Final Review Flashcards
What are the four points of all living things?
All living things…
- Require nutrients and energy
- Have and use DNA
- Are made of one or more cells
- Sense and respond to change
What are the three ways in which living things differ?
- Complexity of cell (prokaryote vs. eukaryote)
- Organization (unicellular vs. multicellular)
- Mode of nutrition (producer vs. consumer, ingestion vs. absorption)
What are the four parts of Cell Theory?
- All living things are made of cells.
- All cells come from pre-existing cells
- All cells contain DNA, at least at the start of their lives
- The cell is the basic unit of structure and function
“The cell is the basic unit of structure and function”
What does this mean?
Essentially, that it is the building block of life, and that it is the smallest unit which can perform the basic functions of life, i.e. do metabolism
What needs to be included on a microscopic drawing?
- Name of organism
- Magnification
- Measured scale
- Labels of all parts if possible
What do you look through on a microscope?
The eyepiece
What are the turny knobs on the microscope called?
Coarse and/or fine adjustment
Microscope:
What holds the many lenses?
The revolving nosepiece
Microscope:
What are the lenses closest to the specimen called?
Objective lenses
low-power, high-power
Microscope:
What acts like the aperture?
The diaphragm
Microscope:
What’s the light called?
Substage lamp
Microscope:
What holds the slide down?
Stage clip
Microscope:
Where do you place the slide?
On the stage
Microscope:
What is the name of the lens closest to your eye?
Ocular lens
What is a population?
All the inter-breeding members of the same species within a given habitat
What is a community?
A community consists of all the biotic components within a habitat, from algae to alligators
What is an ecosystem?
An ecosystem refers to a community interacting with its physical, abiotic environment
Are viruses alive?
No. They are not made of cells, for they lack both cytoplasm and the plasma membrane. But they’re damn close.
What/where is the nucleolus?
The centre part of the nucleus.
What/where is the nucleus?
The large centre brain of the cell
What/where is the rough ER?
The labyrinth connected to the nucleus, covered in ribosome bumps.
What/where is the smooth ER?
The tube-ish bits near the rough ER
What/where is the cell membrane?
The outside of the cell.
What/where is the lysosome?
The jelly bean organelle.
What/where is the mitochondria?
The organelle with the foldy bits inside.
What/where is the Golgi apparatus/body?
The pancakes.
What/where are the chloroplasts?
The stacks of green things.
What does the nucleolus do?
In charge of banging out ribosome parts
What does the nucleus do?
House and protects the DNA; the boss of proteins.
What does the rough ER do?
Assembles and organizes the proteins produced by the ribosomes.
What does the smooth ER do?
Produces lipids
What does the cell membrane do?
Guardian of the borders; selectively permeable, allowing only certain substances in and out
What does the lysosome do?
The recycling centre; takes care of intracellular digestion
What does the Golgi body do?
Sorts, packages, and labels the proteins; the post office.
What does the mitochondria do?
Tesla’s daydream, the hydro-dam; produces energy, i.e. ATP
Why do cells need to be small?
Cells are small so that their proportional surface area is larger, allowing for a better flow of substances across the membrane and better diffusion inside.
e.g. Too long for oxygen to diffuse means suffocation; for carbon dioxide it means poisoning.
What is passive transport?
Passive transport is the random movement of molecules from an area of high concentration to low concentration
What are two differences between plant and animal cells?
Plant cells have a cell wall and a gargantuan vacuole to to keep their structure. They also have chloroplasts to do photosynthesis.
Describe facilitated diffusion.
- Passive
- from high to low
- needs transport proteins
Describe active transport.
- Active
- from low to high
- requires ATP
- needs transport protein
What does hypotonic mean?
High water, low solute
What does hypertonic mean?
Low water, high solute
What are three kinds of passive transport?
- osmosis
- facilitated diffusion
- simple diffusion
How does osmosis differ from diffusion?
Osmosis is a kind of diffusion, but it is specifically water and always happens across a semi-permeable membrane
Explain how a protein is transported from the organelle that produces it to the ECF.
