bisc 1112 exam 2

materials such as nutrients, waste products, and gases must be exchanged across the __________________ of animal cells

plasma membranes

a multicellular organization only works if every cell has access to a suitable ___________ environment

aqueous

multicellular organisms with a ________ body have body walls that are only two cells thick, facilitating diffusion of materials

saclike

hierarchial organization of body plans

1. cells

2. tissues

3. organs

4. organ system

covers body surfaces, lines organs and cavities, and contains cells that are closely packed together

epithelial tissue

types of epithelial tissue

• cuboidal (dice-shaped)

• columnar (brick-shaped)

• squamous (tile-shaped)

skin, lining of digestive tract, respiratory tract, blood vessels

examples of epithelial tissue

binds and supports other tissues and organs, sparsely packed cells scattered throughout an extracellular matrix

connective tissue

fibroblasts

secrete fiber proteins

macrophages

engulf foreign particles and cell debris by phagocytes

types of connective fibers

• collagenous (strength, flexibility)

• reticular (join tissues)

• elastic (stretch and recoil)

tendons, ligaments, bones, fat tissue, blood, cartilage

examples of connective tissue

responsible for nearly all types of body movement, muscle cells consist of filaments of the proteins actin and myosin which enable muscles to contract

muscle tissue

types of muscle tissues

• skeletal (voluntary movement)

• smooth (involuntary activities)

• cardiac (heart contractions)

biceps, intestinal walls, heart

examples of muscle tissue

functions in the receipt, processing, and transmission of information

nervous tissue

types of nervous tissue

• neurons (transmit impulses)

• gilal cells (support neurons)

brain, spinal cord, nerves

examples of nervous tissue

endorcine system

• releases signaling molecules that are carried to all locations in the body

• well adapted for coordinating gradual changes that affect the entire body

nervous system

• transmits information along dedicated routes, connecting specific locations in the body

  • suited for directing immediate and rapid responses to the environment

regulator

uses internal control mechanisms to control internal change in the face of external fluctuation

conformer

allows its internal condition to vary with certain external changes

endotherm

• generate heat internally via metabolism

• typically maintain a constant body temperature

• have a higher metabolic rate

• require more food to fuel heat-production processe

ectotherm

• gain heat from external sources

• body temperature varies with environment

• have a lower metabolic rate

• require less food than equally sized endotherms

the body temperatire of a ____________ varies with its environment

poikiotherm

the body temperature of a ________________ is relatively constant

homeotherm

insulation

reduces the flow of heat between an animal’s body and its environment

countercurrent exchange

transfer heat between fluids flowing in opposite directions and thereby reduce heat loss (blood flow in the skin can either increase with heat loss or decrease to lower heat loss)

behavioral responses

seek warm places when cold and orient themselves toward heat sources`

thermogenesis

the adjustment of metabolic heat production to maintain body temperature (increased muscle activity such as moving or shivering)

_____________ thermogenesis takes place when hormones cause mitochondria to increase their metabolic activity

non-shivering

four classes of essential nutrients

• essential amino acids

• essential fatty acids

• vitamins

• minerals

essential amino acids

• all organisms require 20

• plants and microorganisms can normally produce all 20

• animals can synthesize about half from molecules in their diet

• remaining must be obtained from food in prefabricated form

essential fatty acids

• animals can synthesize many of the fatty acids they need

• must be obtained from diet and include certain unsaturated

• animals typically obtain ample amounts from seeds, grains, and vegetables in their diet

vitamins

• organic molecules require in the diet in very small amounts

• thirteen are essential

• fat soluble and water soluble

minerals

• simple inorganic nutrients, usually required in small amounts

• ingesting large amounts of some minerals can upset homeostatic balance

macroevolution

broad pattern of evolution about the species level

____________ changes over large time scales

macroevolutionary

stage one of the chemical and physical process of producing simple cells

abiotic synthesis of small organic molecules

stage two of the chemical and physical process of producing simple cells

joining of these small molecules into macromolecules

stage three of the chemical and physical process of producing simple cells

packaging of molecules into protocells (droplets with membranes that maintain an internal chemistry different from the environment)

stage four of the chemical and physical process of producing simple cells

origin of self-replicating molecules

biotic ingredients

building blocks of organisms

defining characteristics of life

• cell membrane

• DNA

• reproduction

• perception of the environment

• metabolism

• grow to maturity

• adapt and evolve

three domains of life

1. bacteria

2. archaea

3. eukarya

endosymbiotic theory

• large eukaryotic cell engulfed a small prokaryote

• food became friend

• imparted beneficial support

orthologous genes

homology is a result of a speciation event and occurs between genes found in different species

paralogous genes

homology results from gene duplication and occurs between gene copies within a species

horizontal gene transfer

the movement of genes from one genome to another

horizontal gene transfer can occur by

• exchange of transposable elements and plasmids

• viral infection

  • possibly fusion of organisms

undernourishment

• use up stored fat and carbohydrates

• break down its own proteins

• lose muscle mass

• suffer protein deficiency of the brain

• die or suffer irreversible damage

filter feeders

sift small food particles from the surrounding medium

substrate feeders

animals that live in or on their food sources

fluid feeders

suck nutrient rich fluid from a living host

bulk feeders

eat relatively large pieces of food