Reproduction methods

Outline of the day

1. Turn in your lab reports at the front– More than 10 minutes late = bad

2. Any questions on last week’s lab?

3. Quiz

4. Introduction to the lab

5. Lab!

6. Check out• Get a stamp• Make sure I mark you down for attendance

Quiz

• Ends 8 minutes after it’s started

– Ends at: ____

Lab this week!

• Exploring reproduction!– Asexual vs. sexual reproduction– Seeing various organisms and their

reproductive structures– Looking at the spread of STDs– Analyzing your bacterial plates from last time

Sex: Yes or No?

• No: Asexual– Reproduction without gametes– One parent

• Yes: Sexual– Reproduction with gametes– Two parents

What types of asexual reproduction are there?

• Fission– Single celled organisms only– One cell divides into two or more cells

Image PD from NIH, obtained from http://en.wikipedia.org/wiki/Image:EscherichiaColi_NIAID.jpg

Asexual reproduction• Budding

– Small outgrowth of parent– E.g. hydra

• Gemmulation– Formation of a new individual from an

aggregation of cells surrounded by a protective layer

– E.g. freshwater sponge

Missing image:Hydra budding

Missing image:Sponge with gemmule.

Asexual reproduction, ctd.• Fragmentation /

regeneration– animal breaking into 2 or

more parts, each capable of becoming a whole organism

– E.g. brittle star or sea star

Missing image:Sea star or brittle star

regenerating a lost limb.

Sea star regernating limb - cc by ancnd by Boogies with Fish http://flickr.com/photos/boogieswithfish/434421599/

Asexual reproduction, ctd.• Parthenogenesis

– Development from an unfertilized egg

– E.g. aphids

aphid - cc ancnd by teejaybee at http://flickr.com/photos/teejaybee/881035777/

Missing image:Aphid life cycle.

• Production of offspring formed by union of gametes from two genetically different parents– Hickman, 1988

Sexual reproduction

black beetle sex - cca by photogirl7 at http://flickr.com/photos/kitkaphotogirl/861090078/dragonfly sex - cca by sahua at http://flickr.com/photos/sahua/234017059/red beetle sex - ccncd by Thundershead at http://flickr.com/photos/thundershead/407886828/

Types of sexual reproduction

• Biparental– Separate male and female individuals

produce male and female gametes

• Hermaphroditic– Single individual can produce both male and

female gametes

Types of hermaphrodites• Simultaneous hermaphrodites

– Individuals can produce both male and female gametes at the same time

• (sometimes can self-fertilize)

• Sequential hermaphrodites – Individuals can produce either male or female

gametes, but not both, at any given time– But can switch sex

• Clownfish (aka Nemo!)– Largest individual is a female– Second largest is a reproductive male– Most of the others in the group are non-

reproductive– Nemo’s mom disappeared … what should have

happened?

Missing image:Picture of Nemo

Lets break for our exercise!

• We’re going to look at the transmission of disease between individuals

• We’ll do this using a model system (test tubes!)– There are a number of bottles on the table; one of them is infected with a disease

– We’ll have “contact” between individuals to spread the disease, then at the end see who’s infected

• We’ll do this two times

First time!

1. Get a test tube, a transfer pipette, and a bottle2. Fill your test tube half-full with liquid from your

bottle (using the pipette)3. Find one person, and have “contact” with them

• Transfer one pipette’s worth of fluid into their tube, while they simultaneously do the same

4. Find another person and have “contact” with them

5. Add the indicator• Yellow / clear = not infected• Red = infected!

6. Who was infected?

Second time!1. Get a NEW test tube, a NEW transfer pipette, and a

NEW bottle2. Fill your test tube half-full with liquid from your bottle

(using the pipette)3. Find one person, and have “contact” with them

• Transfer one pipette’s worth of fluid into their tube, while they simultaneously do the same

4. Find another person and have “contact” with them5. Find another person and have “contact” with them6. Find another person and have “contact” with them7. Add the indicator

• Yellow / clear = not infected• Red = infected!