Ribosomes produce polypeptides which are then assembled through the rough ER. They move on through the small ER and bud off into vesicles that head over the the Golgi body. There, the are budded and absorbed through each successive layer of the Golgi body, which sorts, packages, and labels them for transport. Some are then budded off, destined for the membrane. At the membrane, the vesicles fuse with the use of ATP and protein membranes to perform exocytosis, aka they are actively transported to the ECF.
What is a producer?
Organisms that harvest energy directly from the environment, mostly through the process of photosynthesis in the chloroplasts.
What are consumers?
Organisms that mus obtain energy by eating/consuming other organisms, either parts, whole, remains, or wastes.
What is cellular respiration?
sugars + oxygen = released chemical energy + carbon dioxide + water
What is photosynthesis?
The process by which producers harvest sunlight and turn it into sugars/carbohydrates
Where does photosynthesis take place?
In the chloroplasts
Where does cellular respiration take place?
In the mitochondria
What forms does the flow of energy take?
light to chemical to heat
What is the difference between matter and energy in an ecosystem?
Matter cycles through an ecosystem whereas energy flows through and out, eventually lost through heat energy
What is the matter that gets cycled through an ecosystem?
Carbon dioxide, oxygen, nutrients, etc.
Interphase:
What are the three stages?
- Growth (G1)
- DNA synthesis (S)
- Preparation for division (G2)
Interphase:
What happens during growth?
The cell grows and produces more organelles
Interphase:
What happens during DNA synthesis?
Exactly what it sounds like–DNA is replicated
Interphase:
What happens during preparation for division?
Materials that will be needed for division are produced, i.e. proteins
What is the abbreviation for the phases of mitosis?
PMAT
What are the phases of mitosis?
Prophase
Metaphase
Anaphase
Telophase
Mitosis:
What happens in the prophase?
- nuclear membrane dissolves
- spindles form
- chromatin folds up and winds into visible chromosomes
Mitosis:
What happens during metaphase?
- chromosomes line up at the cell’s equator
- spindles attach to the centromeres
Mitosis:
What happens during anaphase?
- the spindles pull apart the sister chromatids and pull them toward the poles
Mitosis:
What happens during telophase?
- nuclear membrane reappears
- chromosomes uncoil
- cytoplasmic division has started
What are homologous chromosomes?
The same chromosomes but from different parents
How many sets of chromosomes does each cell have?
2 23 pairs (humans) 46 total (humans)
Meiosis:
What happens during prophase?
- nuclear membrane dissolves
- spindles form
- homologous pairs connect, forming tetrads
- crossing over occurs (mix those genes!)
Meiosis:
What happens to the sister chromatids during crossing-over?
The sister chromatids cross alleles so that they are no longer identical
Meiosis:
What happens during metaphase?
- tetrads line up at the equator
- homologous chromosomes are side by side
- paternal and maternal chromosomes are oriented randomly
What is the end result following meiosis II?
4 haploid, non-identical cells
Where does mitosis take place in my body?
- Hair or nail growth
- Repairing a broken bone
Where does meiosis take place in my body?
I’m a girl, so I get eggs in the ovaries
Which kingdom of life can reproduce both sexually and asexually?
Plants. They reproduce sexually with flowers and seeds, but you can also take a cutting and make an asexual copy of the original.
What are the advantages of sexual reproduction?
- creates genetic variation
- helps spread to a new environment
What is the advantage of genetic variation?
- affords protection from diseases
- allows for environmental adaptation
What are the disadvantages of sexual reproduction?
- takes a lot of time
- lots of energy
- requires two parents
- (in plants) requires a pollinator
What are the advantages of asexual reproduction?
- only needs one parent
- can expand quickly in favourable environments
- fast
- cheap, energy wise
What are the disadvantages of asexual reproduction?
- not much variation to protect against disease or environmental changes
- beneficial mutations are not passed on as quickly
- harmful mutations take longer to get rid of
How old is the Earth?
4.6 billion years
What are the steps of the scientific method?
- Observation
- Hypothesis
- Experimentation
- Analysis
- Theory
What is a hypothesis?
