Biology Unit 3 Flashcards
Define: Anaphase
the phase in mitosis where chomosomes split into two halves and move to opposite poles of the cell
Define: Apoptosis
the controlled death of a cell that is no longer useful
Define: Cancer Cell
a cell that has somehow been damaged so it reproduces uncontrollably
Define: Cell Cycle
a cycle of growth and cellular divison that allows for the growth and reproduction of cells
Define: Cell Membrane
a layer of double lipids that protect the cell and allow different substances to passs through it (part of the cell)
Define: Cell Specialization
refers to the fact that different types of cells have different structures and abilities to perform their function efficiently
Define: Cell Wall
a part of a plant cell that is the rigid fram arounf the cell that provides strength, support and protection
Define: Centriole
forms the poles of the cell during mitosis and it allows for mitosis to occur. There are no centrioles in plant cells
Define: Chloroplasts
an organelle that contains chlorophyll which allows for the cell to carry out photosynthesis. They are only found in plant cells.
Define: Chromosome
the shortened chromatin that duplicate to form sister chromatids
Define: Cytokines
the process of mitosis where the cytoplasm and everything in the cell are evenly divided.
Define: Cytoplasm
the jelly-like substance that supports all organelles in the cell
Define: Cytoskeleton
the internal network of fibres that help maintain the structure of the cell
Define: Differentiation
the process through which stem cells become specialized
Define: Golgi Apparatus
an organelle that recieves protein from the endoplasmic reticulum. It is to modify, sort and package proteins
Define: Interphase
the phase of mitosis where the cell grows and prepares for cell divison by duplicating its genetic material
Define: Metaphase
the phase in mitosis where the double stranded chromosomes line up in the middle of the cell and spindle fibers attach to the chromosomes
Define: Mitochondria
an organelle that converts chemical energy in sugar into energy that the cell can use. It supplies the cell with energy
Define: Mitosis
stage of the cell cycle in which the cell divides into 2 new daughter cells
Define: Nucleus
an organelle that controls all activities of the cell
Define: Organelle
a part inside a cell that performs a certain task to keep the cell functioning
Define: Prophase
a phase in mitosis where chromosomes shorten ad thicken and the nuclear membrane dissolves
Define: Sister Chromatids
the pair of chromosomes that have duplicated and therefore are identical
Define: Stem Cell
an unspecialized cell that can form specialized cells
Define: Telophase
the phase in mitosis where the chromosomes reach the poles and the chromosomes unwind and the nuclear membrane reforms
Define: Tissue
groups of cells that function together to perform a specialized task
Define: Vacuoles
membrane-boundorganelles that store nutrients, wastes and other substances used by the cell
Define: Capillaries
very small vessels (one cell thick) where gas exchange occurs
Define: Circulatory System
the system that allows blood to deliver oxygen and nutrients to the cells and take waste away from the cells
Define: Digestive System
the system that allows for ingestion, digestion, absorption of nutrients and elimination of solid wastes
Define: Excretory System
the system that eliminates wastes. Consists of the skin, kidney, bladder, ureter and urethra
Define: Esophagus
the tube that connects the mouth to the stomach
Define: Heart
a very strong muscle that pumps blood throughout the entire body
Define: Homeostasis
the tendency of an organism to maintain a steady state; an acceptable range of physcial and chemical conditions in which body cells, tissues and organs can operate efficiently
Define: Integumentary System
the system that covers and protects the body and the glands help control body temperature
Define: Interdependant
refers to one system relying on other systems to function efficiently
Define: Intestines
there are 2 parts: the small intestine digests and absorbs food, the large intestine absorbs water and stores waste
Define: Lungs
the organ that takes in oxygen to be used by the body and sends out carbon dioxide
Define: Organ
a group of tissues that work together to perform a certain task
Define: Respiratory System
the system that takes in oxygen and allows it to be used by the body and also gets rid of carbon dioxide
Define: Skin
the protective layer of your body and allows for moisture to escape the body
Define: Stomach
an organ in the digestive system that breaks down food with muscles and stomach acids
Define: Lysosomes
small organelles filled with enzymes that break down invading bacteria and damaged organelles
What are the 12 main organelles?
- cytoplasm
- cell membrane
- nucleus
- vacuoles
- vesicles
- mitochondria
- lysosomes
- golgi apparatus
- endoplasmic reticulum
- cytoskeleton
- cell wall
- chloroplasts
What are the 4 stages of the cell cycle?
- G1 (growth
- S (synthesis or replicating DNA)
- G2 (growth and interohase begins)
- Mitosis
After interphase, what are the rest of the phases of mitosis?
