ACT Science (copy)

What is an allele?

One of two or more versions of a gene, which can be dominant or recessive.

How are recessive alleles represented?

Recessive alleles are represented by a lowercase letter, such as 'b'.

What is a genotype?

The combination of alleles that an individual possesses for a certain trait.

What does phenotype refer to?

The physical, observable traits of an organism, such as eye color.

What is a recessive trait?

A trait that requires two matching recessive alleles to be expressed.

What is the definition of a dominant trait?

A trait that only requires one dominant allele to be expressed.

What does heterozygous mean?

When an organism has two different alleles for a certain trait.

What does homozygous mean?

When an organism has two identical alleles for a certain trait.

What is a chromatid?

A strand of DNA.

What is a chromosome?

A cluster/segment of DNA that contains two chromatids bound together.

Define gametes.

Reproductive cells specific to each gender (sperm and egg) that carry half of the parent's alleles.

What are nucleic acids?

Carriers of genetic information, including DNA and RNA.

What are nucleotides made of?

A nitrogenous base, a 5-carbon sugar, and a phosphate group.

What are purines?

A class of nucleotides that includes adenine and guanine.

What are pyrimidines?

A class of nucleotides that includes cytosine, thymine, and uracil.

What does the nucleus do in a cell?

It acts as the 'brain' of a cell, containing its DNA.

What is the main function of mitochondria?

It creates energy in the form of ATP.

What does ATP stand for?

Adenosine Triphosphate, a molecule that stores energy for the cell.

Describe cellular respiration.

The process by which glucose and oxygen are converted into carbon dioxide and water to create energy.

What is photosynthesis?

The process by which plants convert carbon dioxide, water, and sunlight into glucose and oxygen.

What is the role of chlorophyll?

A green pigment used in photosynthesis.

What is glucose?

A simple sugar produced by plants during photosynthesis.

Define osmosis.

The movement of solvent molecules through a membrane to equalize solute concentrations.

What constitutes aerobic processes?

Processes that require oxygen.

What characterizes anaerobic processes?

Processes that do not require oxygen.

What are carbohydrates?

Compounds that include sugars and starches, serving as common energy sources for animals.

What are proteins made of?

Amino acids, which are the building blocks of cells.

Define lipids.

Compounds including fats and oils that are insoluble in water and store energy.

What are amino acids?

The building blocks of proteins.

Define hormones.

Chemical messengers that regulate bodily functions.

What is fermentation?

An anaerobic process that breaks down glucose into carbon dioxide and alcohol or lactic acid.

What is an endotherm?

A warm-blooded organism.

What is an ectotherm?

A cold-blooded organism.

Define symbiotic relationships.

Relationships between species that benefit one or more of the organisms involved.

What are the taxonomic ranks?

Groups that classify organisms: Kingdom, Phylum, Class, Order, Family, Genus, Species.

What are decomposers?

Organisms that consume decaying or dead material.

What is binomial nomenclature?

A naming system for living things that consists of the genus name and species name.

Define igneous rock.

Rock formed from cooled magma and/or lava.

What is sedimentary rock?

Rock formed from the collection of small particles such as sand.

What defines metamorphic rock?

Rock formed when subjected to heat and/or pressure.

What is run-off in environmental science?

The process by which rainwater slides off land into lakes and rivers.

What are Earth's layers?

Crust, mantle, outer core, inner core.

What are greenhouse gases?

Gases that trap infrared radiation and increase Earth's temperature.

What is an autotroph?

An organism that can produce its own food from sunlight and other chemicals.

What is a heterotroph?

An organism that eats other organisms.

Who are primary consumers?

Organisms that eat autotrophs, like grasshoppers.

What are secondary consumers?

Organisms that eat primary consumers, such as birds and snakes.

What are tertiary consumers?

Organisms that eat secondary consumers, like wolves and lions.