Biology (UC Davis BIS2B) Lab Practical Flashcards

Biodiversity

A term to describe the diversity that encompasses all the organisms (animals, plants, fungi, bacteria, algae) on the earth.

Random Sampling

Sampling done randomly to avoid any bias in the observation and sampling results.

Representative Sample

A sample taken that accurately represents the designated area or habitat.

Sampling Schemes

Methods or techniques used to sample habitats and their biodiversity.

Transect Sampling

A sampling scheme in which a biologist runs a line, called a transect, through the habitat. Every organism found within a fixed distance from the line is recorded.

Quadrat Sampling

A sampling scheme in which the habitat is divided into rectangles of known size, called quadrats. A certain number of quadrats are randomly selected for sampling.

Relative Abundance

A way of looking at diversity that involves looking at how many of each species are present.

Shannon-Wiener Index

A diversity index or value that measures species richness as well as relative abundance (or evenness)

Also known as H'.

Rarefaction Plots

A graph or plot that compares the number of individuals with the number of species found in a sampling of a habitat.

Often used to show or decide when one should stop sampling (when the number of new species found reaches 0; when the slope reaches 1).

Autotrophs

Organisms that make their own food.

Heterotrophs

Organisms that must feed on other organisms to receive their needed energy, and cannot make their own food.

Photosynthesis

A process in which light is captured and used to make ATP, the currency for biological energy.

Glucose is a final product of photosynthesis.

Requires sunlight and carbon dioxide to form carbohydrates (starch and sugar).

Chemoautotrophy

A process that uses carbon dioxide as a carbon source (like photosynthesis), but derives energy from breaking apart the chemical bonds in substances (oxidizing the substances) such as H2S, NH3, or CH4, instead of absorbing it from light energy.

Extracellular Digestion

A digestion process that takes place in the gut and outside of the cells.

Intracellular Digestion

Part of the digestion process that takes place when the products are absorbed into the cells for further breakdown of the food.

Cellular Respiration

A process that is almost like a follow up to photosynthesis.

Glucose is broken down in glycolysis in order to create energy and ATP.

Decomposers/Saprobes

Organisms that absorb nutrients from dead organisms or biological waste products.

Parasites

Organisms that collect nutrients from living hosts without killing the hosts.

Biotrophs

Fungi that utilize nutrients from living cells not killing them.

Pathogens

Fungi that also cause diseases, often in the host.

Surface Area to Volume Ratio

A higher surface area to volume ratio allows for easier transport of molecules through the membranes.

A lower surface area to volume ratio makes it easier for the organ to lose moisture.

Photoautotrophs

Organisms that convert the energy in sunlight to chemical energy via photosynthesis.

Light-Harvesting Pigments

Pigments that absorb different wavelengths, and as a result, reflect a specific light/color.

Chlorophyll a

The most common pigment (one of three forms: a, b, c) and absorbs light of 430nm and 670nm (violet and red light), reflecting green light (most plants have chlorophyll).

Thin Layer Chromatography (TLC)

A technique used to separate pigments using plates. Can be used to separate pigments of algae, flowering plants, etc.

Algae Ball Experiment

In the experiment, it is observed that when undergoing photosynthesis (exposed to light), the level of CO2 drops in the vials with algae balls, lowering the acidity of the solution, and raising the pH.

Dark vial: Respiration without photosynthesis (CO2 increased, lower pH)

No algae: Neither respiration/photosynthesis are happening

Advantage of Multicellularity

Multicellularity allows parts of the body to be specialized for functions such as photosynthesis or nutrient absorption.

Methods of Increasing Body Size for Multicellularity

1) Colonial body plan- when cells divide by mitosis to produce new cells, but they remain attached to each other.

2) Filamentous body- involves repeated divisions along the same plane (divide and grow in a single line/plane)

3) True three-dimensional- where cells can divide in any plane; complex organisms form from this kind of body plan

Totipotent

Dividing cells that remain undifferentiated, and whose fates have not been decided- they have potential to specialize in almost anything.

Meristems

Groups of totipotent plant cells that are not evenly distributed throughout plant tissues

Tissue

A group of cells specialized for a particular function.

Organ

A collection of tissues that work together.

Shoots

Includes the leaves and stems on a plant:

Leaves

Typically flat and broad; specialized for photosynthesis with a waxy cuticle that protects the photosynthetic cells from drying out.

Stems

Typically long and narrow; specialized to transport water and nutrients between the leaves and roots.

Nodes

Parts of a stem where leaves are attached and lateral shoots may emerge.

Internodes

Regions between nodes.

Roots

Typically long and branched; specialized to take up water and nutrients and to transport those materials to the rest of the plant using the central vascular tissue. NO nodes or internodes.

Vascular Tissue

Tissue used to transport nutrients and water (in animals and humans, blood vessels are a vascular tissue).

Found in roots, stems, and leaves.

Lateral Roots

Roots that grow laterally instead of just vertically, and actually increase root surface area.

Root Hair

Can help further increase root surface area, and are formed when a single epidermal cell extends outward in a tube.

Xylem

A kind of vascular tissue that moves water and dissolved nutrients up from the roots into the shoot.

Phloem

A kind of vascular tissue that circulates sugars and amino acids throughout the plant body.

Apical Meristem

The apex of the central stem, and contains undifferentiated actively dividing cells, which will either eventually become cells with fixed fates or become more undifferentiated meristem cells.

