Biology 2201 Unit 2 Test 1

Biogenesis

the idea that life comes from life

Abiogenesis

The idea that life rises from nothing

How is biogenesis a paradigm shift

because the majority of scientists/people believed for hundreds of years that abiogenesis was correct, until Redi and Pasteur.

Cell theory

1. All living organisms are composed of one or more cells.
2. The cell is the basic unit of structure and organization in organisms.
3. Cells arise from pre-existing cells.
4. The activities of a multicellular organism depend on the activities of all its cells.

Calculating total magnification

take ocular lens power (10x) times the objective lens power ex: 10 × hp (40)= 400

Calculating Field of View Medium Power

Medium Power FOV = (Lower Power FOV x Magnification of Low Power) ÷ Magnification of Medium Power

Calculating Field of View High Power

High Power FOV = (Lower Power FOV x Magnification of Low Power) ÷ Magnification of High Power

Prokaryotic Cell

No nucleus, smallest living cells, simple internal structure, no membrane-bound organelles

Bacteria cells are...?

Prokaryotic

Animal and Plant cells are...?

Eukaryotic

Eukaryotic cell

Have a nucleus, larger (than comparison to prokaryotic), complex internal structure, have membrane-bound organelles

Animal vs. Plant Cells

Plant cells have cell walls and chloroplasts while animal cells don't. Plant cells have one vacuole, animal cells have many.

Cell Membrane

A cell structure that controls which substances can enter or leave the cell. A phospholipid bilayer that encloses the cells contents.

Cell wall

A rigid layer of nonliving material that surrounds the cells of plants, bacteria and fungi. Surround cell membrane. Not all made of the same material.

Cytoplasm

The cells contents, including all the cells organelles except the nucleus.

Cytosol

Is the jelly-like fluid in which all the organelles are suspended in a cell.

Nucleus

Control center of the cell. Site of DNA. DNA contains all the instructions for the cells activities. Surrounded by its own porous nuclear-membrane envelope.

Nucleolus

Inside the nucleus. Site of ribosomes production.

Ribosomes

Produced in the nucleus. Responsible for building proteins. Some ribosomes are known as free-ribosomes, as they float individually in the cytoplasm. Others are attached to endoplasmic reticulum.

Endoplasmic Reticulum Smooth

Connected to the nucleus, lacks ribosomes, funtions to make lipids and release calcium.

Endoplasmic Reticulum Rough

Connected to the nucleus, studded with ribosomes. functions to make proteins.

Vesicles

Small containers used for storage and transport in cells.

Lysosomes

Specialized vesicles that contain enzymes used to break down proteins, fats and nucleic acids (i.e. cellular waste products)

Golgi apparatus

Processes proteins made by the ER and packages them in vesicles for transport inside or outside of the cell. Is made of a stack of flattened membrane bound sacs.

Vacuoles

Fluid-filled sacs that act as storage compartments for food, water, and waste products. Plant cells often have a large central vacuole whereas animal cells have several smaller vacuoles.

Mitochondria

"Powerhouse" of the cell. Responsible for producing ATP (cellular energy) through the process of cellular respiration. The more energy a cell needs, the more mitochondria it tends to have.

Chloroplast

Found in plant cells and eukaryotic protists. Site of photosynthesis. Contains the green pigment chlorophyll.

Francesco Redi

Disproved spontaneous generation. Conducted one of the first controlled experiments that supported biogenesis. Worked/used meat in jars, some covered/some not. Made observations regarding whether or not maggots would develop.

Louis Pasteur

He conducted experiments that finally disproving abiogenesis. He used flasks with S-shaped necks to show that microorganisms come from other microorganisms, and do not appear by spontaneous generation.

Anton Von Leeuwenhoek

Inventor of the first microscopes. 1600's.

Robert Hooke

Used a compound microscope to observe slices of cork. Observed empty vessels he called "cells".