Flashcards in Plants and the colonization of land Deck (62):
almost always used to ward off attack of virus, predators, the plant doesn't need it to survive directly but uses this as protection from the world
Why are plants important?
drugs and medicine
conversion of the sun's energy
what is the basis of agriculture
How does a bee help plants reproduce?
it acts as a messanger, carrying the pollen containing sperm from male flowers to female flowers hich receive the sperm
where are female and male flowers located on a plant and why?
The female flowers are towards the bottom of the plant as flowers can turn male after growing for a while so the younger flowers at the base of the plant are female
What is the study of plants called?
What is our definition of a plant?
charophytes (green algae)
chlorophytes (green algae)
embryophytes (land plants)
What is it called when a non-photosynthetic eukaryote engulfs a photosynthetic cyanobacterium (a prokaryote, now called a plasmid)?
What is it called when a non-photosynthetic eukaryote engulfs a photosynthetic eukaryote?
what are the types of photosynthetic eukaryotes?
red and green algae
Explain the oxygen revolution
no oxygen in atmoshphere
- organisms (cyanobacteria) took in CO2 which was plentiful
-air became so oxygen dense it became toxic for some
- oxygen helped create ozone layer, life slowly moved to land
- natural give and take of CO2 and oxygen we have today
What happened 4550 million years ago
the earth formed
what appeared 3500 million years ago
What are the two things that happened 1500 million years ago?
First plasmid was engulfed by eukaryote
red and green algae diverge
When did the colonization of land begin
500 million year ago
What are the shared features of all plants in this course ?
1) they use starch as energy
2) they all contain chlorophyll b
3) cellulose is a major component of the cell wall
4) thylakoids are in stacks called grana
What are the shared features of land plants and charophytes/ what are the features of land plants ancestors?
1) cells begin dividing from inside, not outside
2) plasmodesmat, the connection between cells
3) sperm structure
4) rose-shaped cellulose synthesizing complexes
6) peroxisome enzymes
What are features of land plants/ embryophytes that seperate them from other plants in this course?
1) the cuticle
2) jacketed sex organs called gametangia
3) embryophyte condition
4) alternation of generations
Why do plants use starch as energy and not sugar?
Sugar is a good storage molecule because it is easily metabolised and not very reactive, however they absorb and retain water. Starch are chains of glucose so starch can be easily be broken into sugar and starch is insoluble so no water problem
what is chlorophyll b
chlorophyll b is an accesory pigment that passes enrgy to chlorophyll a which all photosynthetic eukaryotes have
what is unbranched rediues of glucose?
what is amylose?
straight chain residues of glucose, 20% of starch in plants
what is amylopectin?
branched linked residues of glucose, 80% of starch in plants
what is the most common organic polymer on earth?
What makes grana green?
chlorophyll which is contain in thylakoids
what ar stacked to make grana?
what are thylakoids?
membranes inside chloroplast
How do we know that charophytes are the closest relative to embryophytes?
nuclear and chloroplast genes
what starts the dividing process in charophytes and embryophytes?
First the formation of the cell plate
What is the cell plate associated with?
what is a phragmoplast? what is it made of?
the thing that pulls the cell apart, made of microtubules associated with the cell plate
What are the connections between cells of embryophtes and charophytes called?
what are plasmodesmata?
cell membrane extentions through pores in cell wall
What does the plasmodesmata allow to pass from cell to cell?
what is a peroxisome and its purpose?
an organelle involved with detoxifying
What is referred to as " the most durable organic product on earth"?
sporopollenin; an organic polymer
What does sporopollenin do in nature?
prevents drying out of plants by covering spores and protects embryophytes and charophytes from attacks from viruses and bacteria
What is the waxy covering that prevents the drying out of land plants called?
what are land plant sex organs called?
what are male land plants sex organs called and what do they produce?
antheridium ; produces sperm
what are land plants female sex organs called and what do they produce?
gametangia produce through what process and why?
mitosis as they are already haploid (n)
Why are embryophytes named embryophytes?
the embryophyte condition
What is the embryophyte condition?
egg/gamete stays on maternal tissue, is fertilized there by males gamete/ sperm , and then the zygote grows on mom and is eventually released
What odd phenomenom only occurs in sexual organisms?
alternation of generations
what process makes diploid haploid
What process makes haploid diploid?
What is special about land plants/ embryophtes sexual reproduction?
both phases of life are multicellular
what or which share the feature that they use starch as energy?
all of plants in this course
which or what have a cuticle?
just land plants/ embyrophytes
what or which divde from the inside of the cell starting at the cell plate and using phragmoplast?
both the charophytes and the embryophytes
which or what contains chlorophyll b ?
all plants in this course
what or which have jacketed sex organs (gametangia )?
only land plants
what or which has cellulose as a major component of the cell wall?
all plants in this course
which share the same sperm structure?
embryophytes and the charophytes
what or which has rose-shapes cellule synthesizing complexes?
what or which has the embryophte condition?
what or which has sporopollenin, the most durable organic product in the world?
what or which has alternatino of generations?
what or which have thylakoids in stacks called grana?
what or which have peroxisome enzymes?