Third Quarter Science Vocabulary - Sixth Grade - Mr. Benton

chromosome- a structure in a cell's nucleus that is made of DNA and which transfers hereditary information to the next generation

 

gene - matching sections (alleles) of a pair of chromosomes that carry a chemical code for features of organisms 

 

ratio - a comparison of two numbers, for example, if there are 3 striped larkeys and 1 spotted larkey, the ratio is 3:1

 

dominant, recessive -  in genetics, dominant refers to the form of a gene that is expressed or shows up whenever it is present and recessive is the form of the gene that doesn't show up unless there is no dominant gene present 

 

genotype, phenotype - 'genotype' refers to the letters that represent the genes of a trait of an organism, for example:  TT is the genotype for tall pea plants.  'Phenotype' means the actual trait that is expressed, for example: 'tall' is a phenotype in pea plants

 

Punnett square -  a diagram which shows the possible offspring genotypes when two particular parents breed

 

heterozygous gene, homozygous gene - heterozygous genes have two different alleles, one dominant and one recessive, for example: Tt, Aa, Ff; homozygous genes have two identical alleles, for example, both dominant or both recessive: TT, aa, FF, ff

 

 

 

heredity - the passing on of traits from one generation to the next

 

partial dominance - type of inherited characteristic in which a heterozygous gene  results in a trait unlike the dominant trait or the recessive trait, for example the larkey fur

allele - a section of one chromosome that codes for a trait and corresponds to an allele on the other chromosome of the homologous pair.  The two alleles that code for the same feature on a homologous pair of chromosomes make up a gene. 

pattern:  Ff (heterozygous) results in solid patterned fur rather than striped (dominant) or spotted (recessive).

 

homologous pair - two "matching" chromosomes, one originally from the male parent, one originally from the female parent, which code for the same features but which may have differences (dominant or recessive)

 

selective breeding - humans choosing to breed organisms for their beneficial characteristics

 

natural selection - process that allows well-adapted organisms to survive and reproduce

 

genome - the complete set of genes of an organism. The human genome project has cataloged 30000 human genes.

 

mitosis / meiosis-  two types of cell division (reproduction).  Mitosis occurs in all body cells and results in two complete duplicate cells

 

responding variable – The changes or results that are observed and measured.  All experiments must have one responding variable.

 

manipulated variable – The variable I chose to change during the experiment.  All experiments must have one manipulated variable.

 

constant variables – all variables that are kept the same during the experiment.  Experiments usually have many controlled variables.

 

system – made up of parts that work together for the benefit of the whole.  A group of organs that work together to perform a specific function. 

 

organ – a group of different tissues working together to perform a specific function.

 

mucus – a slippery secretion that coats the inner walls of the digestive tract.  It helps food slide down and is also a form of protection.

 

sphincter – a ring of muscles at the beginning and end of the digestive tract.  Sphincters are located in between organs

 and make sure that food only goes in a one-way direction.

 

peristalsis – the wave-like motion of the digestive tract that moves food through.

 

mechanical digestion - the breaking apart of food by the action of teeth, tongue and muscles of the digestive tract

 

chemical digestion - the breaking down of food particles by the action of acids and enzymes in the digestive tract

 

 

 

 

 

 

 

 

 

 

 

partial dominance - type of inherited characteristic in which a heterozygous gene  results in a trait unlike the dominant trait or the recessive trait, for example the larkey fur pattern:  Ff (heterozygous) results in solid patterned fur rather than striped (dominant) or spotted (recessive).

 Punnett square - a diagram used to show the possible ratios of offspring resulting from a particular combination of alleles

homologous pair - two "matching" chromosomes, one from the male parent, one from the female parent, which code for the same features but which may have differences (dominant or recessive)

  mitosis, meiosis -  two types of cell division (reproduction).  Mitosis occurs in all body cells and results in two complete duplicate cells

  base pairs - chemicals which make up the "rungs" in the double helix ladder of DNA. 

  genome - the complete set of genes of an organism.  The human genome project has cataloged 30000 human genes.

 endemic - describes an organism whose habitat is restricted to one location

 natural selection - process that allows well-adapted organisms to survive and reproduce

 selective breeding - humans choosing to breed organisms for their beneficial characteristics

 protein - chemical building blocks in the body which are synthesized (put together) by DNA

extinction - complete disappearance of a species

 selective pressure - something in the environment that allows some members of a species to be more successful than others at surviving and reproducing, because of the variations in those members of the species (adaptations)

 protein - chemical building blocks in the body which are synthesized (put together) by DNA

evolution - change over time as a result of variations within a species, that can result in new species as a result of natural selection

global warming - a rise in the average temperature in the Earth's atmosphere, which may be caused by rising levels of carbon dioxide in the atmosphere

leaching - rain falling on toxic materials and picking up polluting materials and washing them into the soil

 landfill - an area used to dispose of solid waste in the ground; a garbage dump

 acid rain -  a mixture of sulfur and nitrogen from car and factory exhaust that combines with water vapor in the atmosphere

 aquifer - an underground layer of porous rock and soil that holds a lot of water.  It is like an underground sponge

