Unit 4 Lab Project: List of Species

one
Scientific name: Prunus avium
Common name: Bing cherry
Interaction: Symbiotic. Provide food to humans. Humans provide CO2, farmers nurture and multiply the species.
Domesticated: Yes. Farmers raise cherry trees.
Future: Symbiotic relationship will hopefully continue! I love cherries.

two
Scientific name: Canis familiaris
Common name: Beagle
Interaction: Symbiotic. Humans breed and care for beagles...house them, feed them. Beagles are watchdogs (in terms of altering owners to potential invaders) and great companions.
Domesticated: Yes.
Future: Symbiotic relationship will continue.

three
Scientific name: Acer griseum
Common name: Paperbark maple
Interaction: Symbiotic. Humans provide CO2, plant and nurture. Provide oxygen, shade, beauty, enjoyment to humans.
Domesticated: Yes. Farmers raise these trees to sell for others to plant and nurture.
Future: Symbiotic relationship will continue.

four
Scientific name: Zinnia sp.
Common name: Zinnia
Interaction: Symbiotic. Humans plant and care for. Zinnias provide beauty, enjoyment.
Domesticated: Yes. Farmers raise zinnias to sell.
Future: Symbiotic relationship will continue.



five
Scientific name: Taxodium distichum
Common name: Bald cypress
Interaction: Symbiotic. Humans provide CO2 and care for trees. Bald cypress provides oxygen, shade, beauty, enjoyment
Domesticated: Yes.
Future: Symbiotic relationship will continue.

six
Scientific name: Clupea harengus
Common name: Sardines.
Interaction: Predation. I have tried to think of a way that humans are of some benefit to herring, but I have not been able to come up with any!
Domesticated: No.
Future: Predation will continue. Humans will continue to hunt and eat herring.

seven
Scientific name: Scolopendra heros
Common name: Giant desert centipede
Interaction: Commensal/symbiotic. They benefit humans by eating cockroaches. The thought is revolting to me, but some people may keep them as pets!!!
Domesticated: No.
Future: I think the relationshiop will remain mostly commensal.

eight
Scientific name: Sylvilagus floridanus
Common name: Eastern cottontail
Interaction: Symbiotic. Unfortunately, humans provide tasty vegetation for rabbits. Some humans eat rabbits.
Domesticated: Yes, some species.
Future: Symbiotic relationship will continue.

nine
Scientific name: Casmerodius albus
Common name: Great egret
Interaction: Symbiotic...maybe mutualistic. Humans provide retention ponds as a habitat for the egret. The bird provides beauty and enjoyment.
Domesticated: No.
Future: Symbiotic/mutualistic relationship will continue.

ten
Scientific name: Acer palmatum atropurpureum
Common name: Red Japanese Maple
Interaction: Symbiotic. Provide oxygen, beauty, enjoyment to humans. Humans provide CO2, plant and care for.
Domesticated: Yes. Humans must nurture them.
Future: Symbiotic relationship will continue.

eleven
Scientific name: Fagus sylvatica 'Tricolor'
Common name: Tricolor European Beech
Interaction: Symbiotic. Provides oxygen, beauty, enjoyment to humans. Humans multiply and care for.
Domesticated: Yes. See above.
Future: Symbiotic relationship will continue.



twelve
Scientific name: Lycopersicon esculentum L
Common name: Tomato
Interaction: Symbiotic. Tomatoes provide food, humans raise and care for the plants.
Domesticated: Yes. Farmers raise them.
Future: Symbiotic relationship will continue.

thirteen
Scientific name: Zea mays
Common name: Sweet corn
Interaction: Symbiotic. Sweet corn provides food for humans. Humans plant corn like crazy.
Domesticated: Yes. Farmers raise corn.
Future: Symbiotic relationship will continue.

fourteen
Scientific name: Malus domestica Borkh
Common name: Braeburn apple
Interaction: Symbiotic. Apple tree provides food to humans. Humans plant and nurture the trees.
Domesticated: Yes. Farmers raise apple trees.
Future: Symbiotic relationship will continue.

fifteen
Scientific name: Vaccinium corymbosum
Common name: Blueberry
Interaction: Symbiotic. Bush provides delicious fruit to humans. Humans plant and care for the plant.
Domesticated: Yes. Farmers raise blueberry bushes.
Future: Symbiotic relationship will continue.

sixteen
Scientific name: Asparagus officinalis
Common name: Garden asparagus
Interaction: Symbiotic. Asparagus is food for humans and humans plant it.
Domesticated: Yes.
Future: Symbiotic relationship will continue.

