AOS 2.0: How do plants and animal systems function? Flashcards
What are vascular tissues?
run through the ground tissue of vascular plants, carrying water (xylem) and nutrients(phloem).
What are dermal tissues?
refers to the single layer of cells covering the outside of a plant. Dermal tissue secretes a waxy film called a cuticle (prevents unregulated water loss and protects against pathogens).
What are ground tissues?
make up the majority of the interior of the plant and carry out metabolic functions.
How to you go from cells to systems?
cells > tissues > organs > organ system > organism
What are the tree types of tissue in plants?
dermal
ground
vascular
What are the plant organs?
leaves
flowers
fruits
stems
roots
What do leaves do in a plant?
They are the site of gas exchange and are responsible for photosynthesis. In most species leaves are organised to increase sunlight exposure.
What do flowers do in a plant?
The sexual reproductive organs of flowering plants (angiosperms). Following the fertilisation of male and female gametes which are contained in pollen, seeds develop and the ovary of a flower grows into a fruit.
What is xylem?
Tubes that transport water, and minerals such as potassium, nitrogen, and phosphorus in one direction from the roots to the leaves of a plant. Composed of long, skinny tubes that run from the roots to the shoots of plants. The tubes are made from two cell types: vessel elements and tracheids.
– composed of dead cell walls strengthened by a strong supportive molecule called lignin
– located in the middle of stems
– movement of nutrients into plant occur by active transport
– movement of water into plant then occurs via osmosis
– movement of liquid up plant is driven by transpiration and capillary action (& root pressure)
What do fruits do in a plant?
Grown from a flower post fertilisation. Protect seeds and often specialised to attract animals that aid with seed dispersal.
What do stems do in a plant?
Support the leaves, flowers and fruits as well as transport water and nutrients between the roots and shoots.
What do roots do in a plant?
Absorption and storage of water and nutrients from the soil. Roots are also responsible for anchoring the plant to the ground and providing structural support.
What are the animal tissue types?
muscle tissue
nervous tissue
connective tissue
epithelial tissue
What does muscle tissue do?
contracts to exert force (move)
What does nervous tissue do?
detects stimuli and transmits electrical signals
What does connective tissue do?
connects and supports other tissues and organ structures
What does epithelial tissue do?
assists in protection, secretion and absorption
How are water and nutrients absorbed in roots?
Roots have a high SA:V ratio and there are two different pathways of water and nutrient absorption in roots:
– extracellular pathway – water (and the solutes dissolved within it) diffuses into the roots in the gaps between cells.
– cytoplasmic pathway – mineral ions (and a small amount of water) either passively diffuse into the cytoplasm or are taken up via active transport in root hair cells.
What do the body systems do?
- The nervous, hormonal and musculoskeletal systems are involved in detecting and responding to internal and external stimuli
- The cardiovascular, respiratory, digestive and excretory systems collectively function to move and exchange materials
- Other organ systems include the integumentary system (skin), the reproductive systems and the lymphatic (immune) system
How is transpiration regulated?
The fastest rates of transpiration occur on hot, dry, and windy days with bright light.
Two guard cells that surround the stomatal pore regulate the opening and closing of stomata. Stomata allow a plant to exchange gases with the environment. The main gases exchanged with the environment are CO2, O2, and H2O.
How do plants make/consume food?
Plants are autotrophs – they can produce their own food from inorganic sources
- Plants undergo photosynthesis to make organic molecules (glucose)
- Plants use cellular respiration to charge ATP from glucose
What are stomata?
Transpiration rate is regulated by stomatal pores on the underside of the leaf
Stomata close when flanking guard cells lose turgor and become flaccid
This loss of turgor is triggered by cellular signals
closed = less transpiration
open = more transpiration
What is bile and what does it do?
A bitter greenish-brown alkaline fluid which aids digestion and is secreted by the liver and stored in the gall bladder.
What does the pancreas do?
Digestive enzymes are produced in the pancreas and are released when food reaches the first part of the small intestine. The pancreas also regulates blood sugar levels and is responsible for secreting bicarbonate, which neutralises acids in chyme.
What is peristalsis?
coordinated muscular contractions and relaxations of the digestive tract wall that move food along the system
What is chyme?
A mixture of partially digested food and digestive juices that passes from the stomach to the small intestine
What are the three sections of the small intestine?
the duodenum, jejunum, and ileum
What is the hypothalamus?
A small region in the brain that helps maintain body temperature and often influences the function of the pituitary gland
What is the pituitary gland?
A pea-sized area in the brain that is often called the ‘master gland’ as it regulates many other glands, including the thyroid glands, adrenal glands, and ovaries or testes
