Living Environment STuding Part 3 Flashcards
(8 cards)
Reproductive Technology:
- Artificial insemination: using sperm from a donor
- Amniocentesis: removing some of the cells from the amniotic fluid which protects the fetus and analyzing their DNA.
- Karyotype: is a visual map of chromosomes. Can be used to see if the fetus has any chromosomal problems like Down’s syndrome (3 copies of chromosome #21)
why is biodiversity loss bad
Biodiversity refers to the variety of life on earth. As habitats are lost and species become extinct, biodiversity is reduced. This is considered to be bad because:
1. Ecosystems with low diversity are less stable than ecosystems with more diversity,
2. Ecosystems with low diversity take longer to recover from environmental changes
acid rain
Caused by things like burning fossil fuels
Acid rain that seeps into the ground can dissolve nutrients, such as magnesium and calcium, that trees need to be healthy
Sulfur and nitrogen compounds in air pollution dissolve in the moisture of the atmosphere to form acids, causing rain to have a low pH (acidic).
Acid rain kills trees and destroys historical artifacts.
A. Making Connections (aka The Clothespin Lab)
- Part A1
a. Whatyoudid:measuredhowexerciseaffectedpulserate. b. What you learned: exercise increases pulse rate - Part A2
a. What you did: Squeezed a clothespin for 1 minute, then squeezed it again for another minute
b. What you learned:
1) If you squeezed more the second round, it may have been because your finger muscles were “warmed up” from increased circulation.
2) If you squeezed less the second round, it may have been because your finger muscles were fatigued.
B. Relationships and Biodiversity (Botana curus lab)
- What you did: Compared 4 species of plants, based on structural (physical) and molecular (chemical and genetic) traits.
- What you learned:
Species that are related share similar traits.
Different techniques (such as gel electrophoresis and paper chromatography) can be used to determine relationships between organisms.
c. Endangered species should be protected because they may offer benefits to humans.
C. BeaksofFinches
What you did: Played different finch species competing for food.
What you learned: Different environmental conditions (food) favored different species of finch, allowing some to survive and reproduce, but not others.
D. Diffusion Through A Membrane 1. Part A
What you did:
Madeamodelcellusingdialysistubing.
Put glucose and starch inside your “cell.”
Put starch indicator (iodine) outside cell.
What you saw:
Inside of cell turned black because iodine diffused into the cell.
Because outside of the cell was not black, you know the starch did not diffuse through the membrane.
Used blue glucose indicator (Benedict’s solution) to see that glucose did diffuse through the membrane.
What you learned:
Small molecules (glucose, iodine) can diffuse through a membrane on their own.
Large molecules (starch) cannot diffuse through a membrane on their own.
You can use indicators to identify the presence of specific substances.
- Part B
What you did:
Looked at red onion cells under the microscope.
Added salt water to the onion cells.
Added distilled (pure) water to the onion cells.
What you saw:
Salt water caused the onion cells to shrivel.
Distilled water cause the cells to swell back to normal.
What you learned:
Saltwater causes water to diffuse out of a cell.
In pure water, water will diffuse into a cell.
Gel Electrophoresi
A technique used to show how species are related to one another. Restriction enzymes cut DNA into fragments, which are placed into a well in a gel plate. An electric current carries the DNA fragments through the gel, separating them according to size (smaller pieces of DNA are carried farther from the well than larger pieces). Related organisms will show similar banding patterns because their DNA
