Life Science Flashcards
Cell
Smallest unit of life that is capable of reproduction
Prokaryotes
Bacteria; including Cyanobacteria (blue-green algae)
Eukaryotes
Plant cells and animal cells
Reproduction
Cells in most plants/animals reproduce in six stages:
4 of these stages are called Mitosis (a cell duplicates its own set of chromosomes)
Chromosomes migrate to opposite ends of the cell, cell splits and makes an exact copy of itself in cytokinesis
Mitosis
cell division of parent cell into two daughter cells
Interphase: cell prepares for mitosis
Prophase: mitosis begins as the cell begins to divide
Metaphase: chromosomes align around the equator of the cell
Anaphase: sister chromosomes are formed and move toward opposite ends of the cell
Telophase: mitosis ends and two new nuclei are formed
Cytokinesis: the cell splits into two daughter cells
photosynthesis
converts light energy into chemical energy & gives off oxygen
plants use energy in the sunlight to convert carbon dioxide (6CO2) from the atmosphere + water into simple sugars. chlorophyll is essential
respiration
release of energy by oxidation of sugar
photosynthesis
converts light energy into chemical energy & gives off oxygen
plants use energy in the sunlight to convert carbon dioxide (6CO2) from the atmosphere + water into simple sugars. chlorophyll is essential
respiration
release of energy by oxidation of sugar
nucleus
membrane-enclosed organelle found in all eukaryotic cells
meiosis
process of reductional division in which the number of chromosomes per cell is cut in half
essential for sexual reproduction (occurs in all eukaryotes- animals, plants, fungi)
asexual reproduction
form of reproduction which does not involve meiosis or fertilization. the primary form of reproduction for single-celled organisms (archaea, bacteria)
only one parent is involved
meiosis
process of reductional division in which the number of chromosomes per cell is cut in half
essential for sexual reproduction (occurs in all eukaryotes- animals, plants, fungi, and protists)
digestion
breaking down of chemicals in the body into a form that can be absorbed
circulatory system
organ system that moves nutrients, gases, and wastes to form cells, helps fight diseases, and stabilizes body temp and pH to maintain homeostasis
nervous system
brain, spinal cord, and peripheral nerves
functional unit of the NS is the neuron: nerve cell with short dendrites that carry electrical impulses to the cell body, and a long axon (the outgoing fiber along which the impulse is transmitted further)
hindbrain
cerebellum and medulla oblongata
operates unconsciously and automatically to regulate vital functions (circulation, respiration, excretion, and muscle tension)
cerebrum
largest part of the brain
receives information from the senses and makes conscious decisions
chloroplasts
organelles found in plant cells and eukaryotic algae that conduct photosynthesis
absorb light and use it in conjunction with water and carbon dioxide to produce sugars
mitochondrion
found in most eukaryotic cells & generate most of cell’s supply of ATP (used as a source of energy)
involved with signaling, cellular differentiation, cell death, and control of the cell cycle/cell growth
natural selection
the process by which favorable heritable traits become more common in successive generations of a population of reproducing organisms
unfavorable heritable traits become less common
