Lecture Exam 2 Flashcards

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1
Q

In a eukaryote cell, the nucleus and endomembrane system is believed to be derived from

A

archaea ancestor

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2
Q

In a green algae cell, the chloroplast is believed to be derived from

A

cyanobacteria

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3
Q

In a eukaryote cell, the mitochondrion is believed to be derived from

A

proteobacteria

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4
Q

In a brown algae, diatom or dinoflagellate cell, the chloroplast is believed to be derived from

A

early red algae

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5
Q

In life cycles with an alternation of generations, multicellular haploid forms alternate with

A

multicellular diploid forms.

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6
Q

Eukaryote cells can reproduce by

A

Mitosis and Meiosis

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7
Q

Chloroplasts and mitochondria reproduce by

A

Binary fission

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8
Q

Water molds, Brown Algae, Dinoflagellates and Diatoms belong in the super group

A

“SAR”

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9
Q

A single haploid cell for dispersal describes a _______________ in a plant lifecycle.

A

spore

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10
Q

How are Antheridia and Archegonia poduced in the life cycle of mosses?

A

Antheridia and archegonia are produced by gametophytes.

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11
Q

Four major theories in Biology

A

Cell, Gene, Heredity and Evolution

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12
Q

Law vs. Theory vs. Dogma

A

Theory – comprehensive explanation, useful to
hypothesize to other conditions

Laws describe a physical phenomenon, limited
to set conditions cannot be hypothesized
outside those conditions

Dogma is not tested – beliefs

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13
Q

explain the theory of evolution by natural selection, giving details to the steps: populations, genetic diversity, resources, fertility, struggle, change over time, new species

A

Populations have variation in traits (phenotypes)
among individuals and they evolve not individuals
Genetic diverstiy: This variation comes about by recombination of genes in sexual reproduction, Mutation forms new traits, then these traits are heritable (genetic)
Resources: Resources in the environment at some point become limited, Population’s own growth exceeds resources, A novel trait or behavior forms, New predator or disease moves in, Climate changes, droughts etc.
Fertility: Populations have a greater fertility than their environment can sustain
Struggle: There is a struggle / competition to survive among the offspring.
Species: Species evolve to be suit the environment

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14
Q

Place these events in the origins of the eukarya in order of occurrence, earliest to most recent:

Formation of mitcochondria
Formation of chloroplast from
Formation of nucleus and endomembrane system
Formation of chloroplast from

A

Formation of nucleus and endomembrane system
Formation of mitcochondria
Formation of chloroplast from cyanobacteria
Formation of chloroplast from an algal cell

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15
Q

In evolutionary terms, a group with a trait that is “better fit” _________.

A

leaves more fertile offspring into future generations

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16
Q

The scientific method can be used to solve problems or answer questions that can be _____.

A

be measured using physcial properties

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17
Q

Analogous traits in two species ___________.

A

have the same functions and do not show common ancestry.

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18
Q

In convergence

A

different species adapt to similar environments.

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19
Q

How would you properly identify (describe) a bacteria with a round shape and grows in pairs?
coccus
bacillus
streptococcus
streptobacillus
staphlococcus
staphlobacillus
diplobacillus
diplococcus

A

diplococcus

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20
Q

Prokaryotes’ essential genetic information is located in the

A

nucleoid/genophore.

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21
Q

Which term describes a prokaryote that obtains both energy and carbon as it decomposes dead organisms?

A

chemoheterotroph

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22
Q

Bacterial cell walls are composed of _______.
peptidoglycan
chitin
cellulose
starch
pectin

A

peptidoglycan

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23
Q

Which is not a prokaryote feature?
Cell wall
Plasma membrane
Chromosome
Ribosome
Flagella
Mitochondria

A

Mitochondria

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24
Q

A nonessential gene in a bacteria that is present in only some of the individuals in a population (such as antibiotic resistance) most probably would be found in the ______.
pilli
genophore/nucleoid region
chromosome
plasmid
nucleus

A

plasmid

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25
Q

In a process called _______________ bacteria take in atmospheric nitrogen and produce ammonia.

A

nitrogen fixation

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26
Q

In transformation bacteria_______________.

A

take in free DNA from their environment.