A testable explanation or model of something.
What is the point of experimentation?
To test/evaluate the hypothesis
What is analysis?
Decide whether the experiment supported or rejected the hypothesis (but never prove).
Not supported? Go back.
How is a theory formed?
It is only formed if supported by MANY experiments, e.g. Cell Theory, or Newton’s Laws of Motion
What are controls?
Variables that need to remain the same in an experiment so that the dependent variable can be properly assessed.
What is an independent variable?
The x-axis; the thing that we adjust so as to test the dependent variable.
What is a dependent variable?
The y-axis; the thing that will vary and that we are testing and measuring for.
In an experiment you need two groups; what are they?
The experimental group and the control group.
What is evolution?
Change over time, remember that it occurs in populations, not individuals.
Why does the age of the Earth matter in the theory of evolution?
Evolution takes a hella-long time, so for it to work, we need an Earth old enough to have supported life that long
What did Charles Lyell do for the theory of evolution?
His book, the Principles of Geology, proposed the theory of uniformity; essentially, he gave us an old Earth.
What is the theory of uniformity?
That gradual, repetitive geological processes shaped the Earth over great spans of time
What do we call the segments of DNA that decide traits?
Genes
What do we call variations of genes?
Alleles
What units (DNA) are passed down through generations and account for variation?
Alleles
How do alleles relate to evolution
The are the source/cause of random variation between individuals in a population
What do we call “leftover” organs or etc. in a species?
Vestigial structures
What are the four steps in random variation leading to natural selection?
- Variation occurs (alleles)
- Survival advantage
- Reproductive advantage
- Allele becomes more frequent in the population
What is comparative morphology?
Animals that seem different on the outside actually have similar internal structures, suggesting that they share a common ancestor.
What’s the kicker in comparative morphology?
Vestigial structures; i.e. Why would this organ (eg) have even developed if it wasn’t to be used?
What do we call similar structures in comparative morphology?
Homologous structures
What evidence does the fossil record give us?
Shit loads of extinction, showing that life has changed; and the layers show simpler organisms as you go further back in time.
What is the principle of superposition?
Younger fossils lie on top of older fossils
What is the dinosaur boundary called?
The KT Boundary
What is artificial selection?
Humans breeding dogs from wolves
What is speciation?
The formation of a new and distinct species in the course of evolution.
What is micro-evolution?
Micro-evolution occurs when variations (mutations) in alleles become frequent in a population
How do biologists explain the presence of the pharyngeal arches in human embryos?
Once upon a time, humans were little fishies that needed gills to breathe water. The pharyngeal arches are vestigial structures that help to demonstrate evolution at work.
What is reproductive isolation?
When two populations become separated via geological isolation and can no longer inter-breed
How could separated populations become two separate species?
Geographical separation means no more mutated allele swaps, so any variations are confined to the specific populations
What are the genes we all share that control our body plans?
Hox genes, short for homeobox
Why don’t we have more genes? If evolution goes from simple to complex, why don’t humans, for example, have hundreds of thousands of genes instead of just the 23,000-ish that we do have?
Hox genes help explain this. They are essentially construction project managers that direct the structural development of an organism by flipping on and off, almost like current switches. The key is that we all have the SAME ones. We started with the same and instead of adding more, the switches just flip. This does a lot to explain both macro- and micro-evolution
What is the order of biological classification mnemonic?
Dirty Kinky People Can Often Find Great Sex
What do protists have in common?
Mostly unicellular
All eukaryotes
Mostly live in water
What do animal-like and fungus-like protists have in common?
They are heterotrophs
How do animal-like protists get their nutrients?
They ingest to digest;
they are consumers or parasites.
How do fungus-like protists get their nutrients?
They digest outside and absorb nutrients.
How do plant-like protists get their nutrients?
They are autotrophic.
What is the “real” definition of a protist?
Any eukaryote that is not a plant, animal, or fungus
What’s another name for animal-like protists?
Protozoa or protozoans
Basically, what are the plant-like protists?
