Exam 1 Flashcards
Cell Theory
Every living thing is made of cells: cannot be proved/disproved because there isn’t access to every living thing
Mycology
Study of fungi: mushrooms and related forms
Bryology
Study of bryophytes: mosses and related forms
Levels of study (9)
- molecules
- organelles
- cells
- tissues
- organs
- individual organism
- population
- community
- ecosystem
Population
Same kind, same location
Community
Very diverse, many kinds, one location
Ecosystem
Made by community and environment, varies by choice
Ex. log, forrest, Earth
Chloroplasts are
Organelles
Tissues can be told apart because
The cells that make them up are similar
Leaves, stems, and roots are
Organs
Ecosystems change due to (6) things:
- temperature*
- moisture*
- topography (mountains, flat, etc)
- human/animal influence
- disturbance factors (floods, volcanoes)
- time
When was Earth formed?
4.6 billion years ago
When was the formation of life?
3.8 billion years ago
When was the first evidence of fossilization?
3.5 billion years ago
When did photosynthesis begin and the atmosphere begin to change? (range)
2.5-1.8 billion years ago
When were the first Eukaryotic cells formed?
1 billion years ago
When were the first multicellular organisms?
750 million years ago
When was the invasion of land by plants?
460 million years ago
When did the first flowering plants appear?
160 million years ago
When did agriculture develop?
12,000 years ago
What was most likely the first terrestrial organism?
Algae, no fossils
Most life was formed where?
Water
1 millimeter is = to how many micrometers?
1,000 micrometers
How thick is 1,000 micrometers?
About the thickness of a dime
How big is a cell?
1 micrometer
Who is credited with “discovering” cells and in what year?
Hooke, 1966 ish
Which microscope increases magnification as light passes through a series of transparent lenses made of glass?
Light microscope
What can a light microscope do?
Distinguish organelles
What are the two types of light microscopes and their magnification?
Compound, 1500x and Dissecting, 30x
Which microscope produces a beam of electrons when high-voltage electricity passes through a wire?
Electron Microscope
What are the two types of electron microscopes and their magnification?
Transmission Electron Microscope (TEM), 200,000x with thin material and Scanning Electron Microscope (SEM), 10,000x 3D
Prokaryotic vs Eukaryotic
Prokaryotic cells do not have a nucleus and are typically smaller
Eukaryotic cells have a nucleus (mostly) and membrane bound organelles
What does the cell wall do?
Surrounds protoplasts
What are protoplasts?
All living cell components bound by the plasma membrane
How much room does a vacuole take up?
Most of the interior and squeezes the organelles to the sides
What increased efficiency in cell communication
Small cells, more surface area touching
What material is the cell wall structures from, and what is another example of it?
Cellulose, cotton
What are two characteristics of cellulose?
Strong and fibrous
What other materials help structure the cell wall?
Hemicellulose, pectin, glycoproteins
What is considered the mortar that holds bricks together?
Middle Lamella
When is middle lamella produced?
When new cell walls are formed
Secondary walls are derived from what?
Primary walls and lignin
What is Lignin?
Secondary growth, makes plants larger and harder
Ex. Lettuce vs an Oak. Oak has much more lignin
How do cells communicate?
Fluids and dissolved liquids/substances can pass through primary walls in gaps
What are the gaps/tunnels through the cell wall which cells communicate called?
Plasmodesmata
Which component of the cell has a phospholipid bilayer embedded with proteins?
Plasma Membrane
What component is bound by two membranes and has structurally complex pores that occupy 1/3 of the surface area?
Nucleus
What does nucleoplasm look like?
Short fibers
What does the Endoplasmic Reticulum do?
Facilitates cellular communication and material channeling
What does the Endoplasmic Reticulum look like?
Enclosed space consisting of a network of flattening sacs and tubes forming channels throughout the cytoplasm
What happens in the Rough ER and what does it look like?
Protein synthesis, Ribosomes are distributed on the outer surface
Ex. backpacks on a table
What happens in the Smooth ER and what does it look like?
Lipid Secretion, devoid of Ribosomes
What are Ribosomes composed of?
Two subunits made of RNA and proteins
What is another name for Dictyosomes?
Gogli bodies
What do Dictyosomes look like?
A stack of pancakes
What is the most conspicuous plastid?
Chloroplasts
What do each chloroplast contain?
Stroma and Grana
What is Stoma?
Enzyme filled liquid
What is Grana?
Stack of thylakoids
What to thylakoids contain and where?
Chlorophyll in the membrane
What chemical rxn occurs in the granum?
