Life Science Flashcards
Things that have physical entities and biological processes (such as homeostasis, cell division, cellular respiration, and photosynthesis)
Living things/animate
Things that do not have biological processes
Nonliving things/inanimate
What are the three components of Cell Theory?
1) All living things are composed of cells
2) The cell is the smallest unit of life
3) All cells come from pre-existing cells
Describe the organization of life (in order of smallest to largest)
Cells < Tissues < Organs < Organ Systems < Organisms
A unicellular organism that lacks a nucleus, mitochondria, or any other membrane-bound organelle. DNA floats freely throughout the cell.
Prokaryote
A multicellular organism that contains a nucleus, mitochondria, and membrane-bound organelles.
Eukaryote
What are the two domains of prokaryotes?
Archaea and Bacteria
Structures within the cell membrane or cell wall
Organelles
Fluid, permeable outside covering of the cell. Called a cell wall in plant cells, and it is rigis.
Cellular Membrane
Controls the rest of the cell. This is where the DNA lives in eukaryotic cells.
Nucleus
Energy source of the cell; they use aerobic respiration to generate ADP, which is used throughout the cell as a source of chemical energy.
Mitochondria
the gelatinous liquid that fills the inside of a cell. It is composed of water, salts, and various organic molecules.
Cytoplasm
What are the main differences between plant and animal cells?
1) Plant cells have a cell wall, which provides structure and support, while animal cells have a plasma membrane.
2) Plant cells contain chloroplasts, which are responsible for photosynthesis, while animal cells do not.
3) Plant cells have a larger central vacuole, which stores nutrients and waste, while animal cells have smaller, more numerous vacuoles.
4) Plant cells are autotrophs (make their own food) and do so through photosynthesis. Animal cells are heterotrophs and need to consume food which they will use to create ATP/energy through cellular respiration.
Photosynthesis formula
CO2 + H20 + light = carbohydrates + O2
Cellular respiration formula
Carbohydrates + O2 = CO2 and H20
Form of reproduction that involves two parents, where each parent contributes a gamete to the process.
Sexual reproduction
Sex cells (in males = sperm, in females = ova)
gametes
Involves only one parent. There are four main types.
Asexual reproduction
When a single parent cell doubles its DNA, then divides into two cells. Usually occurs in bacteria.
Binary fission
When a small growth on the surface of a parent cell breaks off to continue growing into adulthood. Typically occurs in yeast and some animals (like corals and hydras).
Budding
When a piece of an organism breaks off, and those pieces develop into a new organism. Happens with starfish and planaria.
Fragmentation
When an embryo develops from an unfertilized cell. This occurs in invertebrates as well as in some fish, amphibians, and reptiles.
Parthenogenesis
Type of cell division- is a series of steps in creating an identical cell from another cell
Mitosis
Stage where the cell prepares for division. It plumps up and replicates its DNA within its nucleus.
Interphase
Stage of cellular replication where the DNA tightly coils into chromosomes to make splitting efficient. The nuclear membrane dissolves. The microtubes or spindle fibers move to opposite sides of the cell.
Prophase
Stage of cellular replication where the chromosomes (tightly coiled DNA) move to the middle of the cell. The spindle fibers attach to each chromosome.
Metaphase
Stage of cellular replication where the spindle fibers begin to pull apart the chromosomes, bringing them to opposite sides of the cell for efficient splitting.
Anaphase
Stage of cellular replication where, with the chromosomes at either side of the cell, the two new cells pinch off, forming two identical sister cells of the original cells.
Telophase
When the cell separates into two cells during the final stage of mitosis.
Cytokinesis
Type of cell division that ensures humans have the same number of chromosomes in each generation. It is a two-step process that reduces the chromosome number by half to form sperm and egg cells.
Meiosis
How many chromosomes are in a cell? How many pairs?
each cell in the human body has 23 pairs of chromosomes (46 total chromosomes)
(‘three bodies’) means the affected person has three copies of one of the chromosomes instead of two. This means they have 47 chromosomes instead of 46.
Trisomy
Humans usually have 46 total chromosomes, with ___ sex chromosomes that determine sex and ___ chromosomes that direct other factors, such as growth and function.
2; 44
The molecule inside cells that contains the genetic information responsible for the development and function of an organism.
DNA