Algae
Basically, what are the fungus-like protists?
Decomposers
What’s that organelle that looks like a star?
The contractile vacuole
How does an amoeba move?
Using pseudopodia, false feet, which are extensions of the cytoplasm
How does a paramecium move?
Moves using cilia
How does a plasmodium move?
It doesn’t
What do amoeba eat?
Bacteria and other protozoans
How does an amoeba eat?
Phagocytosis. By surrounding and engulfing it; the food goes into the food vacuole with digestive enzymes.
Which organelle removes excess water?
The contractile vacuole
Name two protists that live in fresh water and have contractile vacuoles
Amoeba and protists
Why do freshwater protists need contractile vacuoles?
Although they live in fresh water, they are not made of fresh water; this means that they live in a hypotonic environment and water will naturally flow into them by osmosis. They contractile vacuole is a tool of homeostasis, allowing the organism to shuck excess water and return its inner environment to a favourable state.
What do we call the protective membrane that amoebas secrete when conditions are unfavourable?
Cysts
What sickness can amoeba cause in humans?
Amoebic dysentery from contaminated water
How does a paramecium eat?
The food comes in through a mouth pore, is moved into a gullet, and forms a food vacuole.
What is the rigid outer membrane of a paramecium called?
Pellicle
What are the advantages/disadvantages of the pellicle?
Can’t change shape, but offers more protection
How does a paramecium remove wastes?
Through the anal pore
What’s the kicker with paramecium?
They have two nuclei: macro- and micro-nucleus, used to reproduce sexually.
What does the macronucleus do in paramecium?
The normal job: controls protein synthesis, digestion, respiration, etc.
What does the micronucleus do in paramecium?
Used during conjugal visits
How do paramecium reproduce?
Two ways:
- Asexually (binary fission)
- Sexually (conjugation)
How does sexual reproduction work with paramecium?
Two paramecia join at the mouth pore; they then swap haploid micronuclei (that have undergone meiosis); these then form the macronuclei of the daughter cells after cells separate and each divides.
Which protist causes malaria in humans?
Plasmodium
How is plasmodium spread?
Through the anopheles mosquito
What’s a parasite?
An organism that lies on or in a host organism and causes harm to that organism
What’s a vector?
An organism that can carry a parasite and is responsible for infecting other organisms with that parasite
Why are plant-like protists so bloody important?
They produce shit tons of oxygen
What are three examples of plant-like protists?
Diatoms
Spirogyra
SOME euglena
What are euglena?
Mostly animal-like but occasionally plant-like protists
How do euglena move?
With a flagella
What physical feature puts euglena apart?
They have an eyespot.
What does the eyespot on a euglena do?
Senses light so it can places to photosynthesize
When do euglena become animal-like?
When they are kept in the dark and need to get energy as consumers
What are the main producers of oxygen in the oceans?
Diatoms
Why are diatoms so important in the ocean? (apart from the oxygen thing)
They are an important food source for marine animals, i.e. plankton
What sets diatoms apart physiologically?
They produce thin cell walls of silica
What do we call pond scum, aka multicellular algae?
Spirogyra
Spirogyra have bucket loads of what?
Chloroplasts
Are spirogyra multicellular organisms?
No, they are long filaments of cells connected end-to-end
Where do you find spirogyra and what do they look like?
They appear as slimy green mats on the surface of clean, nutrient-rich water; literally, this is pond scum
What is the common name for fungus-like protists?
Water mold
How do fungus-like protists work?
They form a mesh of nutrient-absorbing filaments.
How do euglena get their nutrients?
Photosynthesis and consumption of bacteria and smaller protists.
What are the 8 main parts of bacteria/archaea?
Cell wall Capsule Plasma membrane Cytoplasm Flagellum Pilus DNA Ribosomes
What are the five types of archaea?
Chemosynthetic Photosynthetic Halophiles Methanogens Thermophiles
What are chemosynthetic bacteria?
They use chemicals to obtain energy and are found on the ocean floor.
What are thermophiles?
Bacteria that live in hot springs, lava, etc.