Prophase Metaphase Anaphase Telophase Cytokinesis (to remember: I Prefer Mice And Talking Cats)
Define: Centromere
the point on a chromosome by which it is attached to a spindle fiber during mitosis
Define: Chromatin
the stringy strands of DNA before they form chromosomes
What are the 4 types of tissue?
- Epithelial Tissue
- Connective Tissue
- Muscle Tissue
- Nervous Tissue
What is Epithelial Tissue?
cells that are tightly packed to form a barrier. The barrier can be 1 cell thick or several layers thick. Ex. skin, glands, lining of organs
What is Connective Tissue?
it joins tissues together and also forms blood as well as provides structure and support. Ex. ligaments, bones, blood
What is Muscle Tissue?
it allows for movement. You have voluntary muscles that only work when you want them to (ex. skeletal muscles like biceps). You also have involuntary muscles that work all the time without you controlling them. Ex. smooth muscles (stomach), cardiac muscles (the heart) and the brain
What is nervous tissue?
it transmits and stores information as well as respond to stimuli. Ex. brain cells, motor neurons
Summarize the job of the Skin.
-it has 2 layers- the first one is the epidermis which is the outer protective layer and it makes vitaminD. The second layer is the dermis which is made of connective, nervous and muscle tissue. It is the inner layer and it secrets sweat, insulates and contains nerves. The skins function is to protect from damage, disease and dehydration, it regulates body temperature and it excretes wastes
Summarize the Lungs.
They are made of connective and epithelial tissues and the lungs contain bronchus and bronchial tubes that lead to tiny air sacs called alveoli (a thin layer of epithelial tissue containing blood vessels). The lungs function is to carry out gas exchange and absorb oxygen into the blood and remove carbon dioxide from the blood
Summarize the Heart
It is a 4 chambered muscular pump that is connected to major blood vessels. Its function is to pump oxygenated blood to the entire body and pumps deoxygenated blood back to the lungs to become oxygenated
Summarize the function of the Stomach
It is made up of all 4 types of tissues and is a muscular sac containing digestive juices and enzymes. Its function is to break down food through muscular action and chemical digestion.
What are the 2 types of stem cells?
- Embryonic Stem Cells
2. Adult Stem Cells
Define: Embryonic Stem Cells
they are found in embryos and are able to undergo differentiation and can differentiate into other cell types
Define: Adult Stem Cells
are highly specialized and are embryonic stem cells that have divided and become more specialized. Most of these cells are invloved in the replacement of damaged tissue and can regenerate from the cell of one organ into the cell of a different organ
Why are Stem Cells important?
because some cells go through mitossi faster than others, so if we can use stem cells, we can replace damaged cells to help repair a damaged body faster
What are the main parts of the circulatory system?
- The heart- a very strong muscle that pumps blood throughout the entire human body
- Arteries- carry oxygenated blood away from the heart
- Veins- carry deoxygenated blood towards the heart
- Capillaries- very small vessels (1 cells thick) where gas exchange occurs
What happens in the Respiratory system?
2 things happen- breathing and gas exchange
- when you breathe in, your diaphragm contracts and lowers, your rib cage elevates causing air to be sucked into the lungs
- when you breathe out, your diaphragm relaxes and rises and your rib cage depresses causing air to be forced out of the lung
- gas exchange occurs in the alveoli where oxygen coming into the lung is traded with carbon dioxide from the body
- an enzyme called hemoglobin in red blood cells carries gases in the body
What are the 4 functions of the digestive system?
- ingestion (taking in food)
- Digestion (breaking down food)
- absorption (absorbing nutrients into the blood stream)
- Egestion (eliminating wastes)
What happens in ingestion?
food is passed from the mouth to the stomach through the esophagus. The esophagus does this by rhythmic muscle contractions called peristalsis
What happens in digestion?
food is broken down physically by chewing in the mouth and it is broken down chemically in the mouth (with saliva), stomach (with stomach acid), and small intestine (by digestive juices released by the pancreas and gall bladder)
What happens in absorption?
nutrients are absorbed into the blood stream through the walls of the small intestine. Water is absorbed through the large intestine
What happens in egestion?
the waste (mostly fiber) is expelled from the rectum and anus
What is the function of the brain?
to control body functions and coordinate responses and activities
What is the function of the lungs?
bring oxygen into the body and gets rid of carbon dioxide
What is the function of the skin?
to cover and protect the body
What is the function of the kidneys?
remove waste from the blood and regulate water fluid levels
What is the function of the liver?
to make bile and remove toxic substances from the body
What are cancer cells?
Cancer cells are cells that have somehow become damaged and reproduce uncontrollably. The cancer cells can reproduce until they reach the blood stream where they can travel all over the body. Cancer cells are often smaller than normal cells.