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27
Q

Cells ( and some organelles) reproduction- match the cell type with the division process

Prokaryotes ( Bacteria and Arcahe)
Eukaryote - One cell goes to 2 identical cells
Eukaryote- one (2n) diploid cell goes to 4 (n) haploid cells all distinct
Chloroplasts and Mitochondria

Options:
Meiosis
Binary Fission as independent
Mitosis
Binasry fission inside a eukaryotic cell

A

Binary Fission as independent cell
Mitosis
Meiosis
Binasry fission inside a eukaryotic cell

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28
Q

Cell theory

A

All living organisms are made of cells

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29
Q

Gene Theory

A

how traits are passed from one generation to the next and provides a foundation for our understanding of heredity.

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30
Q

Heredity and Evolution

A

heredity is concerned with the transmission of genetic information from one generation to the next, while evolution deals with the long-term changes and diversification of species over geological time scales.

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31
Q

What are some examples supporting the theory evolution

A

Fossil Record,Comparative Anatomy, Embryology, Biogeography, Molecular Biology, Vestigial Structures, Observational Evidence ,Transitional Forms, Convergent Evolution, and Experimental Evolution

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32
Q

Artificial Selection

A

human designed breeding of plants and animals for desired
traits by selecting which individuals get to reproduce.

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33
Q

adaptation

A

where organisms evolve and acquire characteristics or traits that enable them to better survive and reproduce in their specific environment. Adaptations are the result of natural selection

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34
Q

biogeography

A

where species are found around the globe

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35
Q

Homologous / analogous structures

A

Homologous: Show common ancestry, Derived from a common ancestral structure, May have specialized into different functions
Analogous: Have same functions ( by convergence), Do not have a common ancestry, and are not derived from the same ancestral feature

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36
Q

Evolutionary convergence

A

where unrelated or distantly related organisms independently evolve similar traits, characteristics, or adaptations in response to similar environmental or ecological pressures.

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37
Q

What is Fitness?

A

is the ability to have more offspring (frequency
of genes in the genepool)

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38
Q

What are conserved traits?

A

where genes mutate slowly, used to show distant relationships. (characteristics, features, or genetic sequences that have remained relatively unchanged or stable over long periods of evolutionary time)

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39
Q

How do we measure fitness between species? or traits?

A

Measured with interactions with other species, environmental conditions, and genetic variation.

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40
Q

Linnaeus

A

*Developed modern taxonomy: grouping organism in a
logical manner
* Made Binomials: Homo sapiens
* Based groupings on morphology
* Did not believe in evolution,
* Taxonomy data would later provide some of
best evidence

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41
Q

Lyell

A

British geologist.
* Following Hutton’s work
* Earth is old
* Valleys formed by erosion
* Mountains by uplifting
* Slow processes over long periods of time
* Mechanisms of change are constant over time

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42
Q

Malthus

A

British economist studied Paris after the French
revolution:
* Limited resources
* Excess population growth
* Population had to struggle to survive,
* Competition among individuals
* Survival of the richest

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43
Q

Lamarck

A
  • Said species evolved to be better suited to
    environment – right!
  • But- got the genetics wrong
  • Stressed inheritance of acquired traits-(wrong),
    and use and disuse
  • Giraffes stretched their necks making Baby giraffes have longer necks
  • Others also with hypotheses- a series of people trying to figure it out
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44
Q

How did Lamarck’s theory help Darwin formulate his theory?

A

By saying Species evolve to be suit the environment

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45
Q

Phylogenetic trees

A

are diagrammatic representations of the evolutionary relationships among a group of organisms or species. They depict the branching patterns of ancestral and descendant lineages to describe evolutionary history

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46
Q

Monophyletic

A

describe a group of organisms that includes a common ancestor and all of its descendants. also known as clades or natural groups,

47
Q

polyphyletic

A

describe a group of organisms that includes multiple species or taxa that do not share a recent common ancestor.

48
Q

paraphyletic

A

describe a group of organisms that includes a common ancestor and some, but not all, of its descendants.

49
Q

Holotype

A

a single physical specimen or individual organism that is designated as the primary reference point for a newly described species

50
Q

binomials

A

is a standardized system for naming and classifying species, such as genus and species

51
Q

Classification vs. Systematics

A

classification is concerned with organizing organisms into hierarchical groups based on shared characteristics.
Systematics focuses on understanding the evolutionary relationships and history of organisms, use to build phylogenetic trees.

52
Q

Biological taxa levels:

A

Domain, Kingdom, Phylum, Class, Order, Family, Genus species

53
Q

analogous traits

A

characteristics or features found in different species that have a similar function or appearance but did not arise from a common ancestral origin.

54
Q

homologous traits

A

characteristics or features found in different species that share a common ancestry and evolutionary origin.

55
Q

convergence

A

the independent evolution of similar traits, features, or characteristics in unrelated species or lineages.

