Gianelli - Biology 2025 Spring Semester Final Exam Study Guide

What do ALL female eggs cells have?

have one X chromosome

What is an unknown disease or a well-known disease that suddenly becomes harder to control called?

Emerging Disease

What are bacteria that cause disease?

Pathogens

What are bacteriophages?

Viruses that infect bacteria

How does the lytic cycle conclude?

Virus bursts out of the cell

Compared to small cells, large cells have more trouble with what?

Moving needed materials in and waste products out.

What advantage does sexual reproduction have over asexual reproduction?

Provides genetic diversity

During which phase in the cell cycle does mitosis happen?

M phase

Which pair includes a phase of the cell cycle and a cellular process that occurs during that phase?

G2 Phase, preparation for mitosis

When during the cell cycle is a cell's DNA replicated?

S phase

Which phases make up interphase of the cell cycle?

G1, S, G2

What is a centromere?

Point holding 2 chromatids together

What are the phases of mitosis?

Prophase, metaphase, anaphase, telophase

What is the first phase of mitosis?

Prophase

During which phase of mitosis do the chromosomes line up along the middle of the dividing cell?

metaphase

What is the proper sequence of mitosis?

prophase, metaphase, anaphase, telophase

What is the role of the spindle fibers during mitosis?

They help separate the chromosomes

What are the two main stages of cell division?

mitosis and cytokinesis

What is one difference between cell division in plant cells and in animal cells?

plants have a cell plate

What are cyclins?

Proteins that regulate the cell cycle

Cancer is a disorder in which some cells have lost the ability to control what?

Growth Rate

What are cancerous masses of cells called?

tumors

What are alleles?

Different forms of a gene

Why did Gregor Mendel remove the male parts from the flowers of some plants?

Prevent cross-pollination

What did the F1 plants inherit when Gregor Mendel crossed a tall plant with a short plant?

One allele from each parent

What is the probability of landing on tails when you flip a coin?

50%

What is the principle of probability used for?

predict the traits of the offspring of genetic crosses

What is the probability that an F1 plant will be tall when it's parents are heterozygous?

50%

What is homozygous?

two identical alleles for a specific trait

What principle states that during gamete formation genes for different traits separate without influencing each other's

inheritance?

Independent Assortment

Who does Gregor Mendel's principle of genetics apply to?

all organisms

What is incomplete dominance?

One allele for a gene is not completely dominant over another allele

What is an example of a polygenic trait?

Variation is skin color

What helps to influence changes in an organisms physical appearance?

Genes and Environment

What letter represents the number of chromosomes in a gamete?

N

If haploid is one set of chromosomes, what is diploid?

2 sets of chromosomes

How many alleles do gametes have?

one allele for each gene

How are gametes produced? (what process)

Meiosis

Which cells are haploid?

gametes

Which structures assort independently?

Chromosomes

What chromosomes make a human male?

X and Y

What effect do most mutations have?

None

What is the only chromosome found in an egg cell?

X

What percentage of human sperm cells carry an X chromosome?

50%

How many chromosomes are shown in a normal human karyotype?

46

Where are sex-linked genes found?

On the X and Y chromosomes

What happens when a chromosome undergoes a deletion mutation?

Information is lost

What is a point mutation?

Mutation involving one or a few nucleotides

Where does transcription and translation take place?

Nucleus (transcription) and Cytoplasm (translation)

What is the correct sequence of the transfer of information in most organisms?

DNA to RNA to Protein

What do genes contain?

Instructions for assembling proteins

When is a protein assembled?

when RNA is translated

What happens during translation?

The cell uses a messenger RNA code to make proteins

There are 64 codons and 20 amino acids. Why is that?

Several different codons can specify the same amino acid.

How many nucleotides are needed to specify three amino acids?

9

What is produced during transcription?

RNA molecules

From which molecules are mRNA molecules transcribed?

mRNA molecules transcribed from DNA

Which molecules are involved in protein synthesis?

messenger RNA, ribosomal RNA, and transfer RNA

Which type of RNA brings the information in the genetic code from the nucleus to other parts of the cell?

mRNA

Describe DNA.

Double helix, sugar is deoxyribose, phosphate group, 4 bases-A, T, G, C

Describe RNA

Single helix, sugar is ribose, phosphate group, 4 bases-A, U, G, C

When does DNA replication happen?

Before cell division

Where is DNA located in eukaryotes?

Nucleus

During DNA replication, a DNA strand that has the bases CTAGGT produces a strand with these bases

GATCCA

What did Watson and Crick discovered about the two strands in DNA?

DNA run in opposite directions.

Which scientist made x-ray diffraction photos of DNA?

Franklin

Which scientist(s) figured out that the shape of a DNA molecule is a double helix?

Watson and Crick

What structural problem prevents adenine from pairing with guanine?

The bases are both long

In which cells is the accurate transmission of information most important?

Sex cells

In what way is DNA like a book?

DNA has stored information, that can be copied and passed on

What happens when a piece of DNA is missing?

Genetic information is lost

What stores information in a cell?

DNA

What do bacteriophages infect?

Bacteria

What is inside a bacteriophage?

Nucleic Acid

What happened when Griffith injected mice with the harmless, R-strain bacteria alone?

The mice lived

What did Avery conclude caused transformation?

DNA was the transforming factor

Why did Griffith call the process he observed transformation?

because the harmless bacteria had been transformed.

What part of the cell assort independently?

chromosomes

What is the basic structure of a virus?

DNA or RNA surrounded by a protein coat

What characteristic of living things is NOT true about viruses?

Unable to obtain or use energy

Where are the instructions for making new copies of virus found?

DNA or RNA

What three materials make up many viruses?

proteins, nucleic acids, and lipids

What is the outer protein coat of a virus called?

capsid

What is conjugation?

the exchange of genetic material by prokaryotes

What are prokaryotes that break down dead organisms and wastes called?

Decomposers

What three characteristics are used to classify prokaryotes?

by shape, how they move, and how they get energy

What are endospores?

Protection developed by bacteria to help it survive in unfavorable conditions

How do Bacteria and Archaea differ?

Make-up of their cell walls

The three-domain system recognizes fundamental differences between two groups of what?

Prokaryotes

Why did the three-domain system arise?

Scientists found that Eubacteria and Archaebacteria were very different

Which chromosome forms a Barr body?

one of the X chromosomes in a female cell

What does the formation of a Barr body do?

inactivates one whole X chromosome in a female cell

A cat that has spots of more than one color is what sex?

usually female

In cystic fibrosis, a change in a single gene causes the protein called CFTR to do what?

fold improperly

Compared with normal hemoglobin, the hemoglobin of a person with sickle cell disease is?

less soluble

Which disease does not appear until late in a person's life?

Huntington's Disease

Why are people who are heterozygous for sickle cell disease generally healthy?

because they have some normal hemoglobin in their red blood cells

What is the failure of chromosomes to separate called?

nondisjunction

Which chromosome combination represents a female?

XX

All babies must have which sex chromosome?

X