1. Passing it On
Topic 3: Biodiversity

2. After this Topic, I need to be able to:
Describe the types of asexual reproduction
Distinguish between sexual and asexual reproduction
Provide examples of organisms that show each type of reproduction
Describe zygote and embryo formation in plants and in animals

3. … Think about your parents… do you look like them?
How does reproduction allow for variation?
Not only do the physical traits of organisms vary, but the ways in which organisms reproduce show variation as well.

4. Heritable: Traits that are passed on from parent to offspring.
Passed on in genetic material

5. Reproductive Strategies:
Binary fission
Spores
Vegetative growth in plants
Budding
Sexual reproduction
Asexual Reproduction

6. Asexual Reproduction
Occurs when only one parent supplies the information to the offspring.
The genetic material of the offspring, and thus their inherited characteristics, are identical to those of the parent.

7. Common among:
Bacteria
Fungi

8. Advantages: No need for an organism to find a mate
Reproduction occurs quite rapidly
Offspring will be able to survive and reproduce as their parents did, as long as the environment does not change too much

9. How would the use of wind-borne seeds increase variation in plant species?
Figure 1.20

10. Write a different type of asexual reproduction in each square.
Binary fission
Asexual spores
Vegetative reproduction – asexual reproduction in plants
Budding
In each square:
Include 2 pieces of important information about the type of asexual reproduction
Include 1 example

11. Binary Fission, Spores, Vegetative Reproduction, Budding
In each square:
Include 2 pieces of important information about the type of asexual reproduction
Include 1 example

12. Binary Fission (AS) Cell division Steps:
The cell duplicates its contents, including it’s nucleus and other organelles
Division
Each new cell has a copy of genetic material and half of a cytoplasm
Offspring are identical!

14. What are the new cells referred to as?
“daughter cells”

15. Asexual Spores Common in fungi (mushrooms) Spores:
A single-celled reproductive structure from which an individual offspring develops plants, algae and fungi
Only one parent organism supplies the genetic material
Produced to ensure that at least some of them survive

16. Common examples: Fungi Algae Why do you think zoospores have flagella?
Chlamydomonas
Ulva
Why do you think zoospores have flagella?
Produce zoospores:
- Move using tail-like flagella.

18. Asexual Reproduction in Plants (Vegetative Growth)
Plants continue to grow throughout their lives
Meristem:
Growing tips on roots and stems that contain rapidly reproducing cells

19. Meristematic cells are able to make repairs to damaged roots, leaves, or the stem of the plant.
You can try this at home!
Cuttings from a parent stem may be used to produce new plants
that are clones
(exact copies) of their
parents.

21. Budding What is budding? (find the definition and write it down!)
A bud forms on an organism, grows, and eventually breaks away to become a new organism independent of the parent.

22. Common among:
Sea sponges
hydra

23. Sponge buds may remain attached to the parent which results in a colony. What advantage does the bud have by being attached to its parent?

24. Hydras are very small organisms that live in water
Hydras are very small organisms that live in water. Based on what you have learned about budding, describe what is happening in this picture.

25. Sexual Reproduction
Occurs when 2 parents supply genetic material to the offspring
Offspring will
NOT be exactly the same
have a combination of both parents characteristics
allows for VARIATION!
Takes a lot of energy – few offspring

26. The Best of Both Worlds
Many organisms are capable of both asexual and sexual reproduction
Ex: Rhizopus (mould)
Produce spores with both parents genetic information

27. Types of Sexual Reproduction
Notes on:
bacterial conjugation
animal reproduction,
and
flowering plant reproduction

29. http://www. sciencedaily. com/videos/6ede1a6561dcae63b529a554ba5f704c

30. Topic 4: Wearing Your Genes
Read pg. 37 paragraph #1
Genetics: the study of genes or heritable traits

31. Study this family portrait and look for the child’s traits that are:
the same as both parents
the same as one parent
intermediate characteristics (in between the traits of both parents)
different from both parents

32. Variation is only a benefit if it passed on to the next generation.
Heritability: info can be passed on from generation to generation
Colour of eyes
Non-heritable: gain something from your environment
Ex: muscles

33. 2 Kinds of Variations
Continuous variation : refers to a range of different forms of a characteristics
Have a defined form
Ex: range of hair colour
Discrete variation: either/or form of a characteristic
Not a set number or another
Ex: light  dark hair colour

34. Bring your hands together and interlock your fingers.
Which thumb is on top?
Now, do opposite.... Is it uncomfortable?
The way you put your hands together is a genetic trait!

35. To do: Pg. 38 “Observing Human Characteristics” Make a bar graph
#1-3 questions

36. Allele:
Is one of two or more forms of the DNA sequence in a particular gene

37. Inheritance Every animal has 2 alleles for every trait
1 from the mother, 1 from the father
Trait: a characteristic of an organism
Capital letter – dominant allele (Ex. B)
Lower case letter – recessive allele (Ex. b)
BB or bb– purebred animals
Bb – hybrid (also called carriers)

38. How can we figure out what allele is dominant?
By crossing 2 different purebred animals
Ex: You have a white female cat and a black male cat and all the kittens are black. Which color is dominant? Are these kittens still hybrids? Would the same the same results happen each time? Would a Bb & BB look the same?
The hidden traits (the b in Bb) are called recessive while the ones that we can see (B in Bb) are called dominant

39. Ex #2: Two hybrid cats mate. 3 kittens are black, 1 is white. Why?

40. Other Patterns of Inheritance

41. Incomplete Dominance
Note: the dominant/recessive pattern of inheritance does not always occur!
Ex: white purebred snapdragon is crossed with a red purebred snapdragon = What is the outcome?
PINK snapdragons!
Therefore both the white and red traits are dominant OR recessive!

42. An Assumption...
Many people connect the frequency of a characteristic with whether it is dominant or recessive. People often assume that if a trait is widespread (frequency) in a population, then it must be dominant.
However dominance and frequency are different. The frequency of a trait can vary from population to population.

43. Changing Our Genetic Information
Genetic information can be changed by factors in the environment and by random errors
These changes to DNA are called mutations
Mutagens: cause mutations
Ex: x-rays, UV rays, cosmic rays, chemicals
Mutations can have little or a lot of effect on an organism.
Can be beneficial or harmful!!!

44. Mutations can:
Cause cancer (uncontrolled dividing of cells)
Be passed on from parent to offspring
Are mutations always negative? Provide one examples of a positive mutation, and describe how it is beneficial.