What do we call the group of bacteria that do cellular respiration without oxygen?
Obligate anaerobes
What are halophiles?
Bacteria that live in salty environments
What are methanogens?
Bacteria that live in animal guts and sewage treatment plants, and produce methane gas
What do we call bacteria that get energy from dead organisms (decomposers)?
Saprophytes
How do most bacteria obtain energy/nutrients?
They are heterotrophs
What do we call bacteria that get food from living organisms without killing them?
Parasites
What is another name for photosynthetic bacteria?
Blue-green algae
What are sphere-shaped bacteria called?
Cocci
What are rod-shaped bacteria called?
Bacilli
What are spiral-shaped bacteria called?
Spirilli
What do we call bacteria that cluster?
Staphylo
What do we call bacteria that chain?
Strepto
How do bacteria stick together?
The sticky capsule!
Which virus causes shingles?
Varicella zoster virus
What are the symptoms of shingles?
A painful rash that develops on one side of the face or body. The rash forms blisters that typically scab over in 7 to 10 days and clears up within 2 to 4 weeks. Other symptoms: - Fever - Chills - Headache - Upset stomach
How is shingles transmitted?
4 points
- Shingles cannot be passed from one person to another.
- The varicella zoster virus, can be spread from a person with active shingles to another person who has never had chickenpox. In such cases, the person exposed to the virus might develop chickenpox, but they would not develop shingles.
- The virus is spread through direct contact with fluid from the rash blisters caused by shingles.
- A person is not infectious before the blisters appear. Once the rash has developed crusts, the person is no longer contagious.
What is the best treatment/prevention for shingles?
There is a shingles vaccine and people over 60 are recommended to get it.
There are several antivirals for treatment, but to be effective, they must be started as soon as possible after the rash appears.
Pain medicine, calamine, and oatmeal baths can help with the pain and itching.
Which bacteria cause ulcers?
Helicobacter pylori
How do bacteria reproduce?
Mostly asexually
What’s it called when cells split?
Binary fission
What’s up with the DNA in bacteria reproduction?
There’s a single strand of DNA that gets replicated; there are no chromosomes.
What’s up with bacteria conjugation?
Plasmids are transferred through a cytoplasmic bridge formed by a pilus
What’s a plasmid?
A small, separate, circular piece of DNA
What are some advantages to bacteria?
- They are part of food for us
- Symbiotic relationship with plants
- They decompose waste
- They recycle nutrients (complete the loop)
- Help digest food
What are some disadvantages of bacteria?
- Kill our species in the millions
- Destroy food and property
- Create general unpleasantness such as bad breath, acne, etc.
What are the basic parts of viruses?
They are basically just DNA/RNA surrounded by protein
What is the protein coat of a virus called?
Capsid
What are two other things that a virus might have?
Enzymes to help it inject DNA into the host, and an envelope formed of little bits of membrane they steal from the host.
Why aren’t viruses alive?
four points
- They don’t do homeostasis
- They do not do cellular respiration
- They do not grow or develop
- They cannot reproduce on their own
What life-like qualities do viruses have?
- They do reproduce, just not on their own
- They evolve/mutate
- They have limited movement
What are the four types of viruses?
Bacteriophages
Adenoviruses
Retroviruses - RNA viruses
DNA viruses
What are bacteriophages?
Viruses that infect bacteria; they can be considered helpful because they kill bacteria that can harm us
What are adenoviruses?
Infects animals; causes eye infections, common colds, hepatitis, etc.
What is the structure of an adenovirus like?
It has a 20-sided protein cot with a spike at each corner
What are retroviruses?
RNA viruses that have an enzyme called reverse transcriptase which converts RNA to DNA inside host cells
What do retroviruses cause?
Influenza, rabies, AIDS
Which viruses have lipid envelopes?
RNA and DNA viruses
What do DNA viruses cause?
Smallpox and herpes
What are the two virus cycles in bacteriophages called?
Lytic and lysogenic
Which cycle kills the host cell?
The lytic cycle
What are the five stages in the lytic cycle?