Lignin

Strong, light-weight carbon polymer that acts as a modified vascular tissue (xylem) and make up a really firm support.

Endodermis

A ring of cells that surrounds the vascular tissue.

Casparian Strip

A waxy layer made up by the endodermis, which prevents water passage.

Macronutrients

Elements needed in relatively high amounts- include carbon, nitrogen, and phosphorous.

Micronutrients

Elements needed in relatively tiny amounts- includes boron and molybdenum.

Mobile Element

An element that can be readily moved through plant vascular tissues. Plants usually show deficiency for these elements in older leaves first.

Immobile Element

An element that is not as readily moved through plant vascular tissues. Plants usually show symptoms in younger tissues.

Fine Roots

Very thin hairs that give roots a lot of surface area to mint he soil around them.

Course Roots

Roots with few hairs and minimal surface area for uptake and cannot search for nutrients as effectively.

Mycorrhizae

Fungi that create a mutualistic relationship with plants.Plants with them are able to absorb more nitrogen and phosphorous, while carbon compounds collected via photosynthesis is made accessible to the fungi.

Nodules

Round balls that form when bacteria invades the root tissues, forming a mutualistic relationship between bacteria and plants in the pea family.

Flowers

The sexual organs of plants, where gametophytes are housed.

Endosperm

A triploid tissue formed from a triploid nucleus dividing many times.

A nutritive tissue that supports early growth of the diploid plant embryo.

Seeds

Where the endosperm stores nutrients on a plant.

Fruits

Where nutrients are stored at the base of the flower, inside an ovary (that enlarges after fertilization).

Adaptation

To evolve specializations to match extreme conditions (long term).

A trait that increases fitness.

Acclimation

To have the ability to alter one's phenotype (short term).

Tropisms

Movement in response to a stimulus.

Gravitropism

Movement in response to gravity.

Phototropism

Movement in response to light.

Phenotypic Plasticity

The genetic ability to acclimate by producing different phenotypes in different conditions.

Blind Guts/Two-Way Guts

Saclike guts that have one opening, and anything that cannot be digested is released via the mouth.

Complete Guts/One-Way Guts

Continuous tubelike guts that have two openings, consisting of a mouth and an anus. Food moves in one direction from entrance to exit.

Processing Guts

Guts that contain regions of the digestive tract specialized for particular functions.

Essential Nutrients

Nutrients that cannot be synthesized and must be obtained from the diet.

Herbivores

Heterotrophs that eat plants.

Carnivores

Heterotrophs that eat animals.

Omnivores

Heterotrophs that eat plants and animals.

Detritivores

Heterotrophs that eat decaying plant or animal matter.

Scavengers

Heterotrophs that eat refuse or prey items abandoned by predators (carnivores).

Predators

Organisms that catch and kill live prey.

Suspension Feeders

Organisms that collect food particles suspended in water (plants or animals) and use a filter system to access their food.

Deposit Feeders

Organisms that pick up food that has fallen onto a surface (been deposited). Food can either be plants, animals, or detritus (decaying plant or animal matter).

Phagocytosis

A method used by single-celled organisms in which they take food into their bodies by engulfing it, or having a permanent cell opening that functions like a mouth.

Anthocyanin

A pigment that is present in the yellow-green leaf morph of the Brassica Rapa, giving the leaves a purple coloration.

Trichomes

Small hairs on the stems and leaves of the yellow-green moreph of the Brassica Rapa.

Homodont Dentition

Rows of identical teeth; animals with these usually swallow their prey whole.

Heterodont Dentition

A variety of specialized teeth used for shearing, crushing, or grinding.

Canines

Teeth used to grasp and hold onto prey.

Incisors

Teeth toward the front of the mouth, used to clip off plant material.

Molars

Teeth located towards the back, are relatively uniform with broad surfaces and often folded, and are used for grinding food.

Diastema

A region where canines and premolars would be in other animals, but in herbivores, is a gap in the jaw where there is no teeth.

Hyphae

Elongated branching strands that make up the mycelium of fungi and plants; they grow outward as they digest their food source.

Oxygen Pickup

The part of the respiratory system where the gills or lungs play a part in picking up oxygen from the air or water.

Oxygen Distribution

Usually conducted by the blood in the circulatory system, it distributes the oxygen throughout the organism's body for use.

Function for Total Population

N(t-1) + B - D = N(t)

Population Density

Number of individuals present in a certain area.

(# of organisms/available area).

Space Allotted To Each Organism

(available area/# of organisms)

Intraspecific Competition

When organisms compete with members of their own species for resources.

Density-Dependent

When the rates (birth, death, or net rates of change in population size) are affected by the density of organisms already present at each time period.

Finite Rate of Increase (lamda)

N(t+x)/N(t)

-Finite rate of increase, or the per-individual growth rate across any two time periods.

Per-Day Finite Rate of Increase

[N(t+x)/N(t)]^(1/x)

Testable Hypothesis

A hypothesis made that can be tested repeatedly.

Fission

A process in which population increases and grows when each organism divides, forming individuals that are genetically identical to the old.

Working Hypothesis

One's hypothesis that can be tested- similar to a testable hypothesis- and is the main goal of an experiment.

Null Hypothesis

A statement of what you would see if your hypothesis is NOT correct.

A statement of no difference between the variables you are going to measure, or a statement of no change, or no effect.