8. Who was infected?

Plant reproduction!

Vascular, seed producing plants

Angiosperms (flowering)Non-flowering(Gymnosperms)

All images by Marc Perkins except bonzai conifer: by andrew k at http://flickr.com/photos/andrew_k/507635592/

Not all plants produce seeds• Ferns (Pterophyta) and fern allies

– No seeds – only produce spores• Requires water to have gametes combine

– Has vascular tissue

Sporophyte (2n)

Sporophytes make spores (1n) on the bottom of the leaves

Gametophytes (1n) grow from spores, make gametes

fern sori - ccancnd by Squash713 at http://flickr.com/photos/benhenderson/442016333/ferns - ccancnd by mr_wahlee at http://flickr.com/photos/mr_wahlee/653329699/Fern prothallus PD by Velela at http://en.wikipedia.org/wiki/Image:Dixonia_prothallus.jpg

Not all plants are vascular• Mosses, hornworts, &

liverworts– (Bryophyta, Anthocertophyta,

& Hepaticophyta)– The “plant” as we know it is

actually a gameteophyte• It’s haploid (1n) – equivalent to

our sperm and eggs!

– Lack conducting vessels (no true roots / stems)

Sporophytes (2n)

Gametophytes (1n)Photo by Marc Perkins

Notes on the slides

• Paramecium – a single-celled protist– Reproduces via fission (mitosis)

• Volvox – a colonial protist– Made up of hundreds of cells– Reproduces either seuxally or asexually

• Rhizopus– A type of fungus (zygomycete)– Reproduces either sexually (via zygospores, which are created

when two fungal cells join) or asexually (via a sporangium)• Spores are released into the environment to be distributed

• Club fungi – a fungus– Sexually reproduces by fusion of fungal cells– Creates a fruiting body that produces spores

• AKA: Mushroom!

Volvox aureus

• Small green dots are cells of the colony

• Large green circles are daughter colonies

CC image: http://flickr.com/photos/algreer/17087738/

Rhizopus

CC image from: http://flickr.com/photos/jennaw/254291825/

CC image from: http://flickr.com/photos/jennaw/254292087/

• Sporangia

• Zygospore CC image from: http://flickr.com/photos/jennaw/254291912/

Before you leave

• Clean up your work area

• Show me your lab report so I can stamp it– Need to have all data fields filled in– Complete at home and then turn in at the beginning of

next lab

• Remember that we’ll have a quiz at the beginning of the next class– 6-7 questions on today’s lab– 3-4 questions on the lab we’ll do next week

Notes for the instructor:

• Add any relevant cleanup instructions to the final slide (that slide is a generic one I’m adding to each presentation).

• I wanted to add a bit more flavor and detail to this week’s lab (as the content is very abstract to a new biologist), so have added a long introduction on various types of reproduction. It’s long, however, so it may be overboard (especially if you’re not too excited about it).

License information

• This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.

• The slides in this presentation were originally created by Marc C. Perkins (http://faculty.orangecoastcollege.edu/mperkins).

• You are free to use, modify, and distribute these slides according to the terms of the Creative Commons license (e.g., you must attribute the slides, no commercial uses are allowed, and future distributions must be licensed under a similar license).

• Attribution should be given to Marc C. Perkins (and any later editors), including a link back to Marc’s current website. This applies both while distributing the slides and during use of the slides; attribution during use can be satisfied by, for instance, placing small text on at least one of the slides that has been shown (see below for an example).

Slides in this presentation based on those created by Marc C. Perkins. http://faculty.orangecoastcollege.edu/mperkins

History

• August 2007: Marc Perkins released first version. http://faculty.orangecoastcollege.edu/mperkins

(If you modify these slides and redistribute them, add your information to the list)

Extra images

Amanita muscaria

CC Image from: http://flickr.com/photos/algreer/265844261/in/set-399116/

Paramecium

CC image from: http://flickr.com/photos/nebarnix/309954509/