BIO 111 Exam 1 Practice

The Culture of Science

Science is an intensely social activity, both collaboration (cooperation) and competition characterize scientific culture

All living things share 5 fundamental characteristics

(2 as of now)

1\.) All organisms are made up of Cells

4\.) All organisms acquire and use Energy

Adenosine Triphosphate (ATP)

The form of chemical energy that is required for reactions to take place inside of the cell.

Cell Theory

The understanding of cells

Theory

a rigorously tested and supported explanation (pattern + process)

Theory of Evolution by Natural Selection

all organisms are made of cells (pattern) and all cells come from preexisting cells (process)

3 theories form the framework for modern biological science:

\- The cell theory (Bio. 111) - The theory of evolution by natural selection (Bio.112 and Bio. 211)- The chromosome theory of inheritance (Bio. 111)

How is hereditary information transmitted from one generation to the next?

DNA, chromosomes and genes

Two main types of cells:

Prokaryotes and eukaryotes

Prokaryotes

Domains: Archaea and Bacteria

* single-celled
* “before kernel”
* not membrane-bound
* ten times smaller than eukaryotes
* DNA is not enclosed in the nucleus; in the region called the nucleoid

Eukaryotes

Domain: Eukarya

* single-celled or multicellular
* “true-kernel”
* membrane-bound nucleus and organelles
* provides more S.A. to move quickly in a large volume
* complicated exoskeleton

Broadest phylogenetic classification

Domain

Cell Characteristics

* Move,
* Metabolize (acquire and use energy),
* Respond to the environment,
* Reproduce, and
* Descend from pre-existing cells, and over time these lineages of cells evolve

Nucleic acids

what chromosomes are made of (genetic information)

Proteins

made by ribosomes that are either free in the cytoplasm or attached

Carbohydrates

provide energy, carbon, identity/ recognition

Lipids

make up the plasma membrane and other structures

Kernel

nucleus

Nucleoid

The central region in a prokaryotic cell where the DNA is located. It is not enclosed by a membrane and is responsible for controlling the cell's activities.

symbiotic

living together with another organism

mutualism

A type of symbiotic relationship where both species benefit from each other's presence.

Plasma membrane

A selectively permeable barrier that surrounds the cell, controlling the movement of substances in and out.

Plasmid

It can replicate independently from the chromosomal DNA and can transfer genetic material between different bacteria. Plasmids often carry genes that provide advantages to the bacteria, such as antibiotic resistance.

Cytoplasm

A gel-like substance found inside cells. It holds organelles in place and facilitates cell processes.

Cell wall

Structure outside the cell membrane that provides support and protection to plant cells.

Ribosome

A cellular structure responsible for protein synthesis. It translates genetic information from DNA into proteins.

NPC,L

* Nucleic Acids
* Proteins
* Carbohydrates
* Lipids

The Nucleus

* The central part of a cell that contains genetic material
* makes up the rRNA for transport and use in the cytoplasm
* double membrane (nuclear envelope)
* semi-permeable
* loosely packed chromosomes

Chromosomes

* coiled


* only 1
* Inside the nucleus with DNA that carries genetic information
* made of chromatin
* Shape changes as the cell divides

Supercoiled Chromosomes

DNA structure where the double helix is twisted upon itself, forming a tightly coiled shape. (90% of the time)

Relaxed Chromosomes

DNA structure where it is in a linear form. (10% of the time)

Chromatin

The complex of DNA and proteins found in the nucleus of a cell, which condenses to form chromosomes during cell division.

Ribosomes

* Made of rRNA and proteins
* 1 large and 1 small sub-unit. (come together to make proteins)
* synthesize proteins in two different locations
* free (cytoplasm)
* attached (\[ER\] ore the nuclear envelope)

Endomembrane System

* ER - rough and smooth
* Golgi apparatus
* Lysosomes (animals only)
* Continuous or connected by vesicles

Rough ER

* Ribosomes bound to it
* proteins from ribosomes finish folding here

Lumen

Inside space within the cells organelles

Smooth ER

* No attached ribosomes
* Synthesizes lipids
* Testes and ovaries need lots of this for hormone production

Golgi Apparatus

* shipping and receiving center
* made of sacs called cisternae
* Functions:
* the receiving cis side gets vesicles from the ER, forming new cisternae
* modifies and manufactures
* the shipping trans side sorts and packages materials with molecular barcodes

Cisternae

Membrane sacs found in the ER and Golgi apparatus. They play a crucial role in the processing, modification, and transport of proteins and lipids within the cell.

Lysosome

* (animals only)
* interior is acidic for digestion

Vacuole

* (plants and fungi only)
* storage of water and ions
* huge, in a fixed place in the cell
* can sometimes digest

Peroxisomes

Organelles in which oxidation reactions occur sequestering H2O2 (hydrogen peroxide)

Mitochondria

* energy powerhouse of the cell


* can make their own proteins because of the DNA and ribosomes it contains
* in all eukaryotic cells (fungi, plants, animals, and protists)
* double membrane system
* produces ATP and oxygen through cellular respiration

Chloroplast

* (plants only)
* convert sunlight energy into chemical bond energy in the form of carbohydrates
* can make their own protein b/c DNA and ribosomes it contains
* multiple membranes

Cytoskeleton

Network of protein filaments that give shape, support, and movement to cells. Made up of microtubules, microfilaments, and intermediate filaments.

Actin Filaments

(smallest)

* responsible for cytokinesis and cell crawling

Intermediate Filaments

Maintain cell shape and also anchor the nucleus

Microtubule Filaments

(largest)

* move chromosomes by building and falling apart at the other end (railroad)

Transmission Electron Microscope (TEM)

Electrons pass through the sample, creating a detailed 2D image

Scanning Electron Microscope (SEM)

Electrons bounce off the sample, creating a 3D sample

Polymerize

to combine or cause to combine to form a polymer.

* actions or α and β coming together to form filaments.

Depolymerize

break (a polymer) down into monomers or other smaller units.

* actions or α and β coming breaking apart

Centrosome

(only in animal cells)

* organize the microtubules

Microtubule Transport

transport membrane vesicles and organelles through the cytoplasm of eukaryotic cells. 

* ADP releases
* ATP enters
* ADP - Pi (hydrolyze)
* (repeats)

Centriole

help to arrange the microtubules that move chromosomes during cell division to ensure each daughter cell receives the appropriate number of chromosomes.

ATP Bond Break

Massive amounts of energy are released when one bond is broken in the phosphate group and one inorganic phosphate is released. This results in ADP

ADP

Adenosine Diphosphate

Aquaporins

A type of protein is a part of facilitated diffusion, where lots of water molecules pass through the cell membrane so osmosis can occur faster.

Endosymbiosis

A symbiotic relationship where one organism lives inside the other

The benefit of engulfing a Mitochondrion

Gains energy/ ATP for survival

The benefit of engulfing Chloroplast

Photosynthesis provides sugar, making it advantageous to absorb to engulf to have a food source for the cell.

Polar

partial charge due to unequal sharing of electrons

Nonpolar

no charge, electrons shared equally

Ions

full charge due to the actual GAIN or LOSS of electrons

Phospholipid Bilayer

Acts as a barrier to the passage of molecules and ions into and out of the cell. 

* Size and charge can affect the diffusion rate across the membrane
* contains proteins

Ground Substance

helps the cell resist compression

* a part of the extracellular matrix

Fibers

helps the cell resist tension

* a part of the extracellular matrix

Extracellular Matrix (ECM)

The ECM provides structural and biochemical support to cells.

Collagen

provides strength and also regulates cell adhesion, supports chemotaxis and migration, and directs tissue development.

* **a part of the extracellular matrix**

Diffusion

the movement of a substance traveling down its concentration gradient

* high to low concentration
* passive transport

Facilitated Diffusion

molecules going through a protein channel b/c they can’t pass through the semi-permeable membrane if they are charged ions or polar molecules.

Osmosis

Water molecules travel from an area of high concentration to a lower concentration.

* movement from low solute concentration to high solute concentration
* high water ψ potential → Low water ψ

\

Hypertonic

high solute concentration

Hypotonic

low solute concentraion

Isotonic

equal solute concentration

Water potential

measurement of potential energy in water

* solute and pressure potential
* formula - water ψ = pressure ψ + solute ψ

Homeostasis

Stable equilibrium maintained by all living systems

Active Transport

Force molecules to move against their concentration gradient by using ATP/ energy.

Sodium Potassium Pump

To pump sodium out of the cell and potassium onto the cell

* 3 sodium out
* 2 potassium in

Resting Membrane Potential

The electric potential energy that results from separating opposite charges across the membrane when those charges aren not stimulating the cell.

Electrochemical Gradient

allow cells to control the direction ions move across membranes

Adjacent Cell Connection (animal)

* Tight Junctions
* Desmosomes
* Gap Junctions

Adjacent Cell Connection (Plant)

Plasmodesmata

* connect + direct communication
* smooth ER of two cells connect through cell wall

Tight Junctions

forms an adhesion complex between two neighboring cells, serving as a tight seal between the cells

Desmosomes

mediate cell-cell contact and strong adhesion

* Requires
* membrane proteins
* anchoring proteins
* intermediate filaments

Gap Junctions

Allows for direct connection and communication, creating open channels between cells.

* ex.)heart cells

Most common elements in humans

* Hydrogen - H
* Oxygen - 02


* Carbon - C
* Nitrogen - N2

What is circled

Mass number (picture)

What is circled

Atomic number (picture)

Mass #

\# of protons + neutrons

Atomic #

\# of protons

Valence Electrons

electrons in the outermost shell of an atom

Covalent Bonds

a chemical bond that occurs when atoms share electrons to form electron pairs

Nonpolar Covalent Bonds

atoms share electrons equally

Polar Covalent Bonds

atoms don’t share electrons equally

* one atom has more pull, or attraction

Electronegativity

how likely an atom is to attract electrons when forming a chemical bond

FON

Ionic Bonds

made from atoms or ions with a charge

* electrons are gained or lost

Hydrogen Bonds

An attraction between two atoms already in chemical bonds. One of the atoms is hydrogen, and the other atom can be any electronegative atom.