Life Science Flashcards
Things that have physical entities and biological processes (such as homeostasis, cell division, cellular respiration, and photosynthesis)
Living things/animate
Things that do not have biological processes
Nonliving things/inanimate
What are the three components of Cell Theory?
1) All living things are composed of cells
2) The cell is the smallest unit of life
3) All cells come from pre-existing cells
Describe the organization of life (in order of smallest to largest)
Cells < Tissues < Organs < Organ Systems < Organisms
A unicellular organism that lacks a nucleus, mitochondria, or any other membrane-bound organelle. DNA floats freely throughout the cell.
Prokaryote
A multicellular organism that contains a nucleus, mitochondria, and membrane-bound organelles.
Eukaryote
What are the two domains of prokaryotes?
Archaea and Bacteria
Structures within the cell membrane or cell wall
Organelles
Fluid, permeable outside covering of the cell. Called a cell wall in plant cells, and it is rigis.
Cellular Membrane
Controls the rest of the cell. This is where the DNA lives in eukaryotic cells.
Nucleus
Energy source of the cell; they use aerobic respiration to generate ADP, which is used throughout the cell as a source of chemical energy.
Mitochondria
the gelatinous liquid that fills the inside of a cell. It is composed of water, salts, and various organic molecules.
Cytoplasm
What are the main differences between plant and animal cells?
1) Plant cells have a cell wall, which provides structure and support, while animal cells have a plasma membrane.
2) Plant cells contain chloroplasts, which are responsible for photosynthesis, while animal cells do not.
3) Plant cells have a larger central vacuole, which stores nutrients and waste, while animal cells have smaller, more numerous vacuoles.
4) Plant cells are autotrophs (make their own food) and do so through photosynthesis. Animal cells are heterotrophs and need to consume food which they will use to create ATP/energy through cellular respiration.
Photosynthesis formula
CO2 + H20 + light = carbohydrates + O2
Cellular respiration formula
Carbohydrates + O2 = CO2 and H20
Form of reproduction that involves two parents, where each parent contributes a gamete to the process.
Sexual reproduction
Sex cells (in males = sperm, in females = ova)
gametes
Involves only one parent. There are four main types.
Asexual reproduction
When a single parent cell doubles its DNA, then divides into two cells. Usually occurs in bacteria.
Binary fission
When a small growth on the surface of a parent cell breaks off to continue growing into adulthood. Typically occurs in yeast and some animals (like corals and hydras).
Budding
When a piece of an organism breaks off, and those pieces develop into a new organism. Happens with starfish and planaria.
Fragmentation
When an embryo develops from an unfertilized cell. This occurs in invertebrates as well as in some fish, amphibians, and reptiles.
Parthenogenesis
Type of cell division- is a series of steps in creating an identical cell from another cell
Mitosis
Stage where the cell prepares for division. It plumps up and replicates its DNA within its nucleus.
Interphase
Stage of cellular replication where the DNA tightly coils into chromosomes to make splitting efficient. The nuclear membrane dissolves. The microtubes or spindle fibers move to opposite sides of the cell.
Prophase
Stage of cellular replication where the chromosomes (tightly coiled DNA) move to the middle of the cell. The spindle fibers attach to each chromosome.
Metaphase
Stage of cellular replication where the spindle fibers begin to pull apart the chromosomes, bringing them to opposite sides of the cell for efficient splitting.
Anaphase
Stage of cellular replication where, with the chromosomes at either side of the cell, the two new cells pinch off, forming two identical sister cells of the original cells.
Telophase
When the cell separates into two cells during the final stage of mitosis.
Cytokinesis
Type of cell division that ensures humans have the same number of chromosomes in each generation. It is a two-step process that reduces the chromosome number by half to form sperm and egg cells.
Meiosis
How many chromosomes are in a cell? How many pairs?
each cell in the human body has 23 pairs of chromosomes (46 total chromosomes)
(‘three bodies’) means the affected person has three copies of one of the chromosomes instead of two. This means they have 47 chromosomes instead of 46.
Trisomy
Humans usually have 46 total chromosomes, with ___ sex chromosomes that determine sex and ___ chromosomes that direct other factors, such as growth and function.
2; 44
The molecule inside cells that contains the genetic information responsible for the development and function of an organism.
DNA
The four nitrogen bases
Adenine, Thymine, Guanine, and Cytosine
joins together nucleotides in a DNA sequence; it forms the structural framework of nucleic acids, including DNA and RNA. It is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.
Sugar phosphate backbone
__ pair with Ts
__ pair with Gs
As; Cs
Organic compounds that form proteins. Coded for by the four nitrogen bases on the DNA. Chains of these make proteins.
Amino Acids
Give a summary of the process of DNA replication (3 steps)
1) The DNA unzips
2) Free-flowing nucleotides bind to their corresponding base pairs
3) Two identical DNA strands are the result
The basic physical and functional unit of heredity. These are made up of DNA and they act as instructions to make molecules called proteins.
Genes
Each person has ___ copies of each gene
Two (one inherited from each parent)
Forms of the same gene with slight differences in their sequence of DNA bases
Alleles
When the effect of one phenotype of one allele masks the contribution of a second allele at the same locus
Dominance
Known as the Father of Genetics for his work with pea plants in the 19th century. Coined the terms recessive and dominant.
Gregor Mendel
The process of transformation from an immature form to an adult form in two or more distinct stages
Metamorphosis
Type of metamorphosis in insects that consists of four stages: egg, larva, pupa, imago
Complete metamorphosis
Type of metamorphosis in insects that consists of three stages: egg, nymph, and adult. The pupa stage is not developed.
Incomplete metamorphosis
the change in heritable characteristics of biological populations over successive generations
evolution
T or F: organisms evolve
F; organisms do not evolve, only populations
a heritable trait that has evolved through the process of natural selection, and maintains or increases the fitness of an organism under a given set of environmental conditions
Adaptation
a change in the DNA sequence of an organism. Can result from errors in DNA replication during cell division, exposure to mutagens or a viral infection.
Mutations
animals that are not capable of regulating their body’s temperature according to the temperature of the surrounding
cold-blooded animals
animals that are capable of maintaining a nearly constant body temperature regardless of the temperature of the environment (for example by sweating/shivering)
warm-blooded animals
Type of circulatory system where the blood is pumped into the body cavity and is not enclosed in blood vessels (found in most invertebrates)
Open circulatory system
Type of circulatory system where the blood is pumped by the heart and is enclosed in blood vessels (found in most vertebrates)
Closed circulatory system
Human system responsible for the flow of blood, nutrients, oxygen and other gases, and hormones to and from cells
Circulatory & Respiratory System
Human system responsible for taking in food and breaking it up into nutrients the body will use for fuel. It is also responsible for removing the waste left over after the food is processed.
Digestive & Excretory System
Human system that serves as the “master control system” - oversees function of the brain, spinal cord, neurons, and hormones
Nervous, Endocrine & Immune System
Person who created the Classification of Living Things, set forth in his Systema Naturae
Carl Linnaeus
Go through the Taxonomy of Linnaeus, in order from largest to smallest
Domain > Kingdom > Phylum > Class > Order > Family > Genus > Species
What are the three domains? (classification)
Archaea, Eubacteria, Eukaryote
What are the six Kingdoms?
Eubacteria, Archae, Protista, Fungi, Plantae, and Animalia
What are the “functional levels” that make up life?
species, populations, communities, and ecosystems
A group of interbreeding organisms that do not ordinarily breed with members of other groups
Species
Comprises all the individuals of a given species in a specific area or region at a certain time. These groups can evolve over time because of genetic variation.
Populations
All the populations in a specific area or region at a certain time. There are many interactions among species in these groups (i.e., food webs).
Communities
group of organisms linked in order of the food they eat, from producers to consumers, and from prey, predators, scavengers, and decomposers (basically: who eats who)
Food chain
consists of all the food chains in a single ecosystem
Food web
The dynamic entities composed of the biological (living) community and the abiotic (nonliving) environment
Ecosystems
these organisms produce their own food from sunlight, co2, and water. Usually at the bottom tier of the food chain.
Producers
These organisms eat their food (they do not produce it)
Consumers
Herbivores (type of consumer)
Primary consumer
eat the primary consumer (type of consumer)
Secondary consumer
eat the secondary consumers and are usually carnivores (type of consumer)
Tertiary consumer
eat the tertiary consumers and are carnivores (type of consumer); also known as apex predator
Quaternary consumers
These organisms turn dead material, such as an animal carcass or a dead tree, into soil by recycling nutrients as food
Decomposers
As you move up the energy pyramid, what happens to energy?
It is reduced
The interaction among organisms within or between overlapping niches; can be characterized into five types
Ecological relationships
When two or more organisms rely on the same environmental resource
Competition
Behavior of one animal feeding on another
Predation
Interaction between two different organisms living in close physical association
Symbiosis
A symbiotic relationship where both organisms benefit
Mutualism
A symbiotic relationship where one organism benefits and one does not benefit but is unharmed
Commensalism
A symbiotic relationship where one organism benefits and one is harmed
Parasitism
The maximum population of a particular organism that a given environment can support without detrimental effects
Carrying capacity