Photosynthesis
What color are chloroplasts?
Green
What color are Chromoplasts?
Red/orange
Ex. Tomato/pepper
What color are Leucoplasts?
Clear
Ex. Potato
Mitochondria is the __________ of the cell
Powerhouse
What does the Mitochondria do?
Releases energy produced from cellular respiration
What are the folds of the inner membrane of the mitochondria called?
Cristae
What do the cristae do?
Increase surface area available to enzymes in the matrix fluid
What can take up to 90% of the cell volume?
Central Vacuole bound by the vacuolar membrane
What is the vacuolar membrane called?
Tonoplast
What substance helps maintain pressure in the cell and contains what?
Cell sap, water-soluble pigments
An intricate network of microtubules and microfilaments
Cytoskeleton
What does a microtubule do?
Controls the addition of cellulose to the cell wall
Ex. The scaffolding of a house
What do microfilaments do?
Play a major role in the contraction and movements of cells in multicellular animals
Ex. Most plants (oaks) do not have the ability to move
What is another name for Cytoplasmic streaming?
Cyclosis
What is Cyclosis?
Movement inside the cell
Cell division is a process also referred to as
The Cell Cycle
Interphase has how many parts and what are they?
Three: G1, S, G2
What does the G1 phase do?
Increases in size
What does the S phase do?
DNA replication
What does the G2 phase do?
The mitochondria divide and microtubules are produced
What is the other part of the cell cycle besides interphase?
Mitosis
How many parts are there in mitosis?
Four: Prophase, Metaphase, Anaphase, Telophase
What does mitosis produce?
Two daughter cells that are exact copies (except in rare cases)
Where does reproduction occur in plants?
Meristem
What happens in prophase?
- chromosomes condense
- nuclear envelope disappears
- spindle fibers develop
How many parts of a chromosome is a chromatid?
Two
What happens in metaphase?
- chromosomes line up at center
- spindle fibers attach
What happens in anaphase?
- sister chromatids separate and are pulled to opposite poles
- spindles shorten
What happens in telophase?
- opposite of prophase
- cell plate appears
What is a centromere?
Ex. Everyone is wearing a belt and has to put the buckle on the floor, the buckles are the centromere
How are plant tissues able to be identified?
By groups of cells that are the same structure and function (they look alike and are roughly the same size)
How many Meristematic tissues are there and what happens in the meristem?
Three: Apical, Lateral, Intercalary. Reproduction!
What is a meristem?
A permanent region of active cell division
Where is the Apical meristem located?
In the tips of roots and shoots (at the ends)
What does the apical meristem do?
It increases length to make the plant and its roots taller
Production of new cells by the apical meristem is what kind of growth?
Primary
Examples of primary meristems are
protoderm, ground meristem and procambium
Where is the protoderm?
On the outside, as a covering, like skin– epidermis
Where is the ground meristem?
In the middle acting as a fill-in– produces tissues composed of parenchyma
Where is the procambium?
In the middle because it is vascular– produces primary xylem and phloem cells
What does the Lateral meristem do?
Produces secondary growth
What are the two Lateral meristems
Vascular cambium and cork cambium
What does the vascular cambium do?
Produces secondary vascular tissue
What does the cork cambium do?
Produces new covering (bark)
What is the difference between simple and complex tissues?
Simple tissue deals with and has one type of cell, while complex has multiple cells/tissues
Name three simple tissues
Parenchyma, collenchyma, and sclerenchyma
What does parenchyma do/look like?
Reproductive and thin, like bubbles
What does collenchyma do/look like?
Reproductive and thick on the corners, stringy (celery)
What does sclerenchyma do/look like?
Thick tough walls, dead when mature and fully functioning, contains lignin
Name two types or parenchyma and define then
- Aerenchyma: lots of air spaces
- Chlorenchyma: contains chloroplasts
What does collenchyma do?
It contains a living cytoplast and may live for period of time providing flexible temporary support
Name two types of sclerenchyma and define them
- Sclereids: stone cells, any shape with lumen filled with lignin
- Fibers: elongated, contain lumen, act as support
Name three complex tissues
Xylem, phloem, epidermis
What does the xylem do?
Main conducting tissue for water and minerals absorbed by the root
Types of xylem
- vessels, long tubes open at each end, major evolutionary step
- Tracheids, tapered at ends with pits
- Rays, allow for lateral conduction
What do pits do in tracheids?
They allow water passage between cells
Which came first, the vessel or the tracheid?
The tracheid
What does the torus do in a pit?
It controls water/mineral flow in and out on the cell
What does the phloem do?
