Biology: Unit 3 Exam Review

The probability of obtaining a dominant phenotype from self fertilization of a heterozygous individual is

75%

A male is heterozygous for the trait that produces freckles on the skin, and he has freckles. If he marries a woman who is also heterozygous for freckles, _____ percent of their children are predicted to be freckled. Also, of all their children, _____ percent are predicted to be heterozygous.

75%, 50%

endergonic

A chemical reaction that requires the input of energy in order to proceed.

catabolic

A process in which large molecules are broken down

anabolic

A process in which large molecules are built from small molecules

What are the final by products of glucose oxidation during aerobic cell respiration?

ATP, heat and carbon dioxide

Examples of mendelian phenotypes

Albinism (recessive) Achondroplasia. Alkaptonuria. Ataxia telangiectasia. Brachydactyly (shortness of fingers and toes) Colour blindness (monochromatism, dichromatism, anomalous trichromatism, tritanopia, deuteranopia, protanopia) Cystic fibrosis. Duchenne muscular dystrophy.

Which relationship about nucleotide composition in DNA is correct?

C+A = G + T

Meiosis

Cell division that produces reproductive cells in sexually reproducing organisms

T or F: A strand of DNA is composed of nucleotide bases, sulfate groups, and sugars

False

T or F: If there is 28% adenine, then there must be 28% cytosine for the DNA composition of a particular organism

False

When grouping organisms, which classification is most general for a particular type of organism?

Kingdom

Eyelash length is an inherited trait. In the human population, there is an eyelash length gene. There are two possible variants of this gene - an allele for long eyelashes (> 1cm) and an allele for short eyelashes (1 cm or less). An individual who is heterozygous for eyelash length would have which of the following genotypes?

LI

Why must the life cycle of sexuality producing species alternate between haploid and diploid stages?

Meiosis must occur at some point in the life cycle to prevent a doubling of chromosomes in each generation

The process by which haploid cells are produced from diploid cells is called

meiosis

Carbon and hydrogen have similar electronegative and combine together to form hydrocarbon molecules. What type of bonds from between these atoms?

nonpolar covalent

The nucleus is to eukaryotes as the ________ is to prokaryotes.

nucleoid

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

The nucleotides within DNA are composed of a

phosphate group, deoxyribose sugar, nitrogenous base

When forming a list to describe the structures and organization of the nucleus, the main areas you would want to include are ________

pores mRNA tRNA chamois

In the blood clotting process, platelets arrive at the site of damage and start secreting substance to attract more platelets. More platelets arrive at the site and secrete attractants to recruit more platelets. This is an example of

positive feedback

Large numbers of ribosomes are present in eukaryotes cells that product

proteins

During glycolysis, glucose is broken down into

pyruvate

A substrate binding to an enzyme is most similar to a signal molecule binding to a

receptor

In a catabolic reaction, electrons from food are

removed by oxidation and stored in NADH

Sodium concentrations are higher outside and glucose concentrations are higher inside the cell. Using the same membrane proteins for Na+ and glucose transport, what is it called when a Na+ electrochemcal gradient is used to drive glucose transport into the cell against its concentration gradient?

secondary active transport

The gonands produce steroids. The specific steroid-producing organelles in gonad cella are

smooth ER

What serves are the ''translator'' or intermediary between an mRNA condon and an amino acid?

tRNA

T or F: The capacity to maintain a fairly constant body temperate is a homeostatic process

true

T or F: Whether a signaling molecule operates locally or over long distances, it must bind to a specific receptor to elicit a cellular response

true

T or F: when table salts dissolves in water, the salt is called the solute

true

What is a dominant allele?

an allele that is fully expressed in the phenotype of a heterozygote

Sister chromatids separate during

anaphase of meiosis II

A cell secretes is growth factor that binds to receptor on its own membrane preventing it from proliferating. This is an example of

autocrine signaling

Which of the following statements about the cell cycle is correct? a) the phases of the cell cycle are G1, S and M phases b) During G2 phase, the cell grows that cities its chromosomes in preparation for cell division c) the cell cycle is a sequence of replications and divisions that produces numerous new cells d) When the S phase of the cell cycle is finished, a cel has twice as much DNA as it did during the G1 phase e) In actively dividing cells, the S and G2 phases are collectively known interphase

b)

Which of the following statements is FALSE concerning sister chromatids? a) sister chromatids are held together at the centromere by cohesion proteins b) sister chromatids separate during anaphase I of meiosis c) the formation of sister chromatids doubles the amount of DNA in a cell d) sister chromatids consist of two identical copies of a single homologue e) sister chromatids are formed during the S phase of the cell cycle

b)

If the tight junctions in the intestine were disrupted

bacteria could move from the intestines to the bloodstream causing an infection

Differentiate the types of genetic mutations

base substitutions: involve the swapping of one nucleotide for another during DNA replication. deletions: type of mutation that involves the loss of one or more nucleotides from a segment of DNA. insertions: type of mutation that involves the addition of one or more nucleotides into a segment of DNA.

