How to Make More Cells Neosho School District

How to Make More Cells Neosho School District

Nucleus Most plant and animal cells have a nucleus. Inside this nucleus are instructions on how to be that kind of cell and how to make more cells.

DNA Those instructions are called genetic material. Deoxyribonucleic Acid (DNA) is that genetic material in your cells that carries info. From parent to offspring (new cell).

Chromosome Cellular structures that occur in pairs (23 pr. In humans— 46 total) Carry hereditary information in units called genes

Gene Segment of a chromosome that has information for a trait Thousands of genes on a chromosome

Reproduction is the process of producing offspring Reproduction can occur asexually or sexually

Asexual Reproduction involving only one parent body cell

Asexual Offspring (daughter cell) is identical to parent cell Same genetic information in parent cell is copied and passed on to daughter cell

Types of Asexual Reproduction Budding: Offspring grows out of the parent organism identical to the parent Examples: Hydra, yeast, and Some Plants

Hydra

Yeast

Some Plant Cells

Types of Asexual Reproduction Binary Fission (aka Mitosis): Cell copies itself and divides in two Examples: Single cell organisms, your body cells

Mitosis • Prophase – 1 st Phase of Mitosis – Chromosomes form and duplicate – Centrioles begin to form the spindle – DNA strands attach to the chromosomes at the centromere (the center of the chromosomes) – Nucleolus disappears – Nuclear Envelope breaks apart

Mitosis • Metaphase – 2 nd Phase of Mitosis – The centromeres line up across the center of the cell – The spindle fiber connect the centromeres to the 2 poles of the spindle

Mitosis • Anaphase – 3 rd Phase of Mitosis – Chromosomes are divided at the centromere and separated into two groups at the poles of the spindle

Mitosis • Telophase – 4 th Phase of Mitosis – Chromosomes spread out into chromatin – Nuclear envelope forms – The spindle breaks apart – Nucleolus forms in the nucleus in each of the daughter cells – Cell Membrane begins to pinch in

Asexual Reproduction 46 1 Gene Set DNA Duplicates 2 Gene Sets 1 Gene Set 46 92 Cell Divides 1 Gene Set 46

Cell Cycle

Cell Cycle • Interphase – The 1 st phase of the Cell Cycle – The cell spends most of its time in this stage.

Cell Cycle • Mitosis – The 2 nd Stage of the Cell Cycle – Prophase, Anaphase, Metaphase, and Telophase occur here.

Cell Cycle • Cytokinesis – The 3 rd Phase of the Cell Cycle – The cell membrane grows together and the cell split in two (animal cell) – The cell plate grows from the middle of the cell to the outer edges and the cell splits in two (plant cell)

Sexual Reproduction involving two organisms contributing genes to form a new individual Genetic material from both parents is passed on and combined to form a new gene set for the new organism

Sexual Reproduction Offspring not identical to either parent due to combining of different genetic codes contained in each of the sex cells (23 chromosomes) which are produced by meiosis

Sexual Reproduction Two sex cells are involved The two sex cells each have one-half of a set of genes that are passed from parent to offspring ½ set + ½ set = 1 set

Sexual Reproduction ½ Gene Set 23 23 Cells Combine 46 1 Gene Set

Fertilization Union of a sperm cell with an egg cell

External Fertilization Egg and sperm meet outside the body of the organism Examples: Fish, frogs, toads

Internal Fertilization Egg and sperm meet inside the body of the organism Examples: Mammals, salamanders, reptiles, birds

What does DNA Look Like? Double Helix: two chains that spiral Think of a twisted ladder or spiral staircase.

DNA carries information from parent to offspring. That offspring can be another single cell or a whole new organism. We will focus on just the cells.

Application • Write a diary entry from the perspective of a teenage hydra that just learned it will grow up to be just like its mom because it has the exact same genetic information. Diary entry should be at least 150 words.

• Dear Diary, I just found out that I was created by a process called budding. This means that I was created by………………. and that I will grow up to be just like my mom!!!