56
Q

Binary Fission

A

a method of asexual reproduction commonly used by single-celled organisms, particularly prokaryotes such as bacteria and archaea.

57
Q

Cell wall composition

A

Bacterial Cell Walls: Peptidoglycan
Archaeal Cell Walls:Diverse Compositions
Fungal Cell Walls: Chitin
Algal Cell Walls: Cellulose
Plant Cell Walls: Cellulose, Hemicellulose, Pectin, and Lignin

58
Q

Genome (prokaryote)

A

set of genetic material, including all the genes, DNA, and associated sequences, contained within an organism’s chromosomes. Represents blue print

59
Q

eukaryotic vs. prokaryote flagella

A

Prokaryotic flagella are simpler in structure, rotate like propellers, and are primarily composed of flagellin. Eukaryotic flagella are more complex, exhibit bending movements, and have a 9+2 microtubule arrangement composed of tubulin protein subunits.

60
Q

taxis (prokaryote)

A

DirectedMovement towards or away from a stimulus.
way from a stimulus.
light (phototaxis)
chemical (chemotaxis)
magnetic field (magnetotaxis)
Positive taxis movement toward a stimulus.
Movement away from a stimulus is a negative taxis

61
Q

difference between cell membrane and cell wall

A

cell membrane is a semi-permeable barrier that controls the passage of molecules in and out of the cell and is found in all types of cells. The cell wall is a rigid, protective structure primarily found in plant, fungal, bacterial, and some protist cells, and its main function is to provide support and protection to the cell.

62
Q

gram positive and negative bacteria- dye response & structure

A

the Gram stain response is determined by the thickness and composition of the cell wall. Gram-positive bacteria retain the crystal violet-iodine complex due to their thick peptidoglycan layer, while Gram-negative bacteria do not retain it as effectively because of their thin peptidoglycan layer and the presence of an outer membrane.

63
Q

Nucleoid (genophore)

A

usually one double-stranded, circular DNA molecule in prokaryotes

64
Q

plasmids

A

Smaller independent rings of DNA
- “extra genes” -antibiotic resistance or metabolism of
unusual nutrients.
- Replicate independently of the nucleoid chromosome.
- Can be transferred between partners during
conjugation
- Also found in yeasts, (fungi=eukaryotes)

65
Q

endospores

A

serve as a survival mechanism that allows bacteria to endure unfavorable environmental conditions, such as extreme heat, desiccation (lack of water), radiation, and exposure to toxic chemicals or disinfectants.

66
Q

microevolution in progress - how/why is it happening?

A

microevolution is happening continuously due to the interplay of genetic variation, selection pressures, genetic drift, gene flow, and environmental changes.

67
Q

Transformation

A

which bacteria take up DNA from their external environment and incorporate it into their own genome

68
Q

Conjugation

A

transfer of genes from one bacterium to another, usually of same species.

69
Q

Transduction

A

transfer of genes between bacteria via viruses (bacteriophages).

70
Q

photoheterotroph

A

is an organism that uses light as an energy source but cannot fix carbon dioxide (CO2) into organic compounds

71
Q

obligate anaerobe

A

Can not live in the presence of oxygen

72
Q

Obligate aerobes

A

Must have Oxygen to live

73
Q

Facultative anaerobes

A

Prefer Oxygen and Can survive with little or no O2 by fermentation.

74
Q

Facultative aerobes

A

grow and thrive in the presence or absence of oxygen (O2)

75
Q

Fermentation

A

a metabolic process that occurs in the absence of oxygen (anaerobic conditions) in which microorganisms, such as bacteria, yeast, and some fungi, convert organic compounds into simpler substances.

76
Q

Heterotrophic

A

organisms that obtain their organic carbon and energy by consuming other organic matter

77
Q

Phototrophic

A

organisms are those that use light energy to drive the synthesis of organic compounds from inorganic sources

78
Q

decomposers

A

organisms in an ecosystem that play a crucial role in breaking down and recycling dead organic matter

79
Q

saprobes

A

are decomposers that absorb nutrients from dead organic matter.

80
Q

nitrogen fixation - why do organisms (autotrophs especially) need nitrogen?

