INTER PREMID

• ORDER

  All organisms consist of one or more cells with highly

  ordered structures: atoms make up molecules, which

  construct cellular organelles, which are contained

  within cells. This hierarchical organization continues

  at higher levels in multicellular organisms and among

  organisms
• Reproduction

  is necessary on both a cellular and organismal level. For a population to survive, some

  individuals within that population must reproduce.

  Organisms that are multicellular, such as plants and

  animals, also need to reproduce on a cellular level. As

  old cells become damaged or worn out, they must be

  replaced by new cells.
• Asexual

  One individual gives rise to two or more

  offspring that are similar to the parent
• Sexual

  Typically, the two parents contribute a

  gamete (sperm or egg). Gametes fuse to produce

  offspring, which has a combination of the traits of

  both parents.
• Growth and Development

  Development is often described as the processes that

  an organism goes through as it grows and matures
• Autotrophs

  Organisms that are

  capable of making their own chemical energy are referred to as
• Heterotropes

  Others must obtain their chemical energy by consuming other

  organisms. These individuals are referred to as
• Stimuli

  All forms of life responds to
• Homeostasis

  All organisms maintain relatively constant internal

  conditions, different from their environment, a

  process called homeostasis.
• Metabolism

  includes all the chemical activities that take

  place in the organism, including the chemical reactions

  essential to nutrition, growth and repair, and conversion

  of energy to usable forms.
• Homeostasis

  refers to the

  appropriate, balanced internal environment.
• CELLS

  is the smallest unit that is capable of

  performing life functions.
• Cell theory

  was proposed to explain the observation that all

  organisms are composed of cells. It sounds simple, but it is a

  far-reaching statement about the organization of life.
• PROKARYOTIC CELLS

  Do not have structures surrounded by

  membranes
• Prokaryotic cells

  Few internal structures
• PROKARYOTIC CELLS

  • Lack a membrane-bound nucleus

  • Structurally smaller and simpler than eukaryotic cells (which have a

  nucleus).

  • Most ancient and abundant type of cells

  • Prokaryotic cells are placed in two taxonomic domains:

  – Bacteria

  – Archaea

  • Live in extreme habitats
• PROKARYOTIC CELL STRUCTURE

  Have a simple cell structure
• PROKARYOTIC CELL PARTS

  • capsule: slimy outer

  coating

  • cell wall: tougher middle

  layer

  • cell membrane: delicate

  inner skin
• EUKARYOTIC CELLS

  • Contain organelles surrounded by membranes

  • Most living organisms

  • unicellular or multicellular organisms
• Cell Membrane

  • The outer membrane of a

  cell that controls movement

  in and out of the cell

  • Allows nutrients into the

  cell and wastes outside of

  the cell

  • Double layer (Phospholipid

  bilayer)
• Cell Wall

  • Most commonly found in plant

  cells & bacteria

  • Supports & protects cells

  • Made up of Cellulose (plants)

  and Peptidoglycan (Bacteria)
• Nucleus

  • Directs cell activities

  • Separated from cytoplasm by

  nuclear membrane

  • Contains genetic material - DNA
• Cytoplasm

  • Helps in Cell respiration

  • Helps the cell to maintain its shape

  • Acts as store of important chemicals

  • It is the physical basis of all metabolic

  activity

  • Aids to dissolve waste products
• Endoplasmic Reticulum

  • Moves materials around in the cell

  • Smooth type: lacks ribosomes and synthesizes lipids

  • Rough type (pictured): ribosomes

  embedded in the surface and site for Protein synthesis
• Ribosomes

  • Each cell contains thousands

  • Synthesizes proteins

  • Found on the endoplasmic

  reticulum & floating

  throughout the cell
• Mitochondria

  • Produces energy through chemical reactions – breaking down fats & carbohydrates

  • Controls level of water and other materials in cell

  • Recycles and decomposes proteins, fats, and carbohydrates
• Golgi Bodies

  • Protein 'packaging plant'

  • Move materials within the cell

  • Move materials out of the cell
• Lysosome

  • Digestive 'plant' for proteins, fats, and carbohydrates

  • Protects cell by digesting foreign invaders

  • Transports undigested material to cell membrane for removal

  • Cell breaks down if lysosome

  explodes
• Vacuoles

  • Membrane-bound sacs for

  storage, digestion, and waste

  removal

  • Contains water solution

  • Help plants maintain shape
• Chloroplast

  • Usually found in plant cells

  • Contains green chlorophyll

  • Where photosynthesis takes

  place
• Biology

  ▪ Study of Life

  ▪ Study the origins and history of life and once-living things

  ▪ Study the structures of living things

  ▪ Study how living things interact with one another

  ▪ Study how living things function
• Importance of Biology

  1. Biology is relevant to our everyday experience

  2. Biology can be controversial.
• Science is a body of knowledge based on the study of nature.
• The Nature of Science

  ▪ Science is a body of knowledge based on the study of nature.

  ▪ The nature, or essential characteristics, of science, is scientific inquiry.

  ▪ Scientific inquiry is both a creative process and a process rooted in unbiased observations and experimentation.
• theory

  is an explanation of a natural phenomenon supported by many observations and experiments over time.
• Uses Scientific Theory

  – A theory is an explanation of a natural phenomenon supported by many observations and experiments over time.

  – The results are always the same.
• Expands Scientific Knowledge

  – Most scientific fields are guided by research that results in a constant reevaluation of what is known.

  – This reevaluation often leads to new knowledge that scientists then

  evaluate.
• Challenges Accepted Theories

  – Scientists welcome debate about one another’s ideas.

  – Sciences advance by accommodating new information as it is

  discovered
• Questions Results

  – Observations or data that are not consistent with current scientific

  understanding are of interest to scientists.

  – These inconsistencies often lead to further investigations.
• Tests Claims

  • Science-based information makes claims based on a large amount of

  data and observations obtained from unbiased investigations and

  carefully controlled experimentation.

  • Conclusions are reached from the evidence.