biology 31, 34, 44, 45

Tissue

A group of specialized cells of the structure and function

Organ

Composed of two or more tissues working together to perform a particular function

Organ system

Composed of several organs working together to perform a general process

Epithelial Tissue

Consists of tightly packed cells that form a continuous layer; covers surfaces (skin) and body cavities; forms glands; usually has a protective function, but can be modified for secretion, absorption, excretion, or filtration; the cells are connected by junction proteins; cells attached to basement membrane made of proteins that anchors epithelium to underlying tissues

Connective Tissue

Widely spaces cells; binds and supports body parts; most abdunant and widely distributed tissue in the body; has specialized cells, ground substances and protein fibers; ground substance is not made of cells; can be solid or liquid; protein fibers can be collagen, reticular, or elastic; fibrous connective tissue make up fat tissue, tendons, and ligaments; supportive connective tissues are cartilage and bones; fluid connective tissue is blood.

Muscular Tissue

Composed of muscle cells called fibers that are specialized to contract; muscle tissues responsible for body movement and generation of body heat; skeletal muscles are attached to bones and are voluntary; smooth muscles line internal organs and are involuntary; cardiac muscle lines wall of the heart and is involuntary

Nervous Tissue

Receives stimuli and transmits nerve impulses; contains nerve cells (neurons) and supporting cells called neuroglia; nerve cells specialized to conduct impulses; allows communication between brain and rest of body; nerve cells have dendrites (conducts impulses toward cell body), cell body has nucleus, and axons (conducts impulses toward impulses away from the body)

Epidermis

Composed of stratified(multiple layers), squamous(flat) epithelium(several layers of flat, closely packed cells); most cells are dead and filled with a protein called keratin; deepest layers have actively dividing cells that replace cells that flake off

Dermis

Deeper and thicker; composed mostly of dense fibrous connective tissue; contains all living parts (sweat glands, oil glands, hair roots, blood vessels, nerves)

Location and Contents of the Dorsal Cavity

Contains the brain and spinal cord; located in the back

Location and Contents of the Ventral cavity

Divided by diaphragm into thoracic cavity(heart and lungs) and abdominal cavity(digestive system organs)

Briefly describe the four basic functions of the digestive system

Ingestion: taking in food

Digestion: breaking food down into small molecules that can cross plasma membranes; mechanicals digestion physically breaks food down; chemical digestion chemically breaks food down into monomers

Absorption: moving molecules from digestive organs into body

Elimination: ridding body of undigestible remains

List in order the organs of the digestive (gastrointestinal) tract of humans.

Mouth: oral cavity; takes in food; teeth physically break down food into smaller pieces; salivary glands secrete enzyme that starts chemical digestion of starch 

Pharynx: common tube for respiratory system and digestive system

Esophagus: tube connecting pharynx with stomach

Stomach: mainly for food storage; some mechanical digestion occurs; some protein digestion occurs

Small Intestine: site of most chemical digestion and absorption; wall of small intestine contains circular folds, villi, and microvilli to increase surface area for digestion and absorption

Large Intestine: larger in diameter than small intestine, shorter; includes cecum, colon, rectum, anus; stores indigestible material until it is eliminated as feces; site of water absorption and vitamin absorption

Rectum: Stores and regulates elimination of feces

Anus: outlet of the digestive tube

Briefly describe the functions of the liver, gallbladder and pancreas in digestion.

Gallbladder: stores bile between meals

Liver: in digestion it secretes bile; bile helps to digest fats

Pancreas: in digestion, it secretes enzymes that digest carbohydrates and other enzymes that digest proteins

Ecology

The study of the interaction amount organisms and with their environment

Habitat

The place where an organism lives

Population

All the organisms belonging to the same species within an area at the same time

Community

All the populations interacting in a specific area

Biotic potential

The highest possible growth rate for population: depends on for factors

4 Factors that determine biotic potential

1. Number of offspring per reproductive event that survive to reproductive age

2. Amount of competition within the population

3. Age of the members of the population along with the number of reproductive opportunities they have available

4. Presence of disease or predators

carrying capacity.

The maximum number of individuals of a given species the community can support with available resources

Opportunistic Populations

live in fluctuating environments, density-independent factors keep population low, tend to be small individuals, short life span, fast to mature, many offspring, little or no care of offspring, many offspring die before reproducing, early reproductive age

Equilibrium Populations

Live in stable environments, carrying capacity determines population size, tend to be large individuals, long life span, slow to mature, few and large offspring, much care of offspring, most young survive to reproductive age.

Symbiosis

close association between two different species over long periods of time

Parasitism

One organism feeds on another organism but does not kill it immediately

Commensalism

• One organism benefits; other unaffected

Mutualism

both organisms benefit

Batesian Mimicry

one species with weak defenses resembling another species with strong defenses

Mullerian Mimicry

several species with equally strong defenses resembling each other

Ecological succession

 a change within a community involving a series of species replacements

Primary Succession

Starts with bare rock; rock eroded into soil and supports grasses. As plants grow and die’ the soil gets thicker to support bigger and longer living plants; bigger and longer living plants means bigger and longer living animals

What is a food web

Diagram showing feeding relationships in a community