Conducts dissolved food materials produced by photosynthesis throughout the plant, sugar and food movement
What is a Sieve Tube member?
Large, cylindrical cells that only have a cytoplasm
What is a Sieve plate?
A porous region in the Sieve tube, looks like a shower drain
What are companion cells?
Narrowed, tapered, nucleus of companion cell directs that cell and the sieve tube member cell
What is the epidermis?
Outermost cell layer like skin, one cell thick
What does the epidermis secrete?
A fatty substance called cutin on outer walls to prevent water loss
Root epidermal cells produce what?
Root hairs
What borders the stomata in leaves
Guard cells
What are trichomes?
Plant hairs
What is the point of having trichomes?
To protect from insects
Secretory cells can function in one of two ways:
Individually or as a secretory tissue
What are some examples or secretory tissues/cells?
Nectar, citrus oil, mucilage or glandular (waste product), latex (milk weed)
What does the periderm make up?
The outer bark
What is the periderm made up of?
Cork cells, and suberin that has been secreted into the walls from the cytoplasm
What is a lenticel?
Cork cambium loosely arranged around pockets of parenchyma (holes in the bark so you can breathe)
What are aerial roots?
Above ground roots
Name two major types or roots
- Fibrous root system: monocotyledonous (monocot)
- —grasses, many root
- Taproot system: dicotyledonous (dicot)
- —carrot, one main root
Root development begins with what?
Seed germination
What is the radicle?
The lower portion of the embryo
What is the root cap, what type of cell is it made of, what does it look like, what are the functions?
Thimble-shaped mass or parenchyma cells covering each root tip and it protects from damage to the tissue and functions in gravity perception
Where is the region of cell division?
The apical meristem (center of the root tip) at the edge of the inverted cup-shaped zone
What happens at the region of elongation?
The cells become several times their original length
What is the region of maturation?
Cells differentiate into various cell types, root hairs form, absorb water and minerals, thin cuticle
What is the cortex?
Cells that store food
What does the cortex contain?
The endodermis where the cell walls impregnated with superin to form casparian strips
What do Caspian strips do?
They force water and dissolved substances coming and going through the plasma membrane of the endodermal cells
Where is the vascular cylinder
Inside the endodermis
Where is the pericycle and what does it originate?
Directly inside the inner boundary of the endodermis and it originates lateral roots
What is the difference between determinate and indeterminate?
Determinate growth stops at a certain size, whereas indeterminate growth continuously adds new tissues
What kind of roots are sweet potatoes?
Food storage roots
What kind of roots are the pumpkin family?
Water storage roots
What kind of roots are fruit trees (that have buds that develop into suckers)
Propagative roots
What is a pneumatophore?
Spongy roots that extend above the waters surface (enhance gas exchange)
Ex. Lily
What are aerial roots?
Roots not is the soil (AIRial)
Ex. Orchids
What are contractile roots and what is an example?
They pull the plant deeper into the soil
Ex. Lily bulbs
What is a buttress root do and what does it look like?
It helps stabilize the tree, usually tropical and it looks like a wall
What are parasitic roots and what is an example?
They are plants that have no chlorophyll and are dependent of chlorophyll-bearing plants for nutrition
Ex. Dodder, Cancer root
What does Mycorrhizae form?
A mutualistic association with plant roots
A fungus is able to absorb phosphorus and other nutrients to give to the plant is exchange for photosynthesized sugars (food)
What are the two types of Mycorrhizae? Examples?
Ectomycorrhizae (outside the plant)
Ex. mushrooms
Endomycorrhizae (inside the cell)
Ex. Invade cell
What is important about the root nodules in a plant like clover?
There is a bacteria that produces enzymes that convert nitrogen into nitrates etc. Nitrogen-Fixing bacteria
What is the taxonomic name for the Legume Family?
Fabaceae
Through what interactions is soil formed? (6)
- cliimate
- parent material
- topography
- vegetation
- living organisms
- time
What does the solid portion of the soil consist of?
Minerals and organic matter
What are pore spaces?
Space between solid particles usually filled with air or water
What is Horizon A?
Topsoil
Dark, rich, and contains the most organic matter
What is Horizon B?
Subsoil
More clay, lighter in color
What is Horizon C?
Mineral soil
Not broken down into smaller particles
How do climates define soils?
Deserts: little weathering due to low rainfall
Grasslands: Moderate rainfall and well-developed soils
Rainforests: Excess rain and nutrients quick leave the soil
How does topography affect soils?