- Attachment
- Penetration
- Replication + Synthesis
- Assembly
- Release
What does “lysic” actually mean?
The “breaking” of the cell; BOOM!
How do the lytic and lysogenic stages differ?
There is no synthesis of parts in the lysogenic cycle; the virus basically remains dormant until the time is right, then BAM!
What’s the difference between prokaryotes and eukaryotes?
Prokaryotes have only a simple DNA molecule which (unlike in eukaryotes) does not coil into chromosomes and is not surrounded by a nuclear membrane.
What is the difference between archaea and bacteria?
Archaea are older and found in more extreme environments
What are cyanobacteria sometimes classified as plants?
They carry out photosynthesis: they fix carbon from CO2 into organic compounds and produce oxygen.
Describe binary fission
The DNA molecule of a bacterium is replicated and the two molecules are separated by membrane and wall material while it continues to grow. When it has almost doubled in size, the new membranes and walls between the DNA molecules are completed and two identical cells result
Why are bacteria important for our digestion?
They break down certain food molecules and produce vitamins, including vitamin K
What structure protects bacteria?
The capsule offers some protection against things like white blood cells
What is a bacterium’s capsule made of?
Sticky polysaccharides
What are the function of pili?
They help bacteria cling to surfaces, and sex pili enable conjugation
Distinguish between the lytic and lysogenic pathways.
In the lytic pathway, the virus uses the host cells to reproduce, then kills the cell.
In the lysogenic cycle, the viral DNA is inserted into the host DNA molecule and is duplicated along with host DNA when cells divides.
What are the two main differences between the lytic and lysogenic pathways?
Viral proteins are made vs. not made
Cells are killed vs. not killed
Do viruses and bacteria cause disease in the same way?
No. Viruses hijack the host cell and prevent the cells from functioning properly, whereas bacteria invade human tissues and cause disease through the toxic substances they produce and release.
What is mutualism?
Mutualism is a species interaction in which each species benefits by associating with the other.
What is obligate mutualism?
It means that the two species literally need each other, e.g. milkweeds and monarchs
What is mutual protection?
When the two species use each other for protection, e.g. the clown fish and anemone
What are competitive interactions?
Essentially, resource wars.
Since resources are scarce and limited, there is major competition for them.
What is an ecological niche?
The environmental conditions under which an organism can survive and thrive.
What is resource partitioning?
The evolutionary process by which species adapt to share resources in a way that limits competition.
What is predation?
An species interaction in which one species (predator) captures, kills, and eats another species (prey).
What is ecological succession?
A process in which one array of species replaces another
What is primary succession?
When NOTHING was there, e.g. new volcanic land or glaciers receding
What is a pioneer species?
The first species to appear in a primary succession, usually lichen or mosses
What do pioneer species do?
They are opportunistic colonizers that help to build and improve soils
How do lichens create soil?
They lichen breaks down the rock, producing organic materials; other organic matter blows in with the wind, and soil is formed.
What is lichen?
A form of mutualism with a pairing of fungus and algae/cynobacteria
How do the fungus benefit in lichen?
The algae and cynobacteria do photosynthesis; the algae makes sugars
How do the algae/cynobacteria benefit in lichen?
The fungus absorbs minerals from breaking down the rock and retains water (otherwise they’d just dry up)
What is a secondary succession?
When one array replaces another in a disturbed region, e.g. the OK Mtn Park fire
Who developed the taxonomic categories?
Carl Linnaeus
Our system of naming uses two names–what’s that called?
Binomial nomenclature
What is taxonomy?
The science of classification
How many known, living, and named species are there on Earth?
2 - 4.5 million
How many estimated species are there on Earth?
10 - 100 million
How many species is it estimated that we lose a year?
50 000
How is a species defined?
Organisms with similar characteristics that produce fertile offspring
What is the problem with our current definition of a species?
We run into problems with unicellulars that reproduce asexually.
What is a dichotomous key?
A key for the identification of organisms
What are the three domains?
Archaea, Eubacteria, Eukarya
What are the five kingdoms?
