REPRODUCTION

Disciplinary Core Ideas:

• In multicellular organisms individual cells grow and then divide via a process called mitosis, thereby allowing the organism to grow. The organism begins as a single cell (fertilized egg) that divides successively to produce many cells, with each parent cell passing identical genetic material (two variants of each chromosome pair) to both daughter cells.

• Cellular division and differentiation produce and maintain a complex organism, composed of systems of tissues and organs that work together to meet the needs of the whole organism.

• In sexual reproduction, chromosomes can sometimes swap sections during the process of meiosis (cell division), thereby creating new genetic combinations and thus more genetic variation. Although DNA replication is tightly regulated and remarkably accurate, errors do occur and result in mutations, which are also a source of genetic variation. Environmental factors can also cause mutations in genes, and viable mutations are inherited. 

Learning Expectation

The student is expected to use a model to illustrate the role of cellular division (mitosis) and differentiation in producing and maintaining complex organisms.

Iowa Core Standard Correlation:

HS-LS1-4.  Use a model to illustrate the role of cellular division (mitosis) and differentiation in producing and maintaining complex organisms.

HS-LS3-2.  Make and defend a claim based on evidence that inheritable genetic variations may result from (1) new genetic combinations through meiosis, (2) viable errors occurring during replication, and/or (3) mutations caused by environmental factors. 

Minds on Biology (MOBs)

MOB 1:  Significance of Reproduction *

MOB 2: Asexual v. Sexual Reproduction *

MOB 3: Reproductive Methods and Strategies

MOB 4: Sexual Selection

MOB 5:  Why Sex? (In Class) *

MOB 6: Critical Reading *

MOB 7: Pollinators and Flowering (In Class) *

MOB 8: Embryo Growth

MOB 9:  Cell Differentiation

MOB 10: The Cell Cycle

MOB 11: Meiosis

MOB 12: Mitosis v. Meiosis

MOB 13: Cancer *

MOB 14:  Scientific Arguments *

MOB 15: Brine Shrimp Reproduction *

MOB 16: ACT Prep-Yellow Fever *

MOB 17: ACT Prep--Bacteria Mutation*

MOB 18:  Jeopardy

*= denotes graded

Objectives:

(a.) Define reproduction and explain the importance (significance) of reproduction in nature.

(b.) Summarize the advantages and disadvantages of various reproductive strategies (R v. K), reproductive modes (asexual v. sexual reproduction) and fertilization methods (external v. internal).

(c.) Write and interpret a scientific argument (C-E-R) to determine what environmental factors impact reproductive outcomes.

(d.) Identify the reproductive methods and strategies employed by various organisms.

(e.) Write and interpret a scientific argument (C-E-R) to determine the impact sexual selection has on a population.

(f.) Summarize and model fertilization in humans and flowering plants.

Links/Sources:

• Section 12-1, 38-1, 17.5

• (Interactive) Asexual v. Sexual Reproduction

• BBC Private Life of Plants: Flowering

• (Link) Sex and genetic shuffling

• Modes of Reproduction

• No Sex Please, We're Parthenogenetic (Nat Geo)

Objectives:

(g.) Summarize and model the sequence of embryonic cell differentiation using the terms: morula, cleavage, blastocyst, implantation, embryo and gastrulation. 

(h.) Describe the importance of cell differentiation.

Links/Sources:

• Sections 38.2 - 38.3, 38.8

• Embryo Growth

Objectives:

(i.) Summarize and model the steps and importance of the mitotic cell cycle.

(j.) Summarize and model the importance of meiosis and the contribution crossing over makes to the genetic diversity of an organism.

Links/Sources:

• Sections 11.1, 12.2, 12.4

• Control of the Cell Cycle Game

• Mitosis, Meiosis and Fertilization

• Dragon Meiosis (Concord Interactive)

Objectives:

(j.) Summarize and model how cancer develops and spreads.

Links/Sources:

• Section 11.5

• PBS Nova: How Cancer Grows