Steep areas can erode from wind or water
Flat areas can flood and contain little oxygen
What is the most desirable loam consist of?
40% silt, 40% sand, and 20% clay
What is wrong with coarse soils?
They drain water too quickly
What is wrong with dense soils?
They have poor drainage
In the upper 30 cm of agricultural soil, how much of the total soil weight do living organism make up?
1/1000th of the total weight
What do bacteria and fungus do in the soil?
Decompose organic material
What gives soil its dark color?
Humus, partially decomposed organic matter
What is hygroscopic water?
Water that is physically bound to soil particles and is unavailable to plants
What is gravitational water?
Water that drains out of pore spaces after is rains
What is capillary water?
Water held against the force of gravity in soil pores
What is field capacity?
Water remaining in the soil after drainage by gravity
What is permanent wilting point?
The rate of water absorption is insufficient for plant needs
What is available water?
Soil water between field capacity and the permanent wilting point
What is alkalinity?
It causes some minerals to become less available, add nitrogenous fertilizers
What does acidity inhabit?
The growth of nitrogen-fixing bacteria, add calcium or magnesium
Where is canopy soil found?
Temperate rain forests and tropical rain forests
What are the main differences between canopy and ground soil?
Canopy:
85% organic matter
Higher P
Lower Ca, MG, K, Fe, Mn, Cu, Zn, Al
Ground:
10% organic matter
Lower P
Higher Ca, Mg, K, Fe, Mn, Cu, Zn, Al
What is the difference between woody and herbaceous?
Woody: hard, secondary growth (Oak)
Herbaceous: soft (Dandelion)
What are most annuals?
Green and herbaceous and split monocot and dicot
Perennials are mostly
herbaceous
Herbaceous dicots have what?
Discrete vascular bundles of xylem and phloem
Alternate vs opposite leaf arrangements
Alternate means every other and opposite means directly across
Leaves attach at what?
A node
Between leaves (nodes) is what?
Internodes
What is a blade?
A flattened plant of the leaf
What is the blade attached to the twig by? (The little stem)
Petiole
What is the angle between the petiole and stem called?
The Axil
What is the bud located at the axil called?
Axillary bud
What is the bud at the tip called?
Terminal bud
Deciduous trees and shrubs have what?
Dormant axillary buds with leaf scars after leaves fall
What protects the apical meristem before the beginning of the growing season?
Bus scales and leaf primordia
The three tissues that the apical meristem develops are
The protoderm, pro cambium, and the ground meristem
What two things does the ground meristem include?
The pith and the cortex
What is the leaf primodia?
It is like a covering that acts as protection for the apical meristem before growing season
Cells produced by the vascular cambium become what?
Components of the secondary xylem and secondary phloem
What kind of plants are have the cork cambium?
Woody dicots because the cork cambium produces cork cells and phelloderm cells which is essentially bark
How many cells thick is the vascular cambium?
One
Which cell is produced by the vascular cambium and is pushed toward the outside?
Phloem
Which cell is produced by the vascular cambium and is pushed toward the inside?
Xylem
What is an annual ring?
One years growth of xylem
Large vessel elements of secondary xylem are called?
Spring wood
Smaller and fewer vessel elements of the secondary xylem are called?
Summer wood
What do vascular rays do and look like?
Lines across the rings and function in lateral conductions of nutrients and water
Mature bark can consist of what?
Alternating layers of crushed phloem and cork
What is heartwood?
Older, darker wood at the center of the trunk/stem
What is sapwood?
Lighter, still-functioning xylem closest to the cambium
Hardwood includes
Tracheas and vessel elements
Softwood includes
Tracheids, no fibers and vessel elements
Ex. cone-bearing trees
What are bulbs?
Large buds surrounded by numerous fleshy leaves, with a small stem at the lower end
Large buds surrounded by numerous fleshy leaves, with a small stem at the lower end
Bulbs
Corms
Resemble bulbs, but composed almost entirely of stem tissue
Resemble bulbs, but composed almost entirely of stem tissue
Corms
Cladophylls
Flattened, leaf-life stems
Flattened, leaf-life stems
Cladophylls
Thorns
Modified stems
Modified stems
Thorns
Tendrils
Vines
Vines
Tendrils
Rhizomes
Horizontal stems that grow below-ground
Horizontal stems that grow below-ground
Rhizomes
Runners
Horizontal stems that generally grow along surface
Horizontal stems that generally grow along surface
Runners
Stolons
Produced beneath the surface of the ground and tend to grow in different directions
Produced beneath the surface of the ground and tend to grow in different directions
Stolons