Monera, plantae, fungi, protista, animalia
What is the underground part of a fungus called?
The mycellium network
What does the mycellium do?
They look for molecules to break down.
Where do fungi live?
In warm,dark, moist conditions rich in organic matter
What are the benefits of fungi?
- They decompose and recycle nutrients
- Mycorrhiza helps trees and other plants absorb water and nutrients from the soil
- Lichens make soil
- Food: mushrooms and blue cheese
- Baking and brewing: yeast
- Antibiotics: penicillin
What are the negatives of fungi?
- Fungal crop parasites spoil food
- Mold damage to homes
- Parasites on humans, e.g. athlete’s foot
What is mycorrhiza?
It is a symbiotic relationship between fungi and the roots of vascular plants.
What do fungi get from mycorrhiza?
They get sugars (carbohydrates/energy) from the plants
What do plants get from mycorrhiza?
They gain nutrients and water from the soil
What are hyphae?
They are the long, branching filaments in the fungi underground network, collectively called the mycelium network
What do hyphae do?
They search out and digest food
Where do hyphae come from?
They grow from a single spore (mitosis)
How do fungi break down food?
Externally; they secrete digestive enzymes onto food, then absorb the resulting small food molecules
Describe the life cycle of fungi.
- Haploid spore (n) grows into the hyphae
- Undergoes cytoplasmic fusion
- Now in the dikaryotic state (n + n)
- Grows into fruiting body
(in the cut out of the gill) - undergoes nuclear fusion (2n), fertilization
- Undergoes meiosis
- Now back to haploid (n) spore to be blown in the wind
What are the four major events in the evolution of land plants?
- Zygote protection and waxy cuticle
- Vascular tissue
- Pollen grain and seed
- Fruits and flowers
What’s the biggest difference between plants, fungi, and animals?
Animals: diploid dominant
Plants: alternation of diploid and haploid generations
Fungi: dikaryotic stage
What plants are associated with the first major event in the evolution of land plants?
Bryophytes
What plants are associated with the second major event in the evolution of land plants?
Seedless vascular plants
What plants are associated with the third major event in the evolution of land plants?
Gymnosperms
What plants are associated with the fourth major event in the evolution of land plants?
Angiosperms
What plants are bryophytes?
Mosses
What are the characteristics of bryophytes?
Short, no true leaves and no real roots; only found in moist habitats
Why doesn’t moss grow tall?
- It has no way of transporting water up and down
- It would fall over (no vascular tissue)
Why do bryophytes need moist environments?
It can only sexually reproduce in water; the sperm must “swim” to the egg
What plants are “seedless vascular plants”?
Ferns, horsetails, etc.
What are the characteristics of seedless vascular plants?
- has roots
- grows to over 30 cm
- stem walls show channels in cross-section
What do seedless vascular plants have in common with bryophytes?
Still cannot reproduce in dry environments
What kind of plants are gymnosperms?
Conifers
What are the characteristics of gymnosperms?
- Seeds!
- Pollen grains travel through the air from male to female structures and gametes meet after arrival (never exposed to air)
- Seed allows dispersal of protected embryo (increased survival rate of offspring)
What kind of plants are angiosperms?
Maples, roses, dandelions, etc.
This is by FAR the most diverse group.
What is the point of fruit?
A fruit covering protects seeds and attracts animals; animals eating fruits disperse seeds in the feces
What is the point of flowers?
The colours and nectar attract insect and bird pollinators who carry pollen grains along as they travel from one flower to the next, effecting pollination
Flower parts: What’s the peener/tube part called?
Carpel
Flower parts: The thing that looks like a petal but isn’t
Sepal
Flower parts: What holds the stigma, style, and ovary?
Pistil
Flower parts: Hole at the top of the pistil
Stigma
Flower parts: Tube of the pistil
Style
Flower parts: Tank of the pistil
Ovary
Flower parts: Eggy bits
Ovule
Flower parts: Stem of the stamen
Filament
Flower parts: Pollen sack of the stamen
Anther
Flower parts: Lady bits
The pistil
Flower parts: man bits
The stamen