A

most autotrophic organisms cannot use atmospheric nitrogen directly. Instead, they rely on nitrogen compounds like ammonia (NH3), nitrate (NO3-), and nitrite (NO2-) that are available in the soil or water. It is crucial for autotrophs because it is essential for building important biomolecules like proteins, nucleic acids, and chlorophyll

81
Q

what characters distinguish archaea them from bacteria. (cell
wall material, cell membrane)

A

Cell Wall Composition:

Bacteria: Most bacteria have cell walls primarily composed of peptidoglycan, a complex polymer made of sugar and amino acids.
Archaea: Most archaeal cell walls lack peptidoglycan entirely. Instead, archaeal cell walls are made of various substances, including pseudopeptidoglycan (in some methanogens) or other unique polysaccharides and proteins.
Cell Membrane Structure:

Bacteria: Bacterial cell membranes are typically composed of lipids called glycerophospholipids. In bacterial cell membranes, the glycerol backbone of these lipids is linked to fatty acid chains.
Archaea: are composed of ether-linked isoprenoid chains (isoprenoid glycerol diethers or isoprenoid glycerol tetraethers).

82
Q

Archaea- types/habitats

A

Methanogens: Use H2 to reduce C02 to CH4 and are strict
anaerobes - In Digester at treatment plant
Extreme Halophiles: inhabit high salinity ( 15-20%) environments
(e.g. Dead Sea)
Extreme Thermophiles: Live in habitats of 60 - 80°C

83
Q

Virus

A

need to infect a living cell to get reproduced

84
Q

Prions

A

rogue free proteins (Mad cow disease)

85
Q

Viroids

A

naked RNA (Coconut Tree disease)

86
Q

Nucleus

A

membrane-bound organelle found in eukaryotic cells. It serves as the control center of the cell,

87
Q

organelles

A

membrane-bound structures found within eukaryotic cells. Nucleus: The nucleus is the control center of the cell, housing the cell’s genetic material (DNA) and directing cellular activities. It regulates gene expression and contains the nucleolus, where ribosomal RNA (rRNA) is synthesized.
Such as (not needed to memorize only the organelles itself):

Endoplasmic Reticulum (ER): The ER is a network of membranes involved in protein synthesis, lipid metabolism, and detoxification. There are two types: rough ER, which has ribosomes on its surface, and smooth ER, which lacks ribosomes.

Ribosomes: Ribosomes are small, non-membranous organelles responsible for protein synthesis. They can be found attached to the rough ER or free in the cytoplasm.

Golgi Apparatus: The Golgi apparatus is involved in modifying, sorting, and packaging proteins and lipids for transport within or outside the cell. It consists of flattened membrane sacs called cisternae.

Mitochondria: Mitochondria are the energy powerhouses of the cell, where cellular respiration takes place, converting glucose and oxygen into ATP (adenosine triphosphate), the cell’s primary energy source. Mitochondria have their own DNA.

Chloroplasts: Chloroplasts are found in plant cells and some protists. They are the sites of photosynthesis, where light energy is converted into chemical energy (glucose) using chlorophyll. Like mitochondria, chloroplasts have their own DNA.

Lysosomes: Lysosomes contain enzymes that break down cellular waste, cellular debris, and foreign materials. They are responsible for cellular digestion and recycling.

Peroxisomes: Peroxisomes contain enzymes that break down fatty acids and detoxify harmful substances, such as alcohol and hydrogen peroxide.

Vacuoles: Vacuoles are membrane-bound sacs responsible for storage, regulation of cell turgor pressure (in plant cells), and the digestion of cellular waste. In plant cells, the central vacuole is particularly large and important.

Cytoskeleton: The cytoskeleton is a network of protein filaments (microfilaments, intermediate filaments, and microtubules) that provides structural support, helps in cell movement, and aids in intracellular transport.

Centrioles: Centrioles are cylindrical structures involved in cell division. They organize microtubules during cell division and are found in animal cells.

Nucleolus: The nucleolus is a substructure within the nucleus responsible for the synthesis and assembly of ribosomal RNA (rRNA) and ribosomal subunits.

Endosomes: Endosomes are involved in the sorting, processing, and trafficking of molecules, such as membrane receptors and ligands, within the cell.

Flagella and Cilia: Flagella and cilia are hair-like projections on the cell surface that are involved in cell motility. Flagella are typically longer and fewer in number, while cilia are shorter and more numerous.

Microbodies: Microbodies include organelles like glyoxysomes and glycosomes, which are involved in lipid metabolism and carbohydrate metabolism, respectively.

88
Q

endomembrane system

A

complex and interconnected network of membrane-bound organelles within eukaryotic cells.

Protein Synthesis and Modification: The rough ER is involved in the synthesis of proteins, which are then modified and processed in the ER and Golgi apparatus before being transported to their final destinations.