seventeen
Scientific name: Fragaria ananassa
Common name: Strawberry
Interaction: Symbiotic. Strawberry is a tasty food for humans. Humans plant the strawberry bush.
Domesticated: Yes.
Future: Symbiotic relationship will continue.

eighteen
Scientific name: Lactuca sativa
Common name: Leaf lettuce
Interaction: Symbiotic. Lettuce is a food source for humans. Humans plant many seeds a year to grow lettuce.
Domesticated: Yes. Farmers raise lettuce.
Future: Symbiotic relationship will continue.

nineteen
Scientific name: Arachis hypogaea L.
Common name: Peanut
Interaction: Symbiotic.
Domesticated: Yes. Farmers raise peanut plants.
Future: Symbiotic relationship will continue.

twenty
Scientific name: Achillea millefolium
Common name: Yarrow
Interaction: Symbiotic. Yarrow provide beauty and oxygen to humans. Humans plant and nurture yarrow.
Domesticated: Yes. Farmers raise yarrow to sell to others.
Future: Symbiotic relationship will continue.

Unit 4, Online Lab #2: Demographics

SIMULATION SCREEN SHOTS

World and low fertility rate (Greece):














World and high fertility rate (Zaire):














QUESTIONS AND ANSWERS

1. What was your high fertility rate country and what was its fertility rate?
-> The high fertility rate country that I chose was Zaire. Its fertility rate was 6.10.

2. What was your low fertility rate country and what was its fertility rate?
-> The low fertility rate country that I chose was Greece. Its fertility rate was 1.50.

3. The initial demographic "shape" of your high fertility rate country should have been a pyramid, with high population in young age groups. Explain why high fertility rate results in a high percentage of young people in the population. How does this affect future population growth?
-> A high fertility rate means that on average couples are having more than 2 kids. By having more than 2 kids, each couple is increasing the size of the next generation. This means there will be a higher percentage of young people compared to the previous generation. As those kids reach reproductive age, there will be more people at that stage compared to the amount there were at that stage in the previous generation. If the fertility rate is still high, that generation will produce more individuals than they have in there own. In this way, a high fertility rate has an impact on future growth.

4. Your low fertility rate country might have had a more oval-shaped curve with high population in middle age groups. This is especially exaggerated if the fertility rate is below 2.00. Explain why low fertility rate leads to lots of middle-aged people.
-> If the reproductive age group has less on average than 2 kids per couple, they are going to leave the next generation with few people than they have. If this trend continues, the middle aged group will always be larger than the younger generations.

5. Write ten adjectives or descriptive phrases for what you might expect life, people's attitudes, conditions on the streets, etc. will be like in each of those situations. Imagine a situation with lots of middle-aged and older people in the population and write ten quick "brain-storm" descriptors for you think it would be like (Prescott, Arizona?). Then do the same for a situation with lots of children in the population.

Lots of middle age/older: working, traveling, comfortable, expendable income, free time, health care, health check ups, nursing homes, hip replacements, obituaries

Lots of children: daycare, poor, one income families, schools, errands, sharing ideas, screaming, playing, giving, hungry

Unit 4, Online Lab #1: Embryonic & Fetal Development

LIST OF TEN SIGNIFICANT EVENTS DURING EMBRYONIC AND FETAL DEVELOPMENT
--quick description of what the event is
--when (hour, week, day or month) during development when it occurs
--why you think it is significant
--image or photo of that event or stage for five of the events


Fertilization
description: Union of egg and sperm in the oviduct
timing: 0 to 24 hours post-ovulation
significance: A required step. Many steps leading up to fertilization must occur for it to be successful. Many things can go wrong preventing its occurrence.
















Cleavage
description: Duplication division.
timing: 1.5 to 3 days post-ovulation
significance: It is the first instance of mitotic cell division. All daughter cells receive the full 46 chromosomes.











Blastocyst
description: The morula moves down from the oviduct into the uterus. Cells flatten and form a hallow cavity. The flattened cells form an inner cell mass. The structure is now called a blastocyst.
timing: 4 days post-ovulation
significance: The cells that make up the inner cell mass will later become the embryonic disk. The outer cells walls will become the chorion. The chorion will contribute to the formation of the placenta.











Implantation
description: The blastocyst continues down into the uterus and secretes enzymes that allow it to implant in the uterine wall.
timing: 5 to 8 days post-ovulation
significance: A required step. Without implantation, the pregnancy will not continue.














