Genetics - 8 East

What would a homozygous dominant, homozygous recessive, and heterozygous genotype look like?

A homozygous dominant genotype would contain two dominant alleles. A homozygous recessive genotype would contain two recessive alleles. A heterozygous genotype would contain one dominant and one recessive allele.

How do nucleotides pair up?

A nucleotide with a adenine base always pairs up with a nucleotide with a thymine base. A nucleotide with a cytosine base always pairs up with a nucleotide with a guanine base.

What are the differences and similarities between asexual reproduction and sexual reproduction?

Asexual reproduction is different from sexual reproduction because asexual reproduction is the production of offspring that is genetically identical to the parent while sexual reproduction creates organisms that share half of the genetics of both parents. Similarities between asexual reproduction and sexual reproduction are that they both create offspring.

When are copies of DNA made?

Copies of DNA are made before a cell divides so that each new daughter cell will have a complete set of instructions.

What are three drawbacks to artificial selection?

Three drawbacks to artificial selection is that it takes a long time to create a new breed of an organism, only organisms of the same species can be crossed, crossing closely related organisms may also pass on undesirable traits.

How can artificial selection be used to create desirable traits in plants and animals?

You can breed two plants or animals of the same species with a desired trait which will eventually create an offspring with that desired trait.

How do you determine the probability of an offspring inheriting specific traits using a Punnett Square?

You can determine the probability of an offspring having a specific trait using Punnett Squares by creating different combinations of both parent's alleles. Then you would find the probability of that trait being chosen from all the other traits.

How can you know a phenotype based on the genotype?

You can tell a phenotype based on the genotype by looking at the alleles of the chromosome. If at least one chromosome of the pair has a dominant allele the phenotype will be determined by that dominant allele. If both chromosomes of the pair have recessive alleles than the phenotype will be determined by the recessive allele.

What does each chromosome contain?

Chromosomes contain the area where genes are located.

What does DNA code for?

DNA codes for which proteins the cells should build.

What are examples of asexual reproduction?

Examples of asexual reproduction are binary fission, budding, spores, and vegetative reproduction.

How is meiosis involved in sexual reproduction?

Sexual reproduction is when two parents contribute a sex cell to a new organism. Meiosis is a cell division that creates sex cells.

What is an example of many genes influencing a single trait?

The color of your hair, skin, and eyes are the result of many genes acting together. Different combinations of alleles can result in different shades of eye color.

How do cells go from DNA to proteins?

The information from the DNA is copied to a separate molecule called RNA. The RNA runs through a cell organelle called a ribosome. The RNA molecule transfers amino acids to the ribosome that join together to form a protein.

Which pairs of sex chromosomes determine each biological sex?

The pair of X chromosomes determines a female and one X and one Y chromosome determines a male.

What is the purpose of proteins in our body?

The types of proteins in your body determines your traits.

What is the difference between an allele, a phenotype, and a genotype?

Alleles are the different versions of a gene, a phenotype is your observable traits, and your genotype is the combination of alleles inherited from your parents.

What are the advantages and disadvantages of asexual and sexual reproduction?

An advantage of sexual reproduction is that the offspring have more genetic variety meaning they can survive if the climate changes. An advantage to asexual reproduction is that the production of offspring is faster, greater, and only requires one parent organism. A disadvantage to sexual reproduction is that it is more complicated, produces less offspring than asexual reproduction, and requires two parent organisms. A disadvantage to asexual reproduction is that its offspring have no genetic variety and can not survive when their ecosystem changes.

What is an example of a single gene influencing many traits?

An example of a single gene influencing many traits is a gene that affects fur and eye color of some tigers.

What is an example of the environment influencing traits?

An example of the environment influencing traits is how the number of hours of light there is in a day affect the arctic fox's coat color. With less light, the coat grows white. With more light, the coat grows brown.

How can DNA change?

Changes in the DNA are called mutations. Mutations can change the number, type, or order of bases on a piece of DNA.

Why are chromosomes in pairs?

Chromosomes are in pairs because they come from each of two parents.

What are DNA molecules made up of?

DNA molecules are made up of nucleotides. Nucleotides are made up of a base, (adenine, thymine, cytosine, and guanine), a sugar, and a phosphate.

What are some example of mutagens?

Mutagens are chemical or physical agents that can damage the DNA. Examples are ultraviolet light and cigarette smoke.

How can some mutations be harmful, helpful, or neutral?

Some mutations can change an organism's skin color which doesn't help or harm the organism. Cancer is a mutation of the DNA that harms the organism and can kill them. Being lactose tolerant is a mutation in people that helps the person and allows them to digest milk.

What is the shape of a DNA molecule?

The shape of a DNA molecule is a double helix.

How many total pairs of chromosomes do humans have?

Humans have 23 pairs of chromosomes.

What are example of organisms that have changed over time due to people performing artificial selection?

Wolves have been bred over time by people through artificial selection and eventually turned into the modern dog.