Lipid Metabolism: The smooth ER is involved in lipid synthesis and metabolism, including the synthesis of membrane lipids and the detoxification of drugs and toxins.

Membrane Trafficking: Vesicles transport molecules between the various organelles of the endomembrane system and to and from the plasma membrane.

Waste Degradation: Lysosomes contain enzymes that break down cellular waste and cellular components that need to be recycled.

Endocytosis and Exocytosis: Endosomes are involved in the internalization of materials through endocytosis and the secretion of molecules through exocytosis.

89
Q

ribosomes

A

small, non-membranous organelles responsible for protein synthesis. They can be found attached to the rough ER or free in the cytoplasm.

90
Q

vesicles

A

Small, membrane-bound sacs that transport molecules between the various components of the endomembrane system. Vesicles can bud off from the ER, Golgi apparatus, or other organelles and fuse with other membranes to deliver their cargo.

91
Q

phagocytosis

A

a cellular process by which certain specialized cells, known as phagocytes, engulf and ingest solid particles or foreign material, such as bacteria, debris, and pathogens, for the purpose of destroying, digesting, or processing them.

92
Q

membrane structure

A

a feature in all cells, serving as a selective barrier that separates the cell’s internal environment from the external surroundings.

93
Q

mitosis

A

one cell divides into two genetically identical cells, all ploidy levels can do this

94
Q

meiosis

A

a diploid cell divides resulting in four distinct haploid cells with their genes
recombined

95
Q

Protists: Plankton

A

small organisms, can not swim against water movement, drifters.
* May be a juvenile stage in some organisms
* Basis of marine food chain.
* Phytoplankton – autotroph- photosynthetic
* Zooplankton – eat other plankton

96
Q

symbionts

A

organisms that engage in symbiosis, a biological interaction between two different species living in close physical proximity to each other.

97
Q

cysts

A

resistant cells formed in the cell life cycle

98
Q

Haploid (n)

A

one complete set of chromosomes – organisms can be haploid- like mosses

99
Q

Diploid

A

two complete sets of chromosomes

100
Q

Endosymbiotic theory for origin of Mitochondria and Chloroplasts

A

Origin of eukaryote cell structure
1) Archaea cell becomes proto-eukaryote by invagination of cell membrane forming the nucleus and endomembrane system

Origin of Mitochondria
2) Endosymbiosis- Mitochondria origin from proteobacteria ancestor.

Origin of Chloroplasts
3) Endosymbiosis Chloroplasts origin from cyanobacteria forming the Archaeplastida- Green and Red Algae.

Secondary endosymbiosis
4) Green and Red Algae (Eukaryotes) become chloroplasts in Euglena (Green algae) and in Diatoms, Brown algae, Dinoflagellates (Red algae) by secondary endosymbiosis

101
Q

xylem

A

carries water unidirectional flow soil→roots→stem→leaves→air

102
Q

phloem

A

carries sugar, flow is multidirectional throughout plant source→ sink

103
Q

Difference Between gamete and spore

A

gametes are specialized reproductive cells produced by multicellular organisms for sexual reproduction, while spores are reproductive cells produced by a variety of organisms, including plants and fungi.

104
Q

sporophyte

A

The sporophyte is the phase responsible for producing and dispersing spores, which ultimately develop into new gametophytes, and the cycle continues

105
Q

gametophyte

A

diploid zygote develops into the sporophyte, completing the alternation of generations life cycle.

106
Q

antheridia

A

found in mosses, liverworts, and hornworts, as well as some algae. They serve as the male reproductive organs responsible for producing and releasing sperm cells for fertilizing the egg cells produced by female reproductive structures known as archegonia

107
Q

archegonia

A

serve as the female reproductive organs responsible for producing and housing egg cells

108
Q

zygote

A

a eukaryotic cell that forms as a result of the fusion of two gametes during fertilization.

109
Q

sporangia

A

serve as the site for the production and release of spores.

110
Q

spores

A

serve as a means of reproduction and dispersal

111
Q

Photoautotrophs

A

organisms that can produce their own organic molecules, including sugars and other energy-rich compounds, using light energy from the sun

112
Q

Chemoautotrophs

A

organisms that can synthesize their own organic molecules, including sugars and other energy-rich compounds, using energy derived from chemical reactions involving inorganic substances.

113
Q

Chemoheterotrophs

A

organisms that obtain both their energy and carbon for growth and metabolism from organic compounds.

114
Q

Alfred Russel Wallace

A

British naturalist and biologist who independently formulated the theory of evolution by natural selection around the same time as Charles Darwin in the mid-19th century.