Multicellular Organisms pt1 Flashcards
How are cells replaced
Existing cells divide
What is mitosis
The division of the nucleus
What are stem cells
Unspecialised cells that can divide to self renew or become different types of specialised cells
What are the different types of stem cells
Embryonic stem cells and adult tissue stem cells
Embryonic stem cells are found in…
Blastocysts( very early embryos)
Adult tissue stem cells are found in….
Some organs and mucles and bone marrow
Tissues are
Cells of the same type cell that have the same job organised into groups e.g muscles
Organs are…
Several different types of tissue together
Organ systems are…
A group of organs that do a particular job e.g digestive system
Nerves carry messages through…
Nerve impulses from the sense organs to the CNS then from there to muscles or glands
Parts of the brain are….
The skull, the cerebrum, the medulla, the spinal cord and the cerebellum
Cerebrum
Concious thought, memory and reasoning
Cerebellum
Balance and muscular coordination
Medulla
Controls heart and breathing rate
What are the three different types of cells
Sensory neurons, inter neurons and motor neurons
The sensory neurons…
Carry impulses from sense organs to CNS
The inter neurons…
Carry impulses from the sensory neurons to the motor neurons
The motor neurons…
Carry eletrical impulses from the CNS to the mucles or glands
What is a synapse
A synapse occurs between neurons
What is the endocrine system
It influences almost every cell and organ. In general it controls body processes that happen slowly such as cell growth
What are the main parts of the endocrine system
Glands, organs and hormones
What transfers messages between neurons and synapses
Chemicals
Glands release what into the bloodstream
Hormones
What are hormones
Chemical messengers e.g ADH
Why can only specific tissues be affected by specific hormones?
Because target tissues have receptors for the hormones