 toxic - poisonous  ("toxin" is a poison)

biodegradable - able to be decomposed or broken down into simpler forms by the action of living organisms;  a ham sandwich is biodegradable, but the plastic bag the sandwich came in is not biodegradable

greenhouse effect -  the trapping of heat energy in the atmosphere by gases like carbon dioxide; similar to  a greenhouse trapping the heat of the sun inside the glass walls of the greenhouse

reclamation - restoring land and natural resources to the same condition as they enjoyed before mining or forestry destroyed some of the natural setting

source reduction - keeping the amount of garbage lower by not creating so much in the first place, by using less packaging, buying fewer products and recycling recyclable materials

irrigation - artificial watering of plants, yards, farms, etc.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

heterozygous gene, homozygous gene - heterozygous genes have two different alleles, one dominant and one recessive, for example: Tt, Aa, Ff; homozygous genes have two identical alleles, for example, both dominant or both recessive: TT, aa, FF, ff.

 

 

 

 

 

 

 

 

individual - a single organism of any species

  population - all the members of one species in one place at one time

 

  community - interacting populations of more than one species

 

   ecosystem - communities of organisms interacting with each other and the abiotic parts of their environment

 

biotic/ abiotic -  scientific terms for living and non-living

 

carbon dioxide - a gas which makes up less than 4% of our atmosphere, but is necessary for photosynthesis;  chemical symbol:  CO2

 

 global warming - a rise in the average temperature in the Earth's atmosphere, which may be caused by rising levels of carbon dioxide in the atmosphere

 

  habitat - the supportive environment where an organism is adapted to live

  

autotroph/  heterotroph - an autotroph is an organism which makes its own food (like a plant);  a heterotroph is an organism that must eat other organisms for its energy needs

energy - the ability to do work; comes in many forms - chemical energy, heat energy, electrical energy, etc.

trophic level:  the position of an organism in an ecosystem related to its feeding habits; e.g.: producer, primary consumer, secondary consumer, etc. 

 producer/consumer - other terms for autotrophs and heterotrophs;  organisms that make food from sunlight, and organisms that eat other organisms

organic  - relating to living things, or things that used to be alive, or things that came from living things

  food web - a diagram showing the energy flow through an ecosystem's populations

"10% rule" - on average, only 10% of energy and matter consumed by an organism at a lower trophic level is passed on to the next higher consumer level because most energy is used by any given organism to perform life processes.

proboscis - tube shaped mouth of "true bugs"  like a milkweed bug     

instar - a nymphal stage in incomplete metamorphosis

reproductive potential - the number of offspring that an individual might possibly give birth to 

  limiting factor - any influence which reduces the reproductive capacity of a population

carrying capacity- the ability of an ecosystem to sustain (keep alive) a certain number of individuals

  algae - usually single-celled, photosynthesizing protists that form the base of aquatic food webs, such as in Mono Lake

larvae - the worm-like stage of organisms going through complete metamorphosis 

migratory - describes animals like some birds which travel great distances to avoid the limiting factor of winter, or to find suitable reproductive environments 

predator - an organism that hunts and kills other organisms for food

 detritivore - an organism like a worm or beetle that eats dead material (detritus) but doesn't break the material down into its simplest form (and is therefore not referred to as a decomposer in our book)

  calorie - the amount of heat energy needed to raise the temperature of one milliliter of water one degree Celsius   

 carbohydrate - a sugar or starch; the source of energy in many foods; chemical formula contains carbon, hydrogen and oxygen

  feature - a structure, characteristic or behavior of an organism, such as eye color, fur pattern, or timing of migration, which helps to identify the organism

 trait - the specific way a feature is expressed in an individual:  eye color is a feature; blue eyes are a trait

  variation - the range of differences in a trait in any population;  for example, there is a variation in the color of walking sticks:  brown, green-brown and green.

 

 DNA - deoxyribonucleic acid; the complex chemical that forms chromosomes and carries genetic information to the next generation 

appendage - a leg or an arm or a flipper

partial dominance - type of inherited characteristic in which a heterozygous gene  results in a trait unlike the dominant trait or the recessive trait, for example the larkey fur pattern:  Ff (heterozygous) results in solid patterned fur rather than striped (dominant) or spotted (recessive).

 Punnett square - a diagram used to show the possible ratios of offspring resulting from a particular combination of alleles 

homologous pair - two "matching" chromosomes, one from the male parent, one from the female parent, which code for the same features but which may have differences (dominant or recessive)

  mitosis, meiosis -  two types of cell division (reproduction).  Mitosis occurs in all body cells and results in two complete duplicate cells 

  base pairs - chemicals which make up the "rungs" in the double helix ladder of DNA.  

  genome - the complete set of genes of an organism.  The human genome project has cataloged 30000 human genes. 

 endemic - describes an organism whose habitat is restricted to one location

 natural selection - process that allows well-adapted organisms to survive and reproduce

 selective breeding - humans choosing to breed organisms for their beneficial characteristics

 protein - chemical building blocks in the body which are synthesized (put together) by DNA

extinction - complete disappearance of a species