ap bio exam study review

enzymes do:

- increase the rate of a reaction by lowering the reaction's activation energy - form temporary enzyme-substrate complexes -remain unaffected by the reaction

enzymes don't:

-change the reaction -make reactions occur that would otherwise not occur at all

cell theory

1. every living organism is made up of one or more cells 2. the cell is the structural and functional unit of all organisms. smallest unit of life 3. all living cells arise by division of pre-existing cells 4. cells contain hereditary material, which they pass to their offspring during division

Which of the following does not produce genetic variation in sexual life cycles?

Binary fission

Which property of water allows it to move upward from the roots of a tree to its leaves?

Cohesion - As water evaporates from the leaves of trees, the property of cohesion(the attraction to another water molecule) allows the water molecules leaving the plant to pull molecules upward because they are attracted through hydrogen bonds.

If a zygote went through a series of 4 cell divisions, how many cells would be in the embryo?

Each time a cell divides, it become two cells. To calculate the number of cells, square the number of cell divisions; 4^2=16.

how do large particles, such as proteins and polysaccharides, generally cross the plasma membrane into cells?

Endocytosis is the process by which a cell takes in substances by engulfing them in new vesicles formed from the plasma membrane.

Which type of chemical bond involves the transfer of electrons from one atom to another, resulting in oppositely charged ions that are attracted to each other?

Ionic bonds -. Ionic bonds involve the transfer of electrons, causing the atoms to have opposite charges and attract each other.

Which of the following molecules is a carbohydrate?

Lactose- anything that ends in the suffix -ose is a sugar and sugars are carbohydrates.

There are four levels of protein structure. Which level includes the coils of a helix and the fold of B pleated sheets?

Secondary structure

There are several emergent properties of water that contribute to its powerful effect on living organisms. These emerging properties are mostly due to:

The hydrogen bonds linking water molecules together - The hydrogen bonds between the water molecules are able to form, break, and re-form frequently. Water's life-sustaining properties are a result of hydrogen bonding that orders molecules into a higher level of structural organization.

function of the sodium-potassium pump

The sodium-potassium pump exchanges sodium for potassium across the plasma membrane of animal cells by pumping ions against steep concentration gradients.

Which diagram below shows the correct order diffusion of solute in water across a membrane?

There is a net movement of solutes across membranes from an area of high concentration to an area of low concentration until they reach equilibrium.

binary fission is

a type of asexual reproduction used by single-celled eukaryotes, such as amoebas, and prokaryotes.

theodor schwannn

animals are made of cells

During which process do cells enter into programmed cell death, during which time DNA is chopped up, organelles are fragmented, the cell shrinks and parts of the cell are packaged into vesicle and removed by scavenger cells?

apoptosis

Somatic cells

are diploid. If the diploid number is 10, then the organism inherited 5 chromosomes from each parent (the haploid number).

what are enzymes and what do they do?

biological catalysts that speed up chemical reactions. they accomplish this by lowering the activation energy and helping the transition state to form.

can cell membranes fold? and is so why do they fold

cell membranes can fold to meet the demand for resources that occur as growth occurs.

robert hooke

cells exist!

nucleolus

compartment of nucleus that makes ribosomes

function of the rough ER

compartmentalizes the cell for protein synthesis, since it has bound ribosomes on its surface.

apoptosis

controlled suicide of the cell

the endomembrane system

coordinates the sending of proteins from ribosomes to their destinations

negative feedback system acts to.

dampen the initial affect whereas a positive feedback system acts to amplify the initial affect.

each duplicated chromosome had how many sister chromatids?

double the amount of chromosomes

first law of thermodynamics

energy cannot be created nor destroyed. the cell must harvest the energy from somewhere.

second law of thermodynamics

energy transfer or transformation increases the entropy of the universe

exergonic reactions

energy-releasing reactions that are generally catabolic. break down molecules into smaller units and release energy

bound ribosomes found in eukaryotic or prokaryotic proteins?

eukaryotic

eukaryotic cells

have internal membranes that compartmentalize their functions (organelles), isolate specialized environments (pH, molecules), and to increase internal surface area for reactions.

cytokinesis

is the division of the cytoplasm to form daughter cells after mitosis.

catastrophism

is the idea that events in the past occurred suddenly and were caused by different mechanisms than those operating today

signaling molecules are....

molecules that have a specific shape to "fit" in a portion of the receptor protein, like a ket fitting into a lock.

during transmission...

nerve impulses transmit the sensory information through the nervous system via nerve impulses

prokaryotic cells (pro-before, keryon- kernel(nucleus))

onle made of plasma membrane, cytosol/cytoplasm, genetic material (chromosomes), and ribosomes.

water will move by _____ from areas of _____ concentration to areas of _____ concentration

osmosis., high, low

finally, when the brain receives the info, the info gets process, generating a ...

perception

nucleus: function

permanently stores DNA, hosts DNA synthesis (replication) hosts RNA synthesis (transcription)

white blood cells engulf invading bacterium in a process called:

phagocytosis - the process by which cells engulf a particle by wrapping pseudopodia around it and packaging it into vacuoles.

matthias schleiden

plants are made of cells

endocytosis

process by which materials enter the cell via the formation of vesicles.

Which is the correct sequence of mitosis?

prophase, metaphase, anaphase, telophase

endergonic reaction

reactions that require an input of energy. the products have more energy than the reactants.

sensory pathways begin with the...

reception of sensory information, in which the stimulus is detected by sensory cells. negative feed

identify the correct sequence of cell signaling

reception, transduction, activation of cellular response

Which of the following choices represents the correct flow of sensory information in a simple sensory pathway?

reception, transduction, transmission, perception

Which of the following statements correctly describes the difference between saturated and unsaturated fats?

saturated fats tend to be solid at room temp, unsaturated fats are liquid at room temp

ribosomes:

site of translation for protein synthesis. where proteins are assembles from amino acid monomers.

catalyst

substance that speeds up the rate of a chemical reaction

As volume increases,

surface area decreases

tranduction

the binding of the signaling molecule changing the shape of the receptor protein and initiating the process of transduction. Transduction converts the signal to a form that can bring about a specific cellular response.

during metaphase,

the chromosomes are lined up along the metaphase plate, the centrosomes are at opposite poles, the kinetochores of the sister chromatids are attached to microtubules coming from opposite poles.

what determines the function of a protein?

the proteins specific structure - the function of a protein depends on its ability to recognize and bind to some other molecule. Example: antibodies are specific to the invading virus or bacteria, and enzymes are specific to a substrate.

what happens after proteins are made in the rough ER?

the proteins travel to the smooth ER to be packages into vesicles and sent away to the Golgi apparatus. other proteins stay in the smooth Er to become enzymes that break down macromolecules (detoxification)

plasma membrane

the selectively permeable layer of molecules that enclosed the cell

during transduction...

the stimulus is converted to a change in the membrane potential of a sensory receptor

INFO to remember!

the surface area of the membrane has to be sufficiently large for efficient materials exchange to occur.

reception

the target cell detects a signaling molecule coming from the outside of the cell

if a cell is immersed in an isotonic solution, then...

there will be no net movement of water. water will move in and out of the cell at an equal rate.

anton leeuwenhoek

unicellular organisms exist!

golgi apparatus

"finishing" center of the cell. take vesicles delivered from the smooth ER and make final touches, like adding phosphate groups. then sends the finished products to the cell membrane to be excreted out.