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CH4 Fundamentals of Biology

•All living things; grow, metabolize, homeostasis, respond, reproduce, and have cellular organization.

Ingredients of Life

•Organic compounds; carbon, hydrogen, and usually oxygen

•Organic compounds; carbohydrates, proteins, lipids, and nucleic acids

Fig. 4.4

Fuel of Life

•ATP

•Photosynthesis

Fig. 4.5

•Respiration breaks down glucose; uses oxygen and produces carbon dioxide and water.

Cells and Organelles

•Prokaryotes and Eukaryotes

•The most primitive cells are prokaryotic; no nucleus, and lack most organelles.

•The cells of eukaryotes; have membrane-bound organelles, a nucleus, DNA in chromosomes

Tab. 4.1

Levels of Organization

Challenges of Life in the Sea

•Habitat include; food, water, shelter, and space

•Plankton are organisms that drift in the water

•Benthic organisms live on the bottom

•Nekton organisms are strong swimmers

Salinity

•Total amount of salt in dissolved water.

For Review:

•Diffusion ; movement of ions and molecules from areas of high concentration to areas of low concentration.

•Osmosis is the diffusion of water across and selectively permeable membrane.

Fig. 4.13

•Marine organisms maintain the proper balance of water and salts

•Internal concentrations change as the salinity of the water changes (osmoconformers)

•Osmoregulators control their internal concentrations to avoid osmotic problems

Osmoregulators

• Marine organisms tend to lose water due to osmosis;

•drink seawater to replace water lost

•produce little urine (concentrated)

•excrete salts through gills

•Freshwater fish have the opposite problem

Fig. 4.14

Fig. 4.15

Fig. 4.16

Temperature

•Temperature plays a major role in determining where different organisms are found in the ocean.

•Organisms are often categorized according to how their metabolism affects their body temperature.

• Ectotherms, cold-blooded or poikilotherms

• Endotherms, warm – blooded or homeotherms

Perpetuating Life

•Heredity

•Asexual Reproduction, single individual can reproduce itself and produce offspring that are genetically identical to the parent.

•For Review;

•Mitosis, produces two daughter cells that are identical to the original cell.

•Meiosis, daughter cells have half the normal number of chromosomes, gametes Sexual Reproduction

Fig. 4.9

Fig. 4.19

Fig. 4.21

Fig. 4.22

Diversity of Life in the Sea

Diversity of Life in the Sea

•Natural Selection occurs when some members of a population survive and reproduce more successfully than others.

•Evolution is the genetic change in the population that results because individuals pass their characteristics on to their young.

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Fig. 4.24

Classifying Living Things

•A species is a population of organisms that share common characteristics, can breed, and are reproductively isolated from other populations

•binomial nomenclature

• Genus species

Tab. 4.2

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