unit 1 Flashcards
requirements for life acronym
MRS GREN
MRS GREN
movement respiration sensitivity to stimuli growth reproduction excretion nutrition
movement
- humans are able to move; movement is brought about by muscles
- movement can consist or either a whole body or a body part.
respiration
- process by which energy is released from food
- because chemical reactions for respiration take place inside cells, it is often called cellular respiration
- cellular uses oxygen to break down glucose and turn it into carbon dioxide and water
sensitivity to stimuli
responsiveness and sensitivity go together. the body responds to outside stimuli in an appropriate way to keep the body functioning.
- responses also occur when there is a change inside the body.
- these repossess can be voluntary or involuntary
voluntary: school bell response
involuntary: seeing food and salivating
growth
growth is simply an increase in size but in most organisms the increase does NOT occur evenly.
example; human brains double in size within a year after birth.
- different rates of growth and changes that are associated with growth are known s development
- development is a gradual change in the body proportions and in organ functions
-unlike plants, animals eventually stop growing
- most growth occurs through cells dividing and producing more cells
reproduction
without reproduction, a species would die out.
- there are different forms of reproduction
- sexual
- cells dividing to multiply
excretion
chemical reactions in the body create some substances that the body is unable to use.
-excretion is the process of these substances being released from the body.
nutrition
In order for organisms to survive they require food for energy and nutrients. Energy and nutrients are essential for growth, survival and reproduction. Many living things, such as animals, acquire nutrients by eating other organisms.
body organisation
-the human body is complex asf
-it consists of many levels of cells, tissues, organs and organ systems.
each level combines together to make the next level.
body organisation def.
cells- building blocks of all living things
tissues- a group of similar cells that preform the same function
organs- groups of different tissues with a specific function
organ systems- groups of organs that work together to preform a specific job.
examples of organ systems
cell. - red blood
tissues- epidermis/epithelial
organs - heart
organ systems- respiratory and circulatory
types of tissues
connective- found in between all other tissues
epithelial- layers of surfaces cells that cover the surfaces of body which they contact
muscular- soft tissue that composes muscles
-skeletal
-cardiac
-smooth
nervous- groups of organised tissues and cells within the nervous system
how many types of cells are there
about 200
animals cells
all living things things are made up of cells