What would result from a single nucleotide deletion (point mutation) within the coding sequence of a structural gene? a) a silent point mutation with no defects b) all choices are correct c) a frameshift mutation, producing a completely different amino acid sequence

c)

Which is NOT a critical factor for DNA replication of the leading strand? a) DNA primase b) DNA polymerase c) DNA ligase d) Deoxynucleoside triphosphates e) primer

c)

The process through which cells can detect and respond to signals in their extracellular environment is called

cell communication

Where does glycolysis take place?

cytosol

Our species is called Homo sapiens. The first word refers to which taxonomical grouping?

genus

What processes will occur in the presence or absence of oxygen?

glycolysis

Eukaryotes differ from prokaryotes

have a membrane bound nucelus

Intervening sequences that are transcribed, but not translated into protein are called

introns

Which molecule catalyzes covalent bond formation between fragment of DNA?

ligase

The role of enzymes in metabolic reactions

lowers activation energy

Chromosomes are replicated during the

S phase

Which of the following is true concerning a somatic cell mutation? a) only a small group of cells within organisms is affected by the mutation b) all of the gametes carry the mutation c) half of the gametes carry the mutation =

a)

Na+ ion concentrations are higher outside the cell than inside the cell. What type of transport system is required to move Na+ ions in and out of the cells?

active diffusion

Which region of a structural gene contains the information that specifies an amino acid sequence?

transcribed region

The process that produces mRNA from DNA is called

transcription

the true structure of a gene (regulatory region + core promoter structure) and what components (transcription factors) interact with these sites to regulate transcription (and how). Understand how this regulates gene expression.

transcription factors are proteins that bind to the upstream regulatory elements of genes in the promoter and enhancer regions of DNA and stimulate or inhibit gene expression and protein synthesis. They play critical roles in embryogenesis and development.

T or F: (1) substrate level phosphorylation and (2) oxidative phosphorylation create ATP (specifically how these processes add a P + ADP → ATP)

True

A DNA specimen that contains 30% guanine has ____ thymine

20%

T or F: Okazaki fragments are sequences of DNA, most often found on the lagging strand of DNA during DNA replication.

True

Purpose of oxygen during aerobic cellular respiration.

Oxygen is used as the end electron acceptor for the electron transport chain in cellular respiration. It allows electrons to be transferred through the electron transport chain in order to create an electrochemical gradient for hydrogen to create ATP

What type of interactions lead to the formation of protein structure (I, II, III, and IV)

Primary: Simply the sequence of amino acids in a polypeptide chain Secondary: Refers to local folded structures that form within a polypeptide due to interactions between atoms of the backbone - The tertiary structure is primarily due to interactions between the R groups of the amino acids that make up the protein. - Some proteins are made up of multiple polypeptide chains, also known as subunits. When these subunits come together, they give the protein its quaternary structure.

Movement of molecules down their concentration gradient can drive the movement of a different molecule against its concentration gradient

True

Which of the following would NOT be an example of negative feedback control in homeostasis? a) Blood levels of glucose fall during sustained excercise, causing the release of glucagon which stimulates the release of glucose into the blood b) Exposure to cold water cause body temperature to drop. Decreased stimulation of heat receptor causes constriction of blood vessels near the skin and better retention of heat c) Blood volume and pressure drop due to minor bleeding. This decreased pressure causes the kidneys to increase water reabsorption to restore blood volume and pressure d) Glucose levels rise following consumption of a big dessert, triggering release of insulin which causes glucose levels to fall e) During the birth process, stretch receptors in the uterus stimulate the release of oxytocin from the pituitary gland. This hormone stimulates undermine muscle contraction that increases stimulation of the stretch receptor

e

Somatic cell mutations are heritable. True or False?

false

T or F: At prometaphase, the sister chromatids are organized into a single row in the center of the cell

false

T or F: Harnessing light and splitting water occurs in both photosystem I and II

false

T or F: the karoytype of a normal human male would show a total of 23 pairs of homologous chromosomes

false

At the end of meiosis I

the cells are haploid and the homologous pairs are in separate cells.

Outline the steps of DNA replication

the opening of the double helix and separation of the DNA strands, the priming of the template strand, and the assembly of the new DNA segment. During separation, the two strands of the DNA double helix uncoil at a specific location called the origin.