Bio Keystone Prep

How many pairs of chromosomes do humans have?

23

A human has how many chromosomes?

46

Which of the following is essential to proper functioning of all prokaryotic and eukaryotic organisms?

ATP

Which statement best describes the role of ATP in a living system?

ATP captures and transfers energy released by the breakdown of glucose

Carbohydrates and proteins are two types of macromolecules. Which functional characteristic of proteins distinguishes them from carbohydrates?

Ability to catalyze biochemical reactions

What does heterozygous mean?

An organisms that has different genes for a trait

A student made an observation about a plant. Which statement is an observation that the student most likely made?

At 10 am the plant's leaves were tilted toward the sun

Which conclusion is best supported by the presence of ribosomes in prokaryotes and eukaryotes?

Both prokaryotes and eukaryotes make proteins to perform life functions

Why does water move from the roots to the leaves of plants?

Capillary action pulls the water like a chain

Which statement best describes why most biological macromolecules contain carbon?

Carbon can share electrons with up to four different atoms and form three types of bonds

What's the equation for photosynthesis?

Carbon dioxide + water -> oxygen + glucose

Photosynthesis is a process that helps cycle matter through the environment. Which statement best explains the role of photosynthesis in the carbon cycle?

Carbon dioxide is absorbed from the air, and carbohydrates are produced

Releases carbon dioxide

Cellular respiration

Uses that sugar (glucose)

Cellular respiration

Tendency of molecules of the same to stick together

Cohesion

Orchids living in tropical rainforests often grow on the branches of trees to access sunlight. The trees are not affected by the orchids. Which term best classifies the relationship between the orchids and the trees?

Commensalism

Carbon dioxide and oxygen are molecules that can move freely across a plasma membrane. What determines the direction that carbon dioxide and oxygen molecules move?

Concentration gradient across the plasma membrane.

Which characteristic is shared by all prokaryotic and eukaryotic organisms?

Contains genetic material

Which sequence of events correctly describes the process of DNA synthesis

DNA - transcription - mRNA - protein is produced

Before cellular division the cell duplicates its DNA so the daughter cells contain complete copies of DNA. Which characteristic of DNA makes it most suitable as a molecule?

DNA is made of two complementary nucleotides strands

Energy pyramids describe food and energy relationships within an ecosystem. Which factor most likely limits the number of levels an energy pyramid can have?

Energy loss between each level of organisms

Which statement best compares eukaryotic and prokaryotic cells.

Eukaryotic cells contain membrane bound organelles, and prokaryotic cells don't

A scientist determined the average air temperature in an area increased during an observed period of time. The area included several small ponds. Which change to the water cycle most likely occurred in the area during the observed period of time?

Evaporation increased

Which example is an activity that a fish most likely uses to maintain homeostasis within its body?

Exchanging gases through its gills to regulate oxygen levels

Lungs and capillaries both have porous linings that allow certain substances to move into or out of the structures. Which function do these porous linings most likely serve?

Gas exchange

A specific genetic disorder is caused by non disjunction. Which statement describes how the genetic disorder occurs?

Incomplete chromosome separation leads to gametes with an abnormal number of chromosomes

A type of inheritance pattern that's a mixture of both traits

Incomplete dominance

OG : ATC CAT Mutation : ATC GCAT What mutation happened?

Insertion

In the human body the steroid aldosterone is released by the adrenal glands to help regulate sodium and potassium levels. This regulation helps control blood pressure and balance fluids in blood. Which statement best describes this process of regulation within the body?

It is a feedback system that maintains homeostasis

How does a mitochondria facilitate the movement of some materials between cells?

It supplies the energy needed for moving molecules through membranes

Which statement describes how the Yawunik most likely interacted with other organisms in its environment?

It was a predator that obtained energy from other consumers

A molecule is produced within a ribosome in a cell. What most likely happens to the newly formed molecule once it's inside the Golgi apparatus of the cell?

It will be modified before it's packaged for transport

What is the main purpose for initiating the production of folding helpers in a cell

Maintaining homeostasis

Mitosis and meiosis are processes by which animal and plant cells divide. Which statement best describes a difference between mitosis and meiosis?

Mitosis produces genetically identical daughter cells

Which process best describes the assembly of proteins from amino acids?

Monomers are linked to form a polymer

And organism carries out both photosynthesis and cellular respiration. Which statement describes a difference between the two processes?

Only photosynthesis changes light energy into chemical energy

Which statement best describes how amino acids become polymers?

Peptide bonds link amino acids together as proteins form

What is the cell membrane mostly made of?

Phospholipid belayed and proteins

Produces sugars (glucose)

Photosynthesis

Releases oxygen

Photosynthesis

Which sequence best orders ecological categories from the one with the fewest individuals to the greatest?

Population, community, ecosystem, biome

- chromatin has condensed into visible chromosomes - nuclear envelope has disappeared Which stage of the cell cycle does the describe?

Prophase

What type of marcomolecule is an enzyme?

Proteins

Two closely related shrimp species have habitats and niches that partially overlap. Which factor most likely caused the divergence of the Shrimp into separate species?

Reproductive isolation

What do cells of E.Coli bacteria and an elephant have in common?

Ribosomes that assemble protein

What property of water helps moderate the earth's temperature?

Specific heat capacity

Which statement best explains why the carotenoid gene has been present in pea aphids for millions of years?

The HGT process introduced a benefit for survival and led to greater reproductive success in pea aphids with the carotenoid gene.

Which property of water is most responsible for plants being able to transport water from their roots to their leaves?

The attraction between molecules

Which statement explains why a single enzyme is unable to regulate a variety of reactions?

The binding of a substrate and an enzyme is specific

Which statement best compares a carbohydrate and a nucleic acid?

The bonds in a carbohydrate store energy, and the sequence of nucleotides in a nucleic acid stores genetic information

Which event describes cellular activities that would be observed during cytokinesis in an animal cell?

The cytoplasm of the parent cell divides following the division of the nucleus

What is a phenotype?

The expression of a trait, physical appearance

A mutation in a parent's genetic code impacts offspring. Which statement most likely describes the mutation?

The mutation alters the function of the protein made by the gene

Oak tree hoppers are parasites of trees. Which statement describes the relationship between the tree and the oak treehopper?

The oak treehopper benefits from the tree, while the tree is harmed (parasitism)

DNA replication in a eukaryotic cell occurs in the presence of the enzyme DNA polymerase. Which effect is most likely caused by a pH change in the cell nucleus?

The rate of DNA replication will decrease

Which statement best describes both mitochondria and chloroplasts?

They both contain their own DNA and are involved in energy conversions

Enzymes need certain environmental conditions in order to function properly. What happens when enzymes are heated to a high temperature?

They denature

Which statement best describes how scientists use the Yawunik fossil evidence to support its evolutionary relationship to other arthropods?

They interpret the similar anatomy of other arthropods

Which statement best describes a function of the proteins embedded in the plasma membrane of cells?

They selectively allow certain particles into and out of the cell

A scientist wants to make a change to a genetic code that will lead to the removal of one amino acid from the sequence of a protein. Which genetic material should the scientist remove?

Three nucleotides

Which statement best explains how organisms pass traits on to their offspring?

Traits are inherited by the transfer of genetic material from parent to offspring

Which statement best describes an effect of the low density of frozen water in a lake?

When water in a lake freezes, it floats, providing insulation to those organisms below

The part of the enzyme that the substrate bonds to is called .....

the active site