Science Unit B Flashcards
Basic living things
• are made of cells • need energy • grow and develop • respond to the environment • reproduce • have adaptations for their environment
Organisms
All living things, or organisms, have all of these characteristics. Non-living things may have some of these characteristics
Cells
The cell is the basic unit of life. A cell can perform all the processes that life depends on. All organisms are made up of at least one cell, and every cell comes from another cell.
What size are cells
Cells are usually microscopic in size, so a single-celled organism is almost always tiny. A large organism, such as a tree, can be made of trillions of microscopic cells
Non-living things
Non-living things are not made of cells. However, there are exceptions. Cells are found in non-living material if that material was alive at one time.
Nutrients
are substances that provide the energy and materials that organisms need to grow, develop, and reproduce.
Metabolism
For an organism to stay alive, there has to be a balance between these energy-using processes and the energy-creating processes. The sum of all the different processes that happen in an organism is called the organism’s metabolism.
Stimulus
is anything that causes a response in an organism. Jumping out of the way of the car is a reaction, or response, to a stimulus.
Adaptions
is a characteristic that allows an organism to live in its environment. Animals and plants have many adaptations.
Structures
Organisms have developed many different ways of doing these tasks and have developed different body parts, or structures, to do them.
Function
Each structure is used for a specific function, which means it carries out a specific task
Organ system
The organs that make up each organ system work together to perform a certain task or function.
Capillaries
These blood vessels were later called capillaries, from the Latin is called Hair
Cells
are the smallest known functioning units of life. All organisms must be made of at least one cell.
Tissues
Tissues that work together for a common purpose form organs
Organ system
is a group of organs that work together for a common purpose in order to keep you alive.
Organelles
Within each cell, there are a number of specialized structures called organelles that carry out specific functions. One way to think about cells’ organization is to think of them as living factories, making all the things necessary for them to live.
Nucleus
a “command center” that directs all cellular activities such as movement, growth, and other life functions
mitochondria
the “powerhouses” of the cell where chemical reactions occur that convert the
energy the cell receives into a form it can use
Cell membrane
a “controllable gateway” that lets needed materials in and waste materials out
Vacuoles
the “storage rooms” where nutrients, water, or other substances can be stored by the cell. Plant cells tend to have just one big vacuole, and animal cells have many small vacuoles
Cytoplasm
the “kitchen” of the cell. It contains the nutrients required by the cell to maintain its life processes.
cell wall
the “frame” of the cell. Found in plant cells but not in animal cells, it provides strength and support to plants
Chloroplasts
the “solar panels” of the cell. They are found in the cells of the green parts of plants. They carry out photosynthesis, converting the sun’s energy into food for the cell
mycoplasma
These are so small that they had to be magnified by over 18 000 to make this photo
Multicellular
This means that they are made up of two or more cells.
Unicellular
They are made up of only a single cell.
micro-organisms
Most microscopic organisms, or micro-organisms, such as mycoplasma, are examples of unicellular
pseudopods
Amoebas are common unicellular organisms that live in water. They move around using foot-like projections called pseudopods
Cilia
They are covered in hair-like structures called cilia, which move back and forth like oars to move them through the water.
Diffusion
Many substances move through the cell membrane by a process called diffusion
Osmosis
The diffusion of water is vital to the survival and health of cells. For this reason, scientists give it a special name: osmosis.
Specialized cells
This means that there are various kinds of cells, and each kind carries out a specific function or functions needed to support life.
Red blood cells
is to carry oxygen to all cells of your body. To do this, the red blood cells often must travel through extremely small blood vessels.
Marrow
Most bones of the skeletal system contain a type of connective tissue called marrow, with specialized cells that make red blood cells
hydrochloric acid
The hydrochloric acid, along with the enzymes, chemically digests proteins into smaller particles.
Mucus
The mucus helps to prevent the gastric juice from digesting the stomach itself.
Villi
small, finger-like projections. These increase the surface area of the intestine to aid in absorbing nutrients. Each villus (the singular term for villi) is covered with epithelial tissue
Microvilli
Microvilli further, increase the surface area of the small intestine to help absorb nutrients
Large intestine
By the time the food reaches the large intestine, mechanical and chemical digestion are complete.
Peristalsis
Is caused by contractions of muscle tissue that lines the esophagus. Bands of muscle tissue line the remainder of the digestive system to push the food along toward the end.
Gastric Juice
Is composed of mucus, hydrochloric acid, water, and digestive enzymes. The mucus helps to prevent the gastric juice from digesting the stomach itself.
