra is a tube-like channel that goes through the penis and opens on the penis tip Male Reproductive System

The production of offspring includes sexual intercourse, fertilization, pregnancy and birth Human Reproduction

When and where does fertilization occur? When one sperm penetrates a mature egg. When and where does fertilization occur?

Fertilization After 24 hours of fertilization the egg begins to divide The embryo continues to divide rapidly as it enters the uterus After a week the embryo attaches itself to the uterus Fertilization

Pregnancy Nine months 3 trimesters 12 weeks for each trimester The embryo and the uterus contribute new cells to a new organ called the placenta The placenta is an organ filled with blood vessels that supply the embryo with oxygen and nutrients Umbilical cord is a long tube that encloses blood vessels Pregnancy

Umbilical cord is attached to the embryo at a small opening in its abdomen called the umbilicus A fetus is a developing human from 8-12 weeks of pregnancy Pregnancy