Exam 3 Biology

All things about bacteria & Archaea

Horizontal Gene Transfer

Movement of DNA from different species, a major source of genetic diversity

Conjugation

DNA directly transferred between bacteria through cell-to-cell contact.

Transformation

DNA is taken from the environment by a bacterium and transferred it to its genome

Transduction

DNA transferred between bacteria by a virus.

Extremeophiles

Can live in high salt, high temp, high pressure, high acidity, or low temp environments

The Germ Theory

1. The microbe must be present in the affected person but not in the unaffected

2. The microbe must be isolated and grown in pure culture

3. If the microbe is injected into a healthy individual, the disease will result

4. Must be able to culture the microbe from a newly infected individual

Photoautotroph

Organisms that use light energy to convert carbon dioxide and water into organic compounds.

Chemoautotroph

Organisms that obtain energy by oxidizing inorganic substances and use carbon dioxide as their carbon source.

Photoheterotroph

Organisms that use light energy and organic compounds for growth rely on other organisms for carbon.

Chemoheterotroph

Organisms that obtain both energy and carbon by consuming organic compounds, relying on other organisms for nutrients.

Eukaryotic Cells

Cells characterized by a nucleus organelles, and cytoskeleton. including plants, animals, fungi, and protists.

Endocytosis

The process by which cells engulf material from the external environment, bringing it into the cell.

Endosymbiosis Theory

The theory that eukaryotic cells originated through a symbiotic relationship between different species, where one cell engulfed another.

Protozoans

single-celled eukaryotic organisms that can move and are often found in aquatic environments. they ingest their food

Slime molds

Major decomposers

Diatoms

a single-celled alga that has a cell wall of silica.

Primary Endosymbiosis

the initial event where a eukaryotic cell engulfs and retains a prokaryotic cell, resulting in the formation of organelles like mitochondria and chloroplasts

Secondary Endosymbiosis

occurs when a eukaryotic cell engulfs another eukaryotic cell that already contains a primary endosymbiont, such as a chloroplast, resulting in the host cell acquiring organelles from two lineages

Synapomorphies of Fungi

1. Cell walls contain chitin

2. single smooth flagellum

3. store sugar as glycogen

Saprophytes

Decompose dead matter and breaks down lignin and cellulose

Fruiting bodies

Reproductive structure made of hyphae

Plasmogamy

Fusion of Cytoplasm

Karyogamy

Fusion of nuclei

Ecological Roles of Plants

1. Base of the food chain

2. Produce oxygen

3. habitat

4. hold water

5. moderate local climate

Distinguishing feature of land plants

1. Multicellular

2. Have chlorophyll a and b

3. store food as amylose starch

4. Cellulose cell walls

5. diploid and haploid generations

Advantages of life plants

Access to more light and CO2

Challenges to land plants

In a dry environment, resources are separated and gravity pulls them down.

Land Plant adaptations

1. Waxy cuticle

2. Stomata

3. Reproductive spores

4. Vascular System

5. Ligin

Gametophyte

Haploid and make gametes

Sporophyte

Diploid and makes spores

Moss Life cycle

1. Gametophyte is dominant

2. gametophyte is the first stage while sporophyte is the second stage

Nonvascular Plants

They have no vascular tissue to conduct water and no support. They usually live very close to the ground and have a gametophyte-dominant life cycle.

Angiosperms

Species of flowering plants that is sporophyte-dominant.

Vascular plants without seeds

1. has a sporophyte dominant life cycle

2. includes lycophytes, ferns, & horsetails.

The origin vascular tissue

1. Simple water-conducting cells

2. First vascular tissues

3. tracheids

4. vessel elements

tracheids

long, thin cells with 2 cell walls and a pit where water can flow. an

Antheridum

Sperm producing gametangia

Archegonium

Egg producing gametangia

Gametangia

Gametes produced in

Synapomorphies of Fungi

-Cell walls contain chitin

-Single smooth Flagellum

-Store sugar as glycogen

Mycorrhizae

a symbiotic relationship between plant roots and fungi that helps plants absorb nutrients and water

saprophytes

-decompose dead matter

-Break down ligin+cellulose

Hyphae

long, thread-like filaments or tubes that form the body of fungi, collectively known as mycelium

Fruiting Bodies

-reproductive structures made of hyphae

Chytids

Fungi group that has Flagellated spores, live in wet environment, aquatic

Zygomycota

Zygote has a tough outer layer

-asexual

-decomposers

Basidiomycota (mushrooms)

-Made pedestal-like basidium

-club fungi

-diverse

Ascomycota

Makes a sac-like ascus

-commonly reproduce asexually

-live in almost every terrestrial habitat

Lichens

-mutualism between fungi and green algae

Adaptations of Fungi

-Extracellular digestion

-Degrades lignin matrix

-has multiple sexes

mutualistic relationship

Both species benefit

Parasitic

One benefits while the other suffers

Commensal

One benefits while the other remains unharmed

EMF

Forms sheaths around roots & penetrate root cells

AMF

contacts the plasma membrane around the root cell.

Hypotonic Cells

Turgid, H20 moves into the cell

Hypertonic

Plasmolyzed cell, H20 moves out of cell

Isotonic

Flaccid, H20 moves in/out of cell

Land plant adaptations

-waxy cuticle, thick epidermis, stomatal cyst

Solute potential

Always negative or 0 relative to pure water

based on solute concentration

Pressure potential

Pushing creates positive while pulling creates negative

Function of stomata

Opens when light outside, there is low CO2 in the cell, and they have an internal clock. They close when they have water and with high temps.

Water potential in stomata

open- high water potential

closed- Low water potential