Embryonic disk
description: Formation of embryonic disk
timing: 8 to 12 days post-ovulation
significance: Marks the start of gastrulation. The embryonic disk will later form the primary germ layers.

Primary germ layers
description: The embryonic disk forms tissue layers called the primary germ layers.
timing: 13 days post-ovulation
significance: All of the organs and tissues in an adult human can be traced back to the 3 primary germ layers, ectoderm, mesoderm, and endoderm.


Nervous system / heart
description: The nervous system becomes visually evident. Development of the heart begins.
timing: 21 to 23 days post-ovulation
significance: The nervous system will continue to develop leading to reflexes that are required for survival later in life. The heart will continue to develop allowing oxygen rich blood to reach tissues and organs

Bones
description: Cartilage starts to be replaced by bones.
timing: 3rd month
significance: The skeleton contributes to so many important functions: movement, support, protection, production of red blood cells, storage of minerals and fat.

Movement
description: The mother begins to feel movement.
timing: 5th to 7th month
significance: Although the fetus will begin moving sooner (which is equally important), this is an important moment for the mother. A potentially life changing experience.


















Lungs
description: The lungs are capable of breathing air.
timing: 23 to 26 weeks post-ovulation
significance: The surfactant secreted by the lungs prevents them from sticking together. If born premature, the lungs of a child born at this stage can perform gas exchange.

Unit 3 Lab Project: Build a Movable Limb

INTRODUCTION:

The purpose of this lab was to
1. Create a movable limb
2. To demonstrate how muscle action is initiated
3. To demonstrate the process by which the muscle actually contracts

These 3 items were to be built using regular household items. I ended up using 4 models to demonstrate all of the details that were required.

MODEL:
Limb parts listed with materials that represent each.

Movable Limb
Biceps brachii - artificial evergreen branch
Humerus - cinnamon stick
Radius - cinnamon stick
Ulna - cinnamon stick
Capitulum - small, sparkly gold ball covered with masking tape
Trochlea - small gold bell covered with masking tape

Materials:









Building the limb:









A movable limb - as the biceps brachii contracts, the radius (along with the ulna) moves toward the humerus:










Muscle fiber with axon
Sarcolemma - purple plastic wrap
T tubule - thin green paper-coated wire
Myofibrils - glue sticks
Axons - brown pipe cleaners
Schwann cells - oval wooden beads

Materials:









Building the muscle fiber and axon:









The muscle fiber with axons:








Note: After uploading this image, I realized I made a mistake on this one. I should have had one axon with several axon terminals reaching to the 2 muscle fibers.

Lastly, a basic image of one myofibril showing how the individual sarcomeres line up along the length of it:









Sarcomere
Myosin - artificial evergreen limb with masking tape around the center
Myosin head - artificial evergreen needle
Actin - natural jute rope
Troponin - cloth rose
Tropomyosin - gold bead rope
Sarcoplasmic reticulum - green jute rope
Calcium ions - red hearts

Materials:









Building the sarcomere:









The sarcomere:









The sarcoplasmic reticulum in close vicinity to the sarcomere. In the photo on the left, calcium is stored in the sarcoplasmic reticulum. The photo on the right shows the release of the calcium ions from the sarcoplasmic reticulum:









Calcium ions combine with troponin on actin:









Myosin heads attach to actin in the photo on the left. In the photo on the right, the power stroke of the myosin heads moves the actin filaments past the myosin filaments. In this way, the actin filaments approach one another and the sarcomere shortens. As the sarcomeres of a myofibril shorten, the myofibril shortens. This is how a muscle contracts:









Action potential
Axonal membrane - wooden blocks
Sodium ions - white textured balls
Potassium ions - wooden balls
Gated sodium ion channel - green lettered wooden blocks
Gated potassium ion channel - red lettered wooden blocks

Materials:









Resting potential:









Action potential begins as gated sodium ion channels open, sodium ions move from outside of the axon to the inside. The action potential propagates along the axon as the sodium channels open from left to right, sodium move inside the cell, and the inside of the cell changes from -65mV to +40mV. This voltage change also moves from left to right, which is the propagation of the action potential:










Action potential ends as the voltage changes back from +40mV to -65mV. This change happens as the gated potassium ion channels open to allow potassium ions to move from the inside to the outside of the axon. This voltage change also occurs from left to right along the axon:











CONCLUSION
The four models provide above detail several important functions of our body. First, the movable limb model shows how the contraction of a muscle can move a limb around a joint. Second, the model of the muscle fiber shows the basic structures that are involved with muscle contraction. It also lays the groundwork to understand how sliding of the filaments of the sarcomere result in contraction of the muscle fiber. The third model details the structures of the sarcomere and shows how calcium ions are released from the sarcoplasmic reticulum and then combine with troponin on the actin filaments. It also shows how the myosin power stroke slides the actin filaments towards each other to shorten the sarcomere. And the last model illustrates the movement of sodium and potassium ions across the axonal membrane. The movement of these ions contributes to the action potential.

Unit 3, Online Lab #2: Muscle Function

INTRODUCTION:
Sitting upright. Walking. Running. Bending. Stretching. Staying warm. Distributing oxygen. From the simple to the complex, each of these activities requires muscle action. At the core of muscle action are two protein filaments, actin and myosin. Initiation starts in the nervous system and the signal to contract is trasmitted from a motor neuron to a muscle fiber by a neurotransmitter, acetylcholine (ACh). Once ACh diffuses accross the synaptic cleft and binds to receptors in the sarcolemma, an impulse is generated that spreads down into the T tubues to the sarcoplasmic reticulum (SR). This releases calcium ions from the SR, and contraction of the sarcomere is initiated.

The purpose of this lab is to understand how and why temperature and fatigue effect muscle action.

MATERIALS AND METHODS:
Here are pictures of how I performed each part of the lab.

To test the effect of temperature on muscle action, I submerged my hand in ice cold water for one minute (which hurt very bad, I must add!!).
To test the effect of fatigue on muscle action, I squeezed the green ball.
DATA:

ANALYSIS OF DATA:

1. What are the three changes you observed in a muscle while it is working (contracted)?
The relaxed muscle felt soft, the contracted muscle felt hard.
The relaxed muscle was shorter than the contracted muscle.
The circumference of the contracted muscle was larger than that of the relaxed muslce.

2. What effect did the cold temperature have on the action of your hand muscles? Explain.
After submersing my hand in cold water for one minute, I could hardly make a fist. The muscles felt slow and sluggish; it actually hurt a little. It was like the movement of my hand was not working as fast as my brain wanted it to.

3. What effect did fatigue have on the action of your hand muscles? Explain.
By the end of the first set, the speed at which I could contract started to slow down. The squeeze itself also felt alot weaker. The action slowed because my hand started to ache and cramp.

PROBLEMS WITH DATA OR TECHNIQUE:
You will notice in my data for the fatigue trials, that the number of repetitions in the fourth trial was the same as the third trial and that the number of repetitions increased in the 5 trial. This can be explained by the fact that after the fifth trial I realized that my squeezes had gotten very weak. In the sixth trial I concentrated on trying to apply the same force as the squeezes that I performed in the first trial, and noticed that it did take longer compared to when I was not concentrating as much (in the 4th and 5th trials).

I was also using as online counter to time the 20 seconds and I had to reset after each trial. This allowed some time for rest in between each trial.

CONCLUSION:
This lab showed that both temperature and fatigue impact muscle performance. After my hand was submerged in ice cold water, the movement of hand was very slow and sluggish. Similarly, after each set (and after each repetition) the movement of my hand also slowed.

In both instances, the muscles are being asked to work at sub-optimal levels. In cold temperatures, blood vessels and capillaries restrict, reducing the amount of blood flow to the area. With less oxygen being delivered to the area, production of ATP will be slowed. Without plentiful ATP, it will take longer for all of the myosin heads to return to the resting position, increasing the amount of time between power strokes. Diffusion of the ACh across the synaptic cleft probably takes longer and relase of the calcium ions takes more time as well.

The cause of the slowed action while squeezing the ball is most likely due to the buildup of lactic acid. It is toxic to cells and caused the cramping and aching that I felt. The cramping when away once I stopped squeezing and enough oxygen was delivered to the area to allow breakdown of the lactate to pyruvate.

For a visual representation of how a sarcomere contracts, I went to our book. I really like Figure 12.5. It shows the structure of a muscle fiber, and it also shows the sarcomere, in the relaxed position and in the contracted position.










The source of this image is the text for our class:
Mader, Syliva S. Human Biology. New York, NY: McGraw-Hill (2008).
The digital image was downloaded from the power point presentation for Chapter 12 on the Aris website.

This image illustration shows the specific action of actin and myosin. This image was taken from the Owensboro Community & Technical College's Anatomy and Physiology I notes page.

Information in the introduction and conclusion was taken from our textbook:
Mader, Syliva S. Human Biology. New York, NY: McGraw-Hill (2008).