BSC 215: Unit One Test

Anatomy studies…

The structure of body parts and their relation to one another

What does the microscopic study of anatomy include?

Cytology (study of cells) and histology (study of tissues)

Physiology is…

The function of body parts

What are the two topics of physiology?

Organ and systemic

Physiology includes the principle of…

Complementary structure and function (form (shape) follows function)

What are the eight characteristics of life?

Homeostasis, organization, metabolism, growth, adaptation, response to stimuli, reproduction, DNA/RNA

Homeostasis:

Maintaining a stable internal environment

Organization:

Living things are made up of units (cells)

What is the unit that living cells are made up of?

Cells

Metabolism:

The combination of chemical reactions in which an organism builds up or destroys materials

Anabolism:

When metabolic processes construct materials

Catabolism:

When metabolic processes breakdown materials (cats break things)

Growth and development:

Single-celled organisms: increase in size

Multicellular organisms: cells divide and develop into different kinds of cells

Adaptation:

Having the capacity to evolve (natural selection, adaptation, evolution)

Response to stimuli:

The ability to detect and react to external (temperature and light) and internal (blood sugar or thirst) stimuli

Reproduction:

Ability to reproduce either asexually (bianary fission) or sexually

Universal genetic code:

DNA is the same genetic code for every living thing on earth

What are the main four levels of organization in the human body?

1. 1. Cells

2. 2. Tissues

3. 3. Organs

4. 4. Systems

Hierarchical approach:

Organism→organ system→tissues→cellular→organelle→molecule→atoms

Tissues:

Groups of similar cells that share a common function

What are the four types of tissues in the human body?

1. 1. Muscle tissue

2. 2. Nervous tissue

3. 3. Connective tissue

4. 4. Epithelial tissue

What is the purpose of the four types of tissues in the human body?

1. 1. Muscle tissue (movement)

2. 2. Nervous tissue (signal)

3. 3. Connective tissue (support)

4. 4. Epithelial tissue (cover)

Two or more tissues working together form…

Organs

Organ systems:

Organs working in tandem to accomplish a common function

Integumentary system:

Skin, hair and nails protect underlying skin

Muscular system:

Skeletal muscle move your bones

Skeletal system:

Bones provide a framework for support and protection

Cardiovascular system:

Heart pumps blood through vessels

Respiratory system:

Lungs absorb oxygen and release carbon dioxide

Urinary system:

Removes wastes from the blood and regulates bodily fluids

Reproductive system (male):

Produces and delivers sperm

Reproductive system (female):

Produces eggs and nourishes and shelters unborn baby

Nervous system:

Receives and sends electrical messages throughout body

Lymphatic system:

Returns leaked fluids to blood vessels and helps get rid of germs

Digestive system:

Breaks down food into nutrients to be absorbed

Endocrine system:

Glands that regulate body function by sending out chemical messengers

Internal environment is determined by physiological variables such as…

Temperature, pH, blood glucose, osmotic balance, blood O2/CO2, calcuim

A feedback system consists of…

A sensor, control center and effector

A sensor in a feedback loop does what?

Detects changes and sends signal to control center

A control center in a feedback loop does what?

Receives information from sensor and sends signals to effectors

An effector in a feedback loop does what?

Responds to signals from control center to effect change in a variable

Homeostatic imbalances:

Disturbances in homeostasis that can lead to disease or death

To prevent homeostatic imbalances, most variables are _________; maintained within a ________ range, close to a _____________

Controlled; narrow; normal value

Negative feedback loop:

Returns regulated variables to within “normal” range of values (pull) →:←

Positive feedback loops:

Increase/reinforce initial stimulus on regulated variable (positive, push, pregnancy)

How are structure and function related?

Complementary; form of structure is always such that best suits its function

___________ drive many physiological processes

Gradients (high→low)

What is required to coordinate body functions?

Cell communication

Endocrine cell signaling:

Act on distant target cells via blood vessels

Paracrine cell signaling:

Local cell-to-cell communication

Autocrine cell signaling:

Self; binds to cell-surface receptors on the same cell that produced it

Juxtracrine cell signaling:

Touch; contact of surface molecules in adjacent cells

Electron charge, location and mass:

-1, orbitals, 0

Proton charge, location and mass:

+1, nucleus, 1

Neutron charge, location and mass:

None, nucleus, 1

Atomic number:

Proton number

Atomic mass:

N(protons) + n(neutrons)

What’s the difference between atomic number and mass number?

Atomic number is the number of protons, while mass is equal to protons+neutrons

Atoms usually consist of…

Protons, neutrons and electrons

Electron shells:

Regions surrounding atomic nucleus where electrons exist

How many electrons can the first, second and third electron shells hold?

Two, eight, eight (satisfied with the octet rule)

Element:

Any substance made up of only one kind of atom

What are the four major elements found in the body?

Hydrogen, carbon, nitrogen, oxygen

Isotopes:

Atoms that differ only in the number of neutrons (and therefore mass)

Atomic weight:

Weighted average mass over all known isotopes of an element

How do isotopes chemically behave?

The same way

Radioisotope:

Physically unstable isotopes that decay over time

Why are radioisotopes unstable?

Contain high levels of nuclear energy and emit this energy as nuclear radiation

Do stable isotopes undergo radioactive decay?

No; they can exist in nature as stable compounds

What are some common uses of radioisotopes?

1. Cancer radiation therapy

2. Radiotracers

3. Treatment of thyroid disorders (iodine-131 treats overactive thyroid tissue)

What is the radioisotope gallium-67 used for?

Medical diagnoses

What is the radioisotope iodine-123 used for?

Diagnose thyroid disorders

What is the radioisotope iodine-125 used for?

Diagnose thyroid disorders and biomedical research

What are the two ways to combine matter?

Mixtures and chemical bonds

Mixture definition and examples:

Different atoms combined retain their chemical properties and can be separated; suspensions, colloids and solutions

Chemical bond definition and examples:

Different atoms combined have new chemical properties and the resulting molecules can only be separated chemically; ionic, covalent and hydrogen bonds

Solutions:

Completely mixed; small, evenly distributed particles will not settle out

Solutions contain a __________ (substance dissolved) and a _________ (substance that dissolves)

Solute; solvent

The solute is ________ if dissolved

Soluble

Suspension:

Mixture containing large, unevenly distributed particles that will settle out when undisturbed (think lava lamp)

Colloids:

Mixture containing small, evenly distributed particles that will not settle out

Why are some atoms chemically reactive and others are not?

Valence shells and the octet rule

Chemical bonds are an ____________ between atoms

Energy relationship

Molecule:

Formed by chemical bonding between two or more atoms of the same element

Compound:

Formed when two or more atoms from different elements combine by chemical bonding

Chemical bonds are formed when valence electrosn of atoms ________

Interact

Octet rule:

Atom is most stable when eight electrons in valance shell

Duet rule matters with atoms with…

Five or fewer electrons

Duet rule:

Atom is most stable when valence shell holds two electrons

Ions:

Charged particles

Ionization can cause…

Cations (+) and anions (-)

Electrolytes:

Substances that ionize in water

What can electrolytes conduct?

Electricity

Ionic bonds:

Transfer of electrons between atoms

Non-polar covalent bonds:

Equal sharing of electrons

Polar covalent bonds:

Unequal sharing of electrons

Hydrogen bonds:

Attractions between polar molecules; very weak

Van de Waal’s forces:

Weak attractions between nonpolar molecules

What is the strongest chemical bond?

Non-polar covalent bonds

What are the three basic types of energy?

1. Chemical

2. Electrical

3. Mechanical