Learning intentions Flashcards
Eukaryote VS Prokaryote cells
eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. The nucleus is where eukaryotes store their genetic information.
Cellular Organelles (structure and function)
Organelles are small structures within the cytoplasm that carry out functions necessary to maintain homeostasis in the cell.
Genes and Alleles
Each variation of a gene is called an allele (pronounced ‘AL-eel’). These two copies of the gene contained in your chromosomes influence the way your cells work. The two alleles in a gene pair are inherited, one from each parent.
Theories of Natural Selection (Lamarck VS. Darwin)
Lamarck, who said that traits could develop and change during an animal’s lifetime. An example would be if a giraffe stretched its neck to reach for food it’s neck would grow. Darwin believed that individuals were simply born with different traits and that these differences were mostly random. An example would be if a Giraffe was born with a long neck it would have a higher chance of survival as it could reach for more food and pass that gene to future generations.
Variation
There must be variation within a population. Individuals in a population must exhibit differences in their traits (e.g., size, color, speed, etc.). These variations are often due to mutations, genetic recombination, and other genetic processes.
Inheritance
Traits must be heritable. The variations present in the population must be able to be passed down from one generation to the next. This means that offspring tend to resemble their parents more than unrelated individuals.
Differential Survival and Reproduction
There must be differential survival and reproduction. Because of their variations, some individuals are better suited to their environment than others. These individuals are more likely to survive and reproduce, passing on their advantageous traits to their offspring.
Overproduction:
More offspring are produced than can possibly survive. Organisms tend to produce more offspring than the environment can support, leading to competition for resources like food, shelter, and mates.
Transformation VS. Divergence
Transformation: Broad changes in traits or characteristics within a population, potentially leading to the emergence of a new species.
Divergence: Accumulation of genetic differences over time between populations, resulting in the formation of distinct species.
Allopatric Vs Sympatric
Allopatric Speciation:
Scenario: Populations geographically separated.
Mechanism: Physical barriers prevent gene flow.
Result: Accumulation of genetic differences, leading to distinct species.
Sympatric Speciation:
Scenario: Populations share the same geographic area.
Mechanism: Reproductive isolation without physical separation.
Result: Evolution of distinct species due to factors like ecological differences or specialized behaviors.
Immune System - The 3 lines of defense
These are three lines of defense, the first being outer barriers like skin, the second being non-specific immune cells like macrophages and dendritic cells, and the third line of defense being the specific immune system made of lymphocytes like B- and T-cells, which are activated mostly by dendritic cells
Viral structure (shared characteristics)
Viruses have several common characteristics: they are small, have DNA or RNA genomes, and are obligate intracellular parasites. The virus capsid functions to protect the nucleic acid from the environment, and some viruses surround their capsid with a membrane envelope
Lytic VS. Lysogenic pathways
In the lytic cycle, the phage replicates and lyses the host cell. In the lysogenic cycle, phage DNA is incorporated into the host genome, where it is passed on to subsequent generations.
Bacteria structure (prokaryotic characteristics)
much smaller than eukaryotic cells, have no nucleus, and lack organelles.
Phases of bacterial growth
the lag phase, the exponential or log phase, the stationary phase, and the